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VK6CS
Australia
เข้าร่วมเมื่อ 20 ก.ค. 2014
Playing around with amateur radio. A few hopefully useful tests and tips inspired by questions heard on the air.
Update: MINI1300 Antenna Analyser/R&S ZVH4 Comparison... Take 2.
The issue was the calibration. Once the 'open, short and 50 Ohm' calibration was done the MINI1300 followed the R&S far more closely. Personally I doubt I would buy one as I hate touch screens. If a bead of sweat drops onto the screen it goes off and does something else. That said, the results from the MINI1300 are certainly good enough for amateur radio use. Apologies for the extremely poor production of the video, I didn't have much time to spend on it so it was just done quickly on the floor with the hand held camera. I'll leave the previous video up as some people may get similar whacky results and will be relieved to know it's most likely just a calibration issue.
มุมมอง: 13 434
วีดีโอ
A Quick Look At The Response Of A Mini1300 Antenna Analyser
มุมมอง 18K4 ปีที่แล้ว
How does a budget antenna analyser stack up against a professional unit. I thought I would see if the MINI1300 would show results that were close to a professional unit... Update: th-cam.com/video/THG035LiUkY/w-d-xo.html
High Voltage Fun At The HARG (Hills Amateur Radio Group)
มุมมอง 1.7K5 ปีที่แล้ว
One of the guys had access to a HiPot testing device so we connected it to some capacitors. We tested the air-spaced capacitor shown in the video and two vacuum caps. One vacuum cap was fine and the other appeared to have a bit of air inside it. The video clips don't join together too well so I just uploaded the air-spaced cap test as a stand alone video.
Me At Work Driving And Rambling...
มุมมอง 8586 ปีที่แล้ว
I thought I had better upload something to show I'm not dead. I will be getting back into the amateur radio videos in the new year, unfortunately other stuff that's further up the priority list is absorbing all my free time at the moment.
What Are You Likely To Hear On 137Khz...
มุมมอง 2.9K6 ปีที่แล้ว
I heard some guys talking about what antennas to use on 137KHz today. I had never listened to that band so I thought I would take a listen and see what sort of activity was there. Ok, I was only using an FT857 but I think it showed me all I need to know. I won't be bothering with 137KHz personally. It's easy to listen to this band as most HF radio receivers go down to at least 100KHz. My old FT...
More Bucking Around... This HT Voltage Is More Like It
มุมมอง 6736 ปีที่แล้ว
This transformer gives the voltage I'm looking for. Now... how to fit it into the amplifier power supply space.
Bucking And Boosting Transformers... Good Heavens
มุมมอง 4.1K6 ปีที่แล้ว
I had never heard of bucking and boosting transformers before...
Old School Radio... My NOS RK (GK) 71s Have Arrived
มุมมอง 8726 ปีที่แล้ว
I can see why people say these look a lot like 813s. The idea is to triode connect them in parallel in series with the paralleled GU-81M screen grids to provide AM. And yes, I do know they're pentodes and not beam tetrodes.
VK6PM's "Pre Loved" Pi Tank ATU...
มุมมอง 3.6K6 ปีที่แล้ว
Peter VK6PM picked this ATU up for $10 at a recent hamfest. I think he was robbed... seriously though, with a bit of cleaning and component rearrangement this would be a nice little ATU that could take at least 100W.
This Choke Will Do
มุมมอง 1.1K6 ปีที่แล้ว
I wound another choke on a toroidal core I had handy but still had to move the dip in the response to a band of frequencies between 10m and 6m where it wouldn't bother the amp. I measured it... 169.9uH.
Testing A Protection RF Choke
มุมมอง 3.4K6 ปีที่แล้ว
It's a good idea to check the response of any choke you're going to put across an amplifier output.
I can't Respond To Comments For Now... Sorry Guys
มุมมอง 7326 ปีที่แล้ว
Every time I click on a comment to respond to it... it disappears.
Another Unboxing... It Must Be Xmas In January
มุมมอง 4086 ปีที่แล้ว
As I made a few unesessary mods to the GS-35B amplifier due to dodgy test gear I decided to treat myