The swr led board is actually the Tayloe SWR circuit (Google it) and the actual caps\inductors circuit I have seen on the net before. So it works. The video was a classic of why we're called "amateurs". Kudos to John for not bad-mouthing the kit due to his errors. All I can say is the parts alone are worth the $12 the kit costs when you add shipping to your parts order (unless you have a parts house close by). Thanks John for the video and giving it to us with the bark on the branch. See you at the Jackson hamfest I hope.
Best darn video I've seen in a long time, friend. Subscribed. Next month, when I pass both General and Extra, I'm going to use this tuner to work 80 meters on my QRP rig.
Hello Anthony welcome to the wonderful world of amateur radio. As a new ham you may find my channel interesting, I've been doing a similar sort of thing to John for the last few weeks, a few technical bits and pieces that those entering the hobby may find useful or interesting.
Bought this kit as well, emailed the seller for the "instructions", they sent me a Word document, (similar to yours but less Chinese) and the "Chinglish" is pretty confusing! I really appreciate your videos, have watched a lot of them and they are really helpful! Thanks very much and keep them coming!
For those who don't know, these tuners have other uses besides matching low-powered transmitters to their antennas. Since the tuners are rated 1-30mhz, it means they are continuous coverage of the LF and HF bands and make great matching networks for shortwave receiver antennas. Shortwave listeners often have to get by with just a random wire or length of something conductive simply because no resonant antenna can possible cover all the billion SW frequencies. But! a little LC matching network like this can match a random wire antenna to the receiver and cause a huge difference in signal strength as well as reduce off-frequency/out-of-band interference signals. Electronic "active" antenna tuners don't work any better in my opinion and often cause a lot of their own internal noise. If these little tuners catch on, someone with skill and know-how will eventually write an assemble document in language everyone can understand, making the inexpensive kit a very attractive option.
Thanks for this,my kit came with no instructions,and your little vid has made all the difference,let's see if I can get this to work.all the best 73's Tony 2E0FTQ
Just finished my build, and the tuning knobs modification just didn't work for me. I ended up using my own from the parts box, which is fine. The variable inductor wasn't too bad at all to wind and assemble onto the rotary switch, but yeah not for beginners. I tested mine using an MFJ analyzer and dummy load and yeah the thing rocks! Very pleased
you can get a SWR meter kit (the sort that stays in line permanently up to 100W) from Diz at kits and pars in FL for $12 USD. Now if you can find a cheap milliampmeter to go with this - preferably edge type. you have SWR and Tuner all in one box for say USD $18 odd postage on the Diz kit and $20 here which is close to $38 plus a LOT of time. These micro kits that don't use proper Alum plate capacitors are only good for 10 W or so. If you can find some nice 365 PF air gap capacitors and and put it in a decent box (such capacitors are around USD $10 ea from PRC) .. you now have a fifty watt level tuner. if the capacitors have no sharp edges and you change to a larger toroid in type-06 material you have a 100 W capable tuner. TE Fidler NzL If you want to put it in a metal box you do need a bit of 12mm PE chopping board as a spacer to keep the toroid off the metal because all toroids leak a little and at RF the losses to the enclosure can be considerable if the toroid is clamped to Alum or Steel. the securing of the toroid is best done with a nylon screw and nut or with three cable ties.
Great video build John, thanks for doing this one. I have been thinking of getting this one for a go box with my R4030 QRP radio... 73 Jimmy, ARRL TS, WX9DX
Just got my kit. Since I'm not using it for transmit I can omit the entire circuit board and switch and just build the T match. Thanks for the tips on winding the inductor too! 73 DE N2NLQ
I soldered a moving-coil meter (100 microampere full scale) in series with a 10 kOhm resistor and put this combination parallel to the LED. Now the point of best adjustment can be found with much more accuracy than with the LED alone.
Hi K7AGE, Just received my 'Days' antenna tuner here in England. It took 5 weeks to be delivered from China but only cost £8.50. I have printed off the schematic and wondered after winding the main toroid, what is the connection sequence for the 12 taps to the main capicitor?. I have never made anything like this, but don't feel too daunted as your 'you tube' video is very informative. Have you found the LED SWR light to be very effective. I did not realise that this is an SWR warning light and should dim when the SWR is good. Thanks for posting both videos. Paul M6MIY Ipswich England.
Thanks John, excellent informational video. The word you were looking for is "Chinglish". In all honesty, if this kit just fit a bit better together and the instructions were in proper English, there's no real reason why this couldn't be a first timers kit. I think the bigger issue is really the instructions. All it needs is for one of the Chinese manufacturers to pay a Ham $100 for a couple of hours work tidying it up. As you say, the pictures are great. Some of it reminds me of my VHF/UHF Quansheng handy.
nice work john I've built several of these chinese kits including the QRP Pixie for $5! Needed to replace the crystal in that one however. Thanks and 73s
Winding the toroid in this manner is difficult. I used 0.8mm (AWG 21) enameled copper wire which can be soldered on the outside of the toroid. Then short wires connect to the 12 position rotary switch. A very hot soldering iron is required to melt the enamel.
Great video John!! I wish more people would explain building things like you do. I just emailed you about the schematic. I am thinking of getting one of these. I just got into the QRP bug and just finished building my second Pixie 40 Meter QRP rig. The first one I blew the final, thought I had my 80 Meter dipole tuned with my MFJ 969 tuner using my Vectronics analyzer hooked to it to get the SWR down. Apparently I didn't!! I am building a specific 40 Meter dipole, but would like to have a QRP tuner and have been looking at this one. Again appreciate your videos and enjoy how you explain things. 73 DE Juddie WD8WV
W5CYF / TinkerJohn I enjoy watching them quite a bit! I like the idea of being able to make your own equipment. I got the kit yesterday and finish d it up tonight. I hate to say it but what a piece of junk! Put the knob on the inductor messed up the inductor. It no longer clicks, if free spins from A to about F, then clicks to G and I and then free spins to L. I had no problems winding the inductor or the other little one. I was really hoping for a little bit better quality, but as a good friend tells me you get what you pay for. But heck the Pixie works better than the tuner!
Got mine together --- working fine, except for the LED which I can't figure. Certain older tuners used decades ago had a bulb which indicated resonance and allowed their use without a meter; especially with the vacuum tube RF finals which were the standard then. But, best I can judge from the pidgin English instructions, this LED is supposed to go OUT when resonance is reached. In any case, my LED has never illuminated under any condition of (non)resonance (and before some says it ---yes, the LED polarity is correct ---- anode to positive +). Another construction note is about the tuning capacitors. In the first photo of the manufacturer's partially-translated instructions, the unwired components are displayed with the capacitor terminals pointed down. In the subsequent photo of the wired version, the capacitors have been rotated 180-degrees so that the terminals are pointed upward. Anyone building the kit needs to watch out for this, otherwise they will be un-doing then re-doing their work. Of course the terminals could be left in the unwired configuration and the hookups reversed, but since building this thing relies on copying the photos I don't advise it. I think reversing the leads has no effect anyway, depending on whether the capacitance of the outside leads-to-ground is identical; some of thse little phenolic caps are symmetrical; some ain't. Never did figure the mechanical tuning knobs out, but lo' and behold I found two extension shafts in the parts box which are made for the espress purpose of extendng the flush shafts of these little "transistor tuning capacitors." So, I'm smokin' in the tuning department. Last, I should say something good about the kit - other than it does work. That something is the case. Undrilled and unmarked or not, the case is the most superb kit case I have ever laid eyes on! The thing is hard, thick and I don't think anything less than a home run baseball bat swing could crack or chip it. It reminds me of the old Bakelite technology minus the brittleness (you can't chip this thing!), but of course it's not. And, the waterproof claim is real too --- there's even a waterproof gasket to which fits into a recessed groove where the case and its back meets. Of course the holes you drill won't be waterproof, and in any case I haven't heard of Scuba QRP'ing yet. But, I wish all my other projects had cases one-fourth the substance of this one! P.S - The claimed specs for this toy is 5-watts max for the dummy load, but I never could figure what the max tuner wattage is. Ever figure that one out? It looks like it should handle 10w at a 100% duty cycle, and maybe 5 more watts for a CW cycle. I noticed as I built it that if heavier wire had been used on the main toroid (there is room on the form) and the phenolic caps swapped out for some real air variables, this thing could easilty handle 40-50 watts without getting to hot.
Great video. Just looked you up on QRZ and just about fell out of my chair. Did not know you were in Whitehouse! I live over in Jacksonville, and am the current secretary for the Cherokee County Amateur Radio Club. Small world I guess. Thanks again for the videos and maybe I'll catch on one of the local repeaters. 73 K5WCF
William, Glad to have you following along and thanks for watching my videos. I work mostly CW on 20/40 meters (no room for 80 meter antenna). Perhaps I'll get a chance to meet you in person someday. ~John
Enjoyed the videos, and you should patent that toroid-bobbin method, lol. If it's tricky for a 'ham' then I wonder if I'll ruin it - I have a soldering iron, but the drilling... I have 2-6mm only, looked on ebay - can't find a tools list. Ah well... great videos anyway :)
John, this is my second time to watch your video. My Chinese tuner came in and after opening up the box, it was worse than I thought. The toroids aren't the problem with me - it is the variable caps. Each cap has 3 terminals and 2 sections. One section is about 150pF & other is 50pF, That adds up the 200pF if used in parallel. I was expecting at least 400pF. Oh well. Anyway yours tuned and so will mine, I hope, Speaking of hope - I hope to work you QRP.
David,Hopefully you'll be able to complete your tuner...the instructions are not very clear on several things. Hope to meet you soon....CW of course!John
I just looked ZM-2 ATU and it seems that they are similar designs, so looking the photos of the other and the instructions, it will probably help build this one.
Few years have passed by John and I hope your well? I'm afraid nothing has changed regarding this kit. Same difficult instructions, same monstrous switches, (I've built a K2 and some Rockmites, but this beats all)! Without your help on this video, I think I would have just given up!! 73s
It appears that they have altered the PCB board slightly as the 51ohm resistors now fit the board, but still found two errors: 1st - the FT 37-43 5 turn/2 turn toroid is incorrectly marked on the PCB but correct on the schematic. (The 5 turns should connect to the Diode trace and ground.) 2nd - the T106-2 large toroid appears to be "upside down" on the schematic. The 10 turns should be the last connection on the switch and the beginning of the 1 turn should be connected to the two variable capacitors. Without this, the 10 turns keep the tuner from minimizing SWR on 14 mhz and higher. The schematic isn't clear on the variable capacitor wiring either. They have 3 legs. The 2 legs on either side need to connect together. This increases the total range of capacitance. I use a 50 ohm dummy load connected to OUT and tune to it to start. Then replace the dummy load with the antenna and finish tuning. It does actually work (with my end fed antenna). Be sure to flip the toggle switch to bypass the SWR meter for normal operation.
I actually bought mine from a Canadian source and he had included the schematic. The SWR bridge most closely resembles that of the KD1JV circuit, which I think would be a good source of info, and available from the ALT tuner in the archives of Hendricks QRP. I don't understand where they came up with their tap info, as I would make it a little more linear and tap it at: :2, 4, 6, 8, 10, 13, 16, 20, 24, 28, 34, 40 as in the VA3IUL tuner. We'll see if mine works. Lee, WA8QFE
I don't know if you figured out but a yl ham on TH-cam pointed out that the diagram was wrong the 10 turn part is position 12 and the first one turn portion hooks to the tuner caps and the swr transformer Labels on the circuit is backwards I believe 2 on the in a different 5 on the out.
M1KTA said he has 2 kits and one board is correct. The board with the error in the cap, you could solder on the back of the board.Just make sure you are not putting it across the secondary winding of the transformer. Lee, WA8QFE
Nice video John, Some of these tuner kits are prizes at the Lobstercon QRP Camping and Hamfest in Maine next week and your instructional videos will be sent along with the kits to the prize winners. Thanks, Jim / W1FMR
Great video. Built One Myself Did You Have Trouble Getting SRW circuit Working Properly? Im Getting This Problem With My Circuit Never Got Around To investigating It
I was curious, I notice here we start with ten turns, and then add the other winding's to this with the knob adjustment to gradually add more turns make our loading coil larger. Wouldn't adding a switch and connecting one side of it to the far end of the coil (and thereby using the coil in reverse) extend the range? Where fewer turns are used first, and the ten turn section is added last? I just noticed the last of the coil is electrically free, and this gave me a thought on adding a second range in this way.
Hi, thanks a lot for these very useful videos. I also purchased the same kit, however I have troubles to follow the schematics provided. In particular the varicaptors have three legs (O-G-A) and I am not sure how to connect them, or from where to where? would you have some more detailed circuit diagram? Thanks a lot!
+perdidoanonimo If you are still interested, I noticed from some of the pictures in the "instructions" that the O and A terminals are jumpered together. Then one lead goes to the G terminal, and the other lead goes to the jumpered O and A. At least that is the way I built mine. But I haven't tested it yet.
I just put one of these together today. I haven't tested it yet. Be carefull when putting the screws into the variable capacitors. I had to put washers on mine because the screws were too long.
W5CYF / TinkerJohn I haven't tested it yet. I need to get some more BNC cables first and I'm planning on moving some things around. I'm using a Genesis G11 SDR radio and I need to change computers and set everything up again. It'll probably be a while before I'm all set up and running again.
I'm building this eBay beast too. Anyone considering reducing their net worth by $20 to acquire this Chi-Com people's product should realize that there are no assembly instructions. No manual of any kind comes with the tuner, and the on-line manual is completely undecipherable. It's apparent that the original Chinese text was run through one of those free online Chinese-to-Whatever language translators. Putting this thing together means that you will have only some photographs and a rather poorly annotated schematic. You really need to know how LC tuner circuits work to succeed at this one. Unless you can look at a part and already know its function and where it fits in a tuner circuit, I don't think you'll be able to handle this one. And, the parts in the kit are different than those shown in the photos. Watch the too-long mounting screws on the tuning caps. They are flat-headed, but if you countersink them as that design intends the mounting screws will over-penetrate the caps and damage the rotor/stator. The inductor switch leads are too large for the board, so the board will have to be drilled out larger, and like you say the spacing for the 1-watt resistors is too narrow --- but you cannot stand them upright because the board wouldn't fit into the case. The saving grace of this kit is two-fold, (1) it's cheap, and (2) it's a simple kit with only a few parts. Oh! And on those tuning knobs. I have never in my life seen a tuning knob with hardware on the inside of the knob. I've tried every way I could think of to get the knobs on the shafts, but it ain't happening, The knobs are flush with the mounting panel, and the only solution I can think of are those extension shafts which are made just for the purpose of making the shaft's longer so a knob can be fitted. Anyway, good review ---- I was hoping you'd get around to solve the mystery of the RoboKnobs! :)
Maybe I'm just incredibly thick, but I'm already stuck on the assembly. 1) the photograph of the wound toroid in the build manual - which they tell me to copy - has a couple extra turns after the final -2-2-2 sequence, and no twisted final -1 tap, with a total of 11 twisted taps and two loose wire ends. That doesn't correspond to the 10-2-3-2-3-3-2-4-2-2-2-1 sequence in the schematic. 2) I don't understand how I'm supposed to orient the switch relative to the taps with only 11 taps-- what do I solder to switch pos 1? The 10 tap, I assume? Maybe I should just ignore the photo in the docs and follow the schematic. This kit build isn't my first rodeo by any measure, but it feels that way.
Great vid. I noticed that the switch pin-outs aren't explained in regards to which witch tap they go to on the main toroid. My instructions don't include this detail either. Ant clues?Cheers. ;)
You have a lot more patience than I, that's for sure. The instructions sound bloody funny, good job they included the pictures, as they say 'a picture tells a thousand words'. It would have been good to see the inductor and switch with all of the taps soldered on prior to installation in the box, I can imagine that would have been a nightmare. Still, as you say for $20 you can't really go wrong. You couldn't buy all of those components for $20 down at the local electronics shop. How much power do they say you can put through it? Have you used it on the air?
VK6CS Thanks for taking time to comment. Yes, the tuner works (kind of), there is an error on the PC board and I'll be making an update video in a month or so to show the correct circuit. ~John
Must be warmer in the radio shack then the machine shop today. :D Looks like the original box would have been a very tight fit for final assembly anyway. Half what I get from China has no instructions at all so you were ahead of the game on this project. Any reason to make computer generated dial faces just for reference settings? Another fun video John.
Yep...getting a little cold in the garage so I moved inside for a spell. I will be making a dial face on computer but right now it's just a few labels from a cheap label maker. Take care, John
Lots of Sources for this unit. Not one with the schematic. Picked this up at a flea market but he did nit have the manual. Still looking. The parent company is all in Chinese.
John thanks for the great video as usual, can you supply a link to the build instructions website as I cannot find the link and I have asked the vendors and they are not too helpful in this respect cheers paul
Great videos and tips, just one question with this tuner, 1 tail I can see where it goes but the other one is a mystery to me, so does it go to the centre pin on the switch along with one of the yellow tails? thanks for any advice. 73's
Just curious as to what settings you have found on the center dial that correspond to the different ham bands. I ordered one of these and am waiting for the delivery. I will be using your video to assist in building it as the directions are pretty garbled from the poor translation.
Joseph,I usually find the middle range fits most antennas. Your situation may be different, but that was a good place for me to start. Good luck with your build.~John
I've brought this kit but I have come across a issue, please need your advice.. Regarding the windings where do the copper wires get soldered, from the PDF instructions one end is soldered to one tuning side but not sure where the other gets soldered, schematic doesn't show nor the photos with instructions... Many thanks and 73's M6EVD
Thanks for watching. I don't have the tuner any longer, but as I recall one end is soldered to ground and the other to the variable capacitor. Hope this helps. ~John
Thanks for a nice video! Have you tested your kit on all bands 80m to 10m? I assembled my kit this week and it could not match wire antennas other than on 80m, maybe 40m. The reason: inductor seems to be "upside down"! It should not have upper 10-turn section connected to variable capacitors! The inductor should probably be reversed so that 1-turn end goes to capacitors and 10-turn end to ground - so all connections to rotary switch should go opposite way! Otherwise you have always 10 turns even at minimum setting and you can not match various antennas at higher frequencies, say 14...21...18 MHz! As I noticed this afterwards, I had to remove turns from my assembled tuner, I reduced top section of the inductor from 10 to 1 turn and now it works quite well. The tuning became much sharper when I also connected bottom of the inductor to ground as normally done in T-matching circuit!
YouSepeteus Thanks for watching and for you comments. As you noticed there are some errors in the instructions that I found after the video. The wires were reversed and the PC board has an error. The schematic is correct and if built to that the tuner works fine. 73/John
+W5CYF / TinkerJohn So I'm confused - where do I connect which end of the inductor wire? The only other error I think I found in the PCB was that the # of turns on the little inductor was reversed from the schematic.
Hi john, thanks for making the video. I've now subscribed to your channel.I have a question for you, or anyone reading that might know.Looking at the schematic, I can see that the free end of the toroidal (at the 10 tap end), goes to the bridge between the two variable caps and that the centre connector of the multi rotor switch goes to ground. However, the schematic doesn't show where the other loose end of the toroid winding goes. Do I ground it? Or is it left open?Thanks in advance for your help !!
It is left open, connected to nothing. the device begins with the ten turns end and the rotatory switch adds more turns to increase the inductance as you rotate the grounded wiper arm around the selector switch. The turns beyond the wiper arm are not in use.
John this is going to seem a silly question to you but when winding the main torroid the begining of the wire attaches to the variable capacitor on the left but when you've finished your windings ,where does the end of the wire go please Have been pulling my hair out for days now so your help would sure be appreciated.
Although i no longer have the tuner and can only go by what I recall, I believe the coil winding went from the variable cap to ground. The schematic is correct and will be helpful. Hope this recollection helps. 73 ~John
Thanks again John - one question - how do you adjust this if you don't already have an antenna analyzer? I'm looking for QRP portable and minimum weight (EFHW most likely) and so want to bring as little along as possible.
Kevin, Thanks for watching and for your comment. You don't need an analyzer, all you do is first tune for loudest noise level by listening to radio and first tuning the middle switch, then tune the two capacitors on each side. Then key down (briefly) and then fine tune until LED goes out. It has a very fine tuning range, but once you use it a little, it becomes easy. 73/John
W5CYF / TinkerJohn Thanks for the super fast response! I'm going to order this, seems like it's only U.S. competition is phenomenally slow to ship, I can save $10 and get it just as fast. (If he shipped expeditiously, I'd pay the extra money)
Thanks for the Video John. Can you recommend a tuner kit for someone like me. I've never made a tuner from a kit but I do know how to solder. I'm knew to the ham...just passed my technician exam.
Armando, thanks for watching and congratulations on passing your tech exam. Welcome to ham radio. There are several kits available. Depending on if you will be operating portable or home; qrp or full power, vhf or uf will all make a difference as to what type of kit you need. Suggest looking at 4 states QRP, MFJ and even search Amazon. Hope this helps. ~John
Hello John, I was wondering if you were able to get the LED circuit to work in order to tune antennas? The reason I ask is because I don't have an antenna analyzer to use (I've heard that the pcb may have an error). Also, one end of the toroid magnetic wire goes to ground, did you solder that ground to the center of the switch (there's a input on the center of the selector switch). Just a Technician here- KG7ODK. Thanks.
Evan Wolfe Evan, Thanks for watching and for your comments. There is an error on the PC board, the schematic is correct. Just follow that and you'll be fine. ~John
W5CYF / TinkerJohn Could you just indicate where the error is on the board, just so we can watch out for it/check it against the schematic, before we start - I have one of these kits on the way £11/$16.
hello john, my variable capacitors are out of use, i need replacement the capacitors. What is the value of capacitors? Can i use metal variable capacitors? Thank you ! Bye
John, I'm trying to figure out how to solder those tabs from the toroid. The switch has 12 connection points plus one in the center. The toroid has only 11 tabs. Thank you.
Adrain, Hopefully I'm not to late in replying. There are several different designs of the tuner. Yours will have one tab not connected. It should not affect operation ~John
The switch changes over to the swr led circuit. It does not bypass the tuner. The circuit contains a dummy load circuit that it uses as a reference to the antenna. When the impedance of the antenna with tuner matches the dummy load, the LED goes out. I wouldn't put much power through that circuit.
Thanks for watching. The knobs are a lot of trouble so i just glued extensions to the caps and put the knobs on that. I no longer have the tuner, otherwise I'd send pics. Hope this helps. ~John
Ever thought of making some decent step by step instructions in writing with photos (like you can find for Pixies) and sell them for download online for $.50 - $1. At 50,000 views I imagine you would get quite a few takers. I personally would be glad to buy some decent instructions I can read as I go rather than constantly viewing portions of a video.
Peppzz Sorry for the delay in getting back to you, just now getting a chance to do some catch up. The switch should have 12 (or 10) positions. Hope this helps. ~John
Thanks for the comment. You are correct, the Chinese instructions make the kit much more difficult that it needs to be. If one can follow schematics the kit was not that difficult. ~John
Ok, this "kit" is totally goofed. Not only do the photographs show the thing wired backwards, but the PC board has production errors... the reason I couldn't get the out-of-resonance light to come on. FIxing this required cutting traces on PC board and running jumpers to the correct components. The thing is finally running as advertised.
W5CYF / TinkerJohn No problem, John ---- didn't mean to hijack your thread, but I know of no other forum currently discussing this kit. On yours - if you haven't already done it - reverse the wires on the IN and OUT connections using the final assembled photograph as the guide. And the 104 ceramic capacitor is connected to the 5-turn side of the smaller toroid, which is incorrect. Cut the trace linking the capacitor to the 5-turn winding, then reroute that 5-turn wire to the anode side of the 1N60 diode --- just as the schematic shows. You can see that the board is built with errors, but the schematic is correct. I noticed right away that with the way the board was traced, the 104 capacitor was passing all RF energy directly to ground; neither the 1N60 rectifier or the red illumination LED were seeing a speck of it. Once you do this, your red light even works!, although it's an odd function. Apparently the additional SWR circuitry allows you to tickle the tuner with reduced power until you get the thing tune, thereby reducing the risk of damaging your RF final amp. Throw the switch to the left which activates the dummy loaded SWR indicator circuit, and just use a watt or two. Adjust the tuner until the red light goes OUT, then you have minimum standing waves --- your transmitter and antenna are matched. Then, just throw the switch to the right (operating mode) and apply full power which I expect is no more than 15-watts continuous, or maybe 20-watts at 50% duty cycle. I used the tuner in CW mode with a homemade linear amplifier running 22-watts and detected no damage or even appreciable heating. Just remember that the SWR tuneup circuit is only designed to take a couple of watts. And the little tuner performs exactly as advertised ---- it WILL tune a random antenna in the 1-30 mhz range. I used a lab generator and running max inductance the thing will tune well into the AM commercial broadcast range.
I admire your honesty and perseverance, John.
73
The swr led board is actually the Tayloe SWR circuit (Google it) and the actual caps\inductors circuit I have seen on the net before. So it works. The video was a classic of why we're called "amateurs". Kudos to John for not bad-mouthing the kit due to his errors. All I can say is the parts alone are worth the $12 the kit costs when you add shipping to your parts order (unless you have a parts house close by). Thanks John for the video and giving it to us with the bark on the branch. See you at the Jackson hamfest I hope.
+BigDawg Poochman
Thanks for watching and for your comments. I do plan on attending the Jackson hamfest...hope to see you there. ~John
Glad to see you back on youtube.
Thanks for your comment and for following along.
John
Best darn video I've seen in a long time, friend. Subscribed.
Next month, when I pass both General and Extra, I'm going to use this tuner to work 80 meters on my QRP rig.
Thanks for watching and for your comments. Good luck on your exams and welcome to the world of HF. ~John
Well done on another great video! Thanks for sharing your knowledge
Hi John: thanks for the video. I learned something about winding toroids. Thanks for the tip about winding the wire on a spool first, very helpful.
Thanks for watching. ~John
Great video! As a new ham I rely on these types of video's to learn the basics of the the radio art.
Anthony,
Thanks for your kind words and for watching my videos.
John
Hello Anthony welcome to the wonderful world of amateur radio. As a new ham you may find my channel interesting, I've been doing a similar sort of thing to John for the last few weeks, a few technical bits and pieces that those entering the hobby may find useful or interesting.
Bought this kit as well, emailed the seller for the "instructions", they sent me a Word document, (similar to yours but less Chinese) and the "Chinglish" is pretty confusing! I really appreciate your videos, have watched a lot of them and they are really helpful! Thanks very much and keep them coming!
Can u infom me their email address as I like to get one KIT? My email address is bsnvu2yc73s@gmail.com
Very helpful. I'm just about to build mine and will be referring back for reference. Good stuff John.
Thanks for watching, the turner works well. ~John
For those who don't know, these tuners have other uses besides matching low-powered transmitters to their antennas. Since the tuners are rated 1-30mhz, it means they are continuous coverage of the LF and HF bands and make great matching networks for shortwave receiver antennas. Shortwave listeners often have to get by with just a random wire or length of something conductive simply because no resonant antenna can possible cover all the billion SW frequencies. But! a little LC matching network like this can match a random wire antenna to the receiver and cause a huge difference in signal strength as well as reduce off-frequency/out-of-band interference signals. Electronic "active" antenna tuners don't work any better in my opinion and often cause a lot of their own internal noise.
If these little tuners catch on, someone with skill and know-how will eventually write an assemble document in language everyone can understand, making the inexpensive kit a very attractive option.
Thank John, Excellent tutorial cheers...
Got one of these kits coming on a slow boat from China for $11.37 shipped. Good tip on the coil winding and tap method! :) 73 -Mike
Thanks for this,my kit came with no instructions,and your little vid has made all the difference,let's see if I can get this to work.all the best 73's Tony 2E0FTQ
+tony street
Tony, thanks for watching and for your comments. ~John
Thanks for the video. My kit has arrived and will try to build it one on these days.
Thanks for watching and for your comment. Good luck with your tuner. ~John
Just finished my build, and the tuning knobs modification just didn't work for me. I ended up using my own from the parts box, which is fine.
The variable inductor wasn't too bad at all to wind and assemble onto the rotary switch, but yeah not for beginners.
I tested mine using an MFJ analyzer and dummy load and yeah the thing rocks!
Very pleased
you can get a SWR meter kit (the sort that stays in line permanently up to 100W) from Diz at kits and pars in FL for $12 USD. Now if you can find a cheap milliampmeter to go with this - preferably edge type. you have SWR and Tuner all in one box for say USD $18 odd postage on the Diz kit and $20 here which is close to $38 plus a LOT of time. These micro kits that don't use proper Alum plate capacitors are only good for 10 W or so. If you can find some nice 365 PF air gap capacitors and and put it in a decent box (such capacitors are around USD $10 ea from PRC) .. you now have a fifty watt level tuner. if the capacitors have no sharp edges and you change to a larger toroid in type-06 material you have a 100 W capable tuner. TE Fidler NzL
If you want to put it in a metal box you do need a bit of 12mm PE chopping board as a spacer to keep the toroid off the metal because all toroids leak a little and at RF the losses to the enclosure can be considerable if the toroid is clamped to Alum or Steel. the securing of the toroid is best done with a nylon screw and nut or with three cable ties.
Great video build John, thanks for doing this one. I have been thinking of getting this one for a go box with my R4030 QRP radio...
73
Jimmy, ARRL TS, WX9DX
John I bought a three dollar clock kit on ebay, no english instructions, I built it and it works. Not an easy thing to do
Another good one. Like the winding thing.
Thanks for watching and for your comments.
John
Just got my kit.
Since I'm not using it for transmit I can omit the entire circuit board and switch and just build the T match.
Thanks for the tips on winding the inductor too!
73 DE N2NLQ
I soldered a moving-coil meter (100 microampere full scale) in series with a 10 kOhm resistor and put this combination parallel to the LED. Now the point of best adjustment can be found with much more accuracy than with the LED alone.
Helmut, thanks for watching and for your suggestion. ~John
Thanks, I just got the kit ordered and started researching by videos - I will refer back to yours, I am sure!
73's
Thanks for watching and for your comment. Good luck with your kit build. ~John
Hi K7AGE,
Just received my 'Days' antenna tuner here in England. It took 5 weeks to be delivered from China but only cost £8.50. I have printed off the schematic and wondered after winding the main toroid, what is the connection sequence for the 12 taps to the main capicitor?. I have never made anything like this, but don't feel too daunted as your 'you tube' video is very informative. Have you found the LED SWR light to be very effective. I did not realise that this is an SWR warning light and should dim when the SWR is good. Thanks for posting both videos.
Paul
M6MIY Ipswich England.
Thanks John, excellent informational video. The word you were looking for is "Chinglish".
In all honesty, if this kit just fit a bit better together and the instructions were in proper English, there's no real reason why this couldn't be a first timers kit.
I think the bigger issue is really the instructions. All it needs is for one of the Chinese manufacturers to pay a Ham $100 for a couple of hours work tidying it up.
As you say, the pictures are great. Some of it reminds me of my VHF/UHF Quansheng handy.
nice work john I've built several of these chinese kits including the QRP Pixie for $5! Needed to replace the crystal in that one however. Thanks and 73s
+slaznum1 thanks for watching and for your comments. ~John
Winding the toroid in this manner is difficult. I used 0.8mm (AWG 21) enameled copper wire which can be soldered on the outside of the toroid. Then short wires connect to the 12 position rotary switch. A very hot soldering iron is required to melt the enamel.
Good project John. Seemed to work well in the end.
73
Sandy
Sandy,
The tuner did work pretty well which is surprising after all the mix ups in the instructions!
Take care,
John
Great video John!! I wish more people would explain building things like you do. I just emailed you about the schematic. I am thinking of getting one of these. I just got into the QRP bug and just finished building my second Pixie 40 Meter QRP rig. The first one I blew the final, thought I had my 80 Meter dipole tuned with my MFJ 969 tuner using my Vectronics analyzer hooked to it to get the SWR down. Apparently I didn't!! I am building a specific 40 Meter dipole, but would like to have a QRP tuner and have been looking at this one. Again appreciate your videos and enjoy how you explain things. 73 DE Juddie WD8WV
Juddie, thanks for your very kind words. Glad you are enjoying the videos. ~John
W5CYF / TinkerJohn I enjoy watching them quite a bit! I like the idea of being able to make your own equipment. I got the kit yesterday and finish d it up tonight. I hate to say it but what a piece of junk! Put the knob on the inductor messed up the inductor. It no longer clicks, if free spins from A to about F, then clicks to G and I and then free spins to L. I had no problems winding the inductor or the other little one. I was really hoping for a little bit better quality, but as a good friend tells me you get what you pay for. But heck the Pixie works better than the tuner!
Got mine together --- working fine, except for the LED which I can't figure. Certain older tuners used decades ago had a bulb which indicated resonance and allowed their use without a meter; especially with the vacuum tube RF finals which were the standard then. But, best I can judge from the pidgin English instructions, this LED is supposed to go OUT when resonance is reached. In any case, my LED has never illuminated under any condition of (non)resonance (and before some says it ---yes, the LED polarity is correct ---- anode to positive +).
Another construction note is about the tuning capacitors. In the first photo of the manufacturer's partially-translated instructions, the unwired components are displayed with the capacitor terminals pointed down. In the subsequent photo of the wired version, the capacitors have been rotated 180-degrees so that the terminals are pointed upward. Anyone building the kit needs to watch out for this, otherwise they will be un-doing then re-doing their work. Of course the terminals could be left in the unwired configuration and the hookups reversed, but since building this thing relies on copying the photos I don't advise it. I think reversing the leads has no effect anyway, depending on whether the capacitance of the outside leads-to-ground is identical; some of thse little phenolic caps are symmetrical; some ain't.
Never did figure the mechanical tuning knobs out, but lo' and behold I found two extension shafts in the parts box which are made for the espress purpose of extendng the flush shafts of these little "transistor tuning capacitors." So, I'm smokin' in the tuning department.
Last, I should say something good about the kit - other than it does work. That something is the case. Undrilled and unmarked or not, the case is the most superb kit case I have ever laid eyes on! The thing is hard, thick and I don't think anything less than a home run baseball bat swing could crack or chip it. It reminds me of the old Bakelite technology minus the brittleness (you can't chip this thing!), but of course it's not. And, the waterproof claim is real too --- there's even a waterproof gasket to which fits into a recessed groove where the case and its back meets. Of course the holes you drill won't be waterproof, and in any case I haven't heard of Scuba QRP'ing yet. But, I wish all my other projects had cases one-fourth the substance of this one!
P.S - The claimed specs for this toy is 5-watts max for the dummy load, but I never could figure what the max tuner wattage is. Ever figure that one out? It looks like it should handle 10w at a 100% duty cycle, and maybe 5 more watts for a CW cycle. I noticed as I built it that if heavier wire had been used on the main toroid (there is room on the form) and the phenolic caps swapped out for some real air variables, this thing could easilty handle 40-50 watts without getting to hot.
Great video. Just looked you up on QRZ and just about fell out of my chair. Did not know you were in Whitehouse! I live over in Jacksonville, and am the current secretary for the Cherokee County Amateur Radio Club. Small world I guess. Thanks again for the videos and maybe I'll catch on one of the local repeaters. 73 K5WCF
William, Glad to have you following along and thanks for watching my videos. I work mostly CW on 20/40 meters (no room for 80 meter antenna). Perhaps I'll get a chance to meet you in person someday. ~John
great vid!!
Enjoyed the videos, and you should patent that toroid-bobbin method, lol. If it's tricky for a 'ham' then I wonder if I'll ruin it - I have a soldering iron, but the drilling... I have 2-6mm only, looked on ebay - can't find a tools list. Ah well... great videos anyway :)
John, this is my second time to watch your video. My Chinese tuner came in and after opening up the box, it was worse than I thought. The toroids aren't the problem with me - it is the variable caps. Each cap has 3 terminals and 2 sections. One section is about 150pF & other is 50pF, That adds up the 200pF if used in parallel. I was expecting at least 400pF. Oh well. Anyway yours tuned and so will mine, I hope, Speaking of hope - I hope to work you QRP.
David,Hopefully you'll be able to complete your tuner...the instructions are not very clear on several things. Hope to meet you soon....CW of course!John
I just looked ZM-2 ATU and it seems that they are similar designs, so looking the photos of the other and the instructions, it will probably help build this one.
Giovanniram22 Thanks for watching and for your comments. ~John
Few years have passed by John and I hope your well? I'm afraid nothing has changed regarding this kit. Same difficult instructions, same monstrous switches, (I've built a K2 and some Rockmites, but this beats all)! Without your help on this video, I think I would have just given up!! 73s
It appears that they have altered the PCB board slightly as the 51ohm resistors now fit the board, but still found two errors:
1st - the FT 37-43 5 turn/2 turn toroid is incorrectly marked on the PCB but correct on the schematic. (The 5 turns should connect to the Diode trace and ground.)
2nd - the T106-2 large toroid appears to be "upside down" on the schematic. The 10 turns should be the last connection on the switch and the beginning of the 1 turn should be connected to the two variable capacitors. Without this, the 10 turns keep the tuner from minimizing SWR on 14 mhz and higher.
The schematic isn't clear on the variable capacitor wiring either. They have 3 legs. The 2 legs on either side need to connect together. This increases the total range of capacitance.
I use a 50 ohm dummy load connected to OUT and tune to it to start. Then replace the dummy load with the antenna and finish tuning. It does actually work (with my end fed antenna).
Be sure to flip the toggle switch to bypass the SWR meter for normal operation.
Russell, thanks for taking a moment to send along your corrections and suggestions. They are very helpful. ~John
I actually bought mine from a Canadian source and he had included the schematic.
The SWR bridge most closely resembles that of the KD1JV circuit, which I think would be a good source of info, and available from the ALT tuner in the archives of Hendricks QRP.
I don't understand where they came up with their tap info, as I would make it a little more linear and tap it at: :2, 4, 6, 8, 10, 13, 16, 20, 24, 28, 34, 40 as in the VA3IUL tuner.
We'll see if mine works.
Lee, WA8QFE
Francis Thompson Francis, I like your idea and comments. Glad to have you aboard. ~John
For someone who is using this tuner for receive only I suspect that 1/2 watt resistors could be used on the board. That would make it easier to build.
Thanks for watching. Yes, for receive the 1/2 watts work fine. ~John
It would be interesting if someone could make a modification and put an instrument like the ''youkits'' kit to show watts and swr.
I don't know if you figured out but a yl ham on TH-cam pointed out that the diagram was wrong the 10 turn part is position 12 and the first one turn portion hooks to the tuner caps and the swr transformer Labels on the circuit is backwards I believe 2 on the in a different 5 on the out.
Thank You, Thank You, Great Video's, Not hard to do, but you got to know 73's
Mario, thanks for your comment. ~John
M1KTA said he has 2 kits and one board is correct. The board with the error in the cap, you could solder on the back of the board.Just make sure you are not putting it across the secondary winding of the transformer.
Lee, WA8QFE
Francis Thompson Lee, I have an unbuilt kit for the same tuner. I am going to check the board to see if it's been corrected. Thanks for the tip. ~John
Nice video John,
Some of these tuner kits are prizes at the Lobstercon QRP Camping and Hamfest in Maine next week and your instructional videos will be sent along with the kits to the prize winners. Thanks, Jim / W1FMR
Jim,Thanks for your comments. Hope the video provides some help at the hamfest.73John
Great video. Built One Myself Did You Have Trouble Getting SRW circuit Working Properly? Im Getting This Problem With My Circuit Never Got Around To investigating It
I was curious, I notice here we start with ten turns, and then add the other winding's to this with the knob adjustment to gradually add more turns make our loading coil larger. Wouldn't adding a switch and connecting one side of it to the far end of the coil (and thereby using the coil in reverse) extend the range? Where fewer turns are used first, and the ten turn section is added last? I just noticed the last of the coil is electrically free, and this gave me a thought on adding a second range in this way.
That sounds like something to experiment with. That's the fun of building. ~John
Got it all except the construction manual ??
Hi, thanks a lot for these very useful videos. I also purchased the same kit, however I have troubles to follow the schematics provided. In particular the varicaptors have three legs (O-G-A) and I am not sure how to connect them, or from where to where? would you have some more detailed circuit diagram? Thanks a lot!
+perdidoanonimo If you are still interested, I noticed from some of the pictures in the "instructions" that the O and A terminals are jumpered together. Then one lead goes to the G terminal, and the other lead goes to the jumpered O and A. At least that is the way I built mine. But I haven't tested it yet.
I just put one of these together today. I haven't tested it yet. Be carefull when putting the screws into the variable capacitors. I had to put washers on mine because the screws were too long.
Mike Neukam Mike, Thanks for watching and for your comment. How did the tuner work when it was completed? ~John
W5CYF / TinkerJohn I haven't tested it yet. I need to get some more BNC cables first and I'm planning on moving some things around. I'm using a Genesis G11 SDR radio and I need to change computers and set everything up again. It'll probably be a while before I'm all set up and running again.
I'm building this eBay beast too. Anyone considering reducing their net worth by $20 to acquire this Chi-Com people's product should realize that there are no assembly instructions. No manual of any kind comes with the tuner, and the on-line manual is completely undecipherable. It's apparent that the original Chinese text was run through one of those free online Chinese-to-Whatever language translators.
Putting this thing together means that you will have only some photographs and a rather poorly annotated schematic. You really need to know how LC tuner circuits work to succeed at this one. Unless you can look at a part and already know its function and where it fits in a tuner circuit, I don't think you'll be able to handle this one. And, the parts in the kit are different than those shown in the photos.
Watch the too-long mounting screws on the tuning caps. They are flat-headed, but if you countersink them as that design intends the mounting screws will over-penetrate the caps and damage the rotor/stator. The inductor switch leads are too large for the board, so the board will have to be drilled out larger, and like you say the spacing for the 1-watt resistors is too narrow --- but you cannot stand them upright because the board wouldn't fit into the case.
The saving grace of this kit is two-fold, (1) it's cheap, and (2) it's a simple kit with only a few parts. Oh! And on those tuning knobs. I have never in my life seen a tuning knob with hardware on the inside of the knob. I've tried every way I could think of to get the knobs on the shafts, but it ain't happening, The knobs are flush with the mounting panel, and the only solution I can think of are those extension shafts which are made just for the purpose of making the shaft's longer so a knob can be fitted.
Anyway, good review ---- I was hoping you'd get around to solve the mystery of the RoboKnobs! :)
Maybe I'm just incredibly thick, but I'm already stuck on the assembly.
1) the photograph of the wound toroid in the build manual - which they tell me to copy - has a couple extra turns after the final -2-2-2 sequence, and no twisted final -1 tap, with a total of 11 twisted taps and two loose wire ends. That doesn't correspond to the 10-2-3-2-3-3-2-4-2-2-2-1 sequence in the schematic.
2) I don't understand how I'm supposed to orient the switch relative to the taps with only 11 taps-- what do I solder to switch pos 1? The 10 tap, I assume?
Maybe I should just ignore the photo in the docs and follow the schematic. This kit build isn't my first rodeo by any measure, but it feels that way.
Great vid. I noticed that the switch pin-outs aren't explained in regards to which witch tap they go to on the main toroid. My instructions don't include this detail either. Ant clues?Cheers. ;)
Thanks for watching. I can send you a schematic if you don't have one. You can PM me with your email and I can get one out to you. ~John
I have looked at the same tuner awhile ago and thought about getting it and giver a try. Looks to be a neat little setup. :-)
You have a lot more patience than I, that's for sure. The instructions sound bloody funny, good job they included the pictures, as they say 'a picture tells a thousand words'. It would have been good to see the inductor and switch with all of the taps soldered on prior to installation in the box, I can imagine that would have been a nightmare. Still, as you say for $20 you can't really go wrong. You couldn't buy all of those components for $20 down at the local electronics shop. How much power do they say you can put through it? Have you used it on the air?
VK6CS Thanks for taking time to comment. Yes, the tuner works (kind of), there is an error on the PC board and I'll be making an update video in a month or so to show the correct circuit. ~John
Must be warmer in the radio shack then the machine shop today. :D Looks like the original box would have been a very tight fit for final assembly anyway. Half what I get from China has no instructions at all so you were ahead of the game on this project. Any reason to make computer generated dial faces just for reference settings? Another fun video John.
Yep...getting a little cold in the garage so I moved inside for a spell. I will be making a dial face on computer but right now it's just a few labels from a cheap label maker.
Take care,
John
very cool
Thanks for your comments.
John
Lots of Sources for this unit. Not one with the schematic. Picked this up at a flea market but he did nit have the manual. Still looking. The parent company is all in Chinese.
If you need build instructions, contact me via About Me page. ~John
John thanks for the great video as usual, can you supply a link to the build instructions website as I cannot find the link and I have asked the vendors and they are not too helpful in this respect cheers paul
Thanks for watching...Please send me your email and I'll get a copy of the plans out to you.~John
Great video, I have been considering buying this kit. Now that I know it works I will invest the money and time. Thanks, KE0OWS
Thanks for watching. I think you'll find the little tuner works well for what it was designed for. ~John
Starting to build mine. Wish me luck, John! Thanks for the very well needed video. Ron KA5HZV
Great videos and tips, just one question with this tuner, 1 tail I can see where it goes but the other one is a mystery to me, so does it go to the centre pin on the switch along with one of the yellow tails? thanks for any advice.
73's
Thanks for watching, If you send me your email address in a PM message, I will send you the schematic. ~John
Just curious as to what settings you have found on the center dial that correspond to the different ham bands. I ordered one of these and am waiting for the delivery. I will be using your video to assist in building it as the directions are pretty garbled from the poor translation.
Joseph,I usually find the middle range fits most antennas. Your situation may be different, but that was a good place for me to start. Good luck with your build.~John
I've brought this kit but I have come across a issue, please need your advice.. Regarding the windings where do the copper wires get soldered, from the PDF instructions one end is soldered to one tuning side but not sure where the other gets soldered, schematic doesn't show nor the photos with instructions... Many thanks and 73's M6EVD
Thanks for watching. I don't have the tuner any longer, but as I recall one end is soldered to ground and the other to the variable capacitor. Hope this helps. ~John
Thanks for a nice video! Have you tested your kit on all bands 80m to 10m? I assembled my kit this week and it could not match wire antennas other than on 80m, maybe 40m. The reason: inductor seems to be "upside down"! It should not have upper 10-turn section connected to variable capacitors! The inductor should probably be reversed so that 1-turn end goes to capacitors and 10-turn end to ground - so all connections to rotary switch should go opposite way! Otherwise you have always 10 turns even at minimum setting and you can not match various antennas at higher frequencies, say 14...21...18 MHz!
As I noticed this afterwards, I had to remove turns from my assembled tuner, I reduced top section of the inductor from 10 to 1 turn and now it works quite well. The tuning became much sharper when I also connected bottom of the inductor to ground as normally done in T-matching circuit!
YouSepeteus Thanks for watching and for you comments. As you noticed there are some errors in the instructions that I found after the video. The wires were reversed and the PC board has an error. The schematic is correct and if built to that the tuner works fine. 73/John
+W5CYF / TinkerJohn So I'm confused - where do I connect which end of the inductor wire? The only other error I think I found in the PCB was that the # of turns on the little inductor was reversed from the schematic.
+YouSepeteus Yes you are correct
Hi john, thanks for making the video. I've now subscribed to your channel.I have a question for you, or anyone reading that might know.Looking at the schematic, I can see that the free end of the toroidal (at the 10 tap end), goes to the bridge between the two variable caps and that the centre connector of the multi rotor switch goes to ground. However, the schematic doesn't show where the other loose end of the toroid winding goes. Do I ground it? Or is it left open?Thanks in advance for your help !!
It is left open, connected to nothing. the device begins with the ten turns end and the rotatory switch adds more turns to increase the inductance as you rotate the grounded wiper arm around the selector switch. The turns beyond the wiper arm are not in use.
John this is going to seem a silly question to you but when winding the main torroid the begining of the wire attaches to the variable capacitor on the left but when you've finished your windings ,where does the end of the wire go please Have been pulling my hair out for days now so your help would sure be appreciated.
Although i no longer have the tuner and can only go by what I recall, I believe the coil winding went from the variable cap to ground. The schematic is correct and will be helpful. Hope this recollection helps. 73 ~John
Thanks John
Thanks again John - one question - how do you adjust this if you don't already have an antenna analyzer? I'm looking for QRP portable and minimum weight (EFHW most likely) and so want to bring as little along as possible.
Kevin,
Thanks for watching and for your comment. You don't need an analyzer, all you do is first tune for loudest noise level by listening to radio and first tuning the middle switch, then tune the two capacitors on each side. Then key down (briefly) and then fine tune until LED goes out. It has a very fine tuning range, but once you use it a little, it becomes easy.
73/John
W5CYF / TinkerJohn
Thanks for the super fast response! I'm going to order this, seems like it's only U.S. competition is phenomenally slow to ship, I can save $10 and get it just as fast. (If he shipped expeditiously, I'd pay the extra money)
Thanks for the Video John. Can you recommend a tuner kit for someone like me. I've never made a tuner from a kit but I do know how to solder. I'm knew to the ham...just passed my technician exam.
Armando, thanks for watching and congratulations on passing your tech exam. Welcome to ham radio. There are several kits available. Depending on if you will be operating portable or home; qrp or full power, vhf or uf will all make a difference as to what type of kit you need. Suggest looking at 4 states QRP, MFJ and even search Amazon. Hope this helps. ~John
Thanks for the recommendation!
Armando Arevalo QRPGuys.com sells a much easier kit, same circuit, better instructions, for $25.
Hello John, I was wondering if you were able to get the LED circuit to work in order to tune antennas? The reason I ask is because I don't have an antenna analyzer to use (I've heard that the pcb may have an error). Also, one end of the toroid magnetic wire goes to ground, did you solder that ground to the center of the switch (there's a input on the center of the selector switch). Just a Technician here- KG7ODK. Thanks.
Evan Wolfe Evan, Thanks for watching and for your comments. There is an error on the PC board, the schematic is correct. Just follow that and you'll be fine. ~John
W5CYF / TinkerJohn Could you just indicate where the error is on the board, just so we can watch out for it/check it against the schematic, before we start - I have one of these kits on the way £11/$16.
hello john, my variable capacitors are out of use, i need replacement the capacitors. What is the value of capacitors? Can i use metal variable capacitors? Thank you ! Bye
I also have to replace the capacitors - I believe they are 50 - 150 pf
John, I'm trying to figure out how to solder those tabs from the toroid. The switch has 12 connection points plus one in the center. The toroid has only 11 tabs. Thank you.
Adrain, Hopefully I'm not to late in replying. There are several different designs of the tuner. Yours will have one tab not connected. It should not affect operation ~John
W5CYF / TinkerJohn Hi! So have to solder just 11 tabs? 73
Would this work for a magloop antenna? Thanks
+Bence Bujdosó
Bence, This tuner will not likely work on the magloop, those usually require a special tuner. ~John
Just tune for loudest noise.
The little toggle switch at the top, is that a by-pass? I saw the kit online, but don't understand a lick of Chinese!
John,
You are correct, the switch is a by-pass.
The switch changes over to the swr led circuit. It does not bypass the tuner. The circuit contains a dummy load circuit that it uses as a reference to the antenna. When the impedance of the antenna with tuner matches the dummy load, the LED goes out. I wouldn't put much power through that circuit.
Thanks. Mine came with nothing but parts
If you need the building instructions, you can contact me via the email on the "About" page. ~John
John how on earth did u get the capacitor knobs fitted .Iain MM6IXE
Thanks for watching. The knobs are a lot of trouble so i just glued extensions to the caps and put the knobs on that. I no longer have the tuner, otherwise I'd send pics. Hope this helps. ~John
Interesting video thanks. David Byrd KN4BHS
Thanks for watching. ~John
thx for the Vid!!!
73
HB9FVF
It's called Chinglish. There used to be a great website showing examples of really bad and funny Chinglish.
Ever thought of making some decent step by step instructions in writing with photos (like you can find for Pixies) and sell them for download online for $.50 - $1. At 50,000 views I imagine you would get quite a few takers. I personally would be glad to buy some decent instructions I can read as I go rather than constantly viewing portions of a video.
Any one that got a link to a good instruction?
The rotary switch i have has only 3 positions when turning it, is that right?
Peppzz Sorry for the delay in getting back to you, just now getting a chance to do some catch up. The switch should have 12 (or 10) positions. Hope this helps. ~John
Just found the locking spacer on the switch so im good, thank you!
Not a beginner lit
Thanks for the comment. You are correct, the Chinese instructions make the kit much more difficult that it needs to be. If one can follow schematics the kit was not that difficult.
~John
Great Video, where can I download them instructions please De G0TUZ
Thanks for watching. If you click on the About Me tab on my channel and send me your email, I'll get a copy back to you. ~John
Ok, this "kit" is totally goofed. Not only do the photographs show the thing wired backwards, but the PC board has production errors... the reason I couldn't get the out-of-resonance light to come on. FIxing this required cutting traces on PC board and running jumpers to the correct components. The thing is finally running as advertised.
Thanks for adding your comments. Hopefully these suggestions will help others build the kit.~John
W5CYF / TinkerJohn
No problem, John ---- didn't mean to hijack your thread, but I know of no other forum currently discussing this kit. On yours - if you haven't already done it - reverse the wires on the IN and OUT connections using the final assembled photograph as the guide. And the 104 ceramic capacitor is connected to the 5-turn side of the smaller toroid, which is incorrect. Cut the trace linking the capacitor to the 5-turn winding, then reroute that 5-turn wire to the anode side of the 1N60 diode --- just as the schematic shows. You can see that the board is built with errors, but the schematic is correct. I noticed right away that with the way the board was traced, the 104 capacitor was passing all RF energy directly to ground; neither the 1N60 rectifier or the red illumination LED were seeing a speck of it. Once you do this, your red light even works!, although it's an odd function. Apparently the additional SWR circuitry allows you to tickle the tuner with reduced power until you get the thing tune, thereby reducing the risk of damaging your RF final amp. Throw the switch to the left which activates the dummy loaded SWR indicator circuit, and just use a watt or two. Adjust the tuner until the red light goes OUT, then you have minimum standing waves --- your transmitter and antenna are matched. Then, just throw the switch to the right (operating mode) and apply full power which I expect is no more than 15-watts continuous, or maybe 20-watts at 50% duty cycle. I used the tuner in CW mode with a homemade linear amplifier running 22-watts and detected no damage or even appreciable heating. Just remember that the SWR tuneup circuit is only designed to take a couple of watts. And the little tuner performs exactly as advertised ---- it WILL tune a random antenna in the 1-30 mhz range. I used a lab generator and running max inductance the thing will tune well into the AM commercial broadcast range.
Ви пролили світлом на проблеми
JUNK. Do not buy!!!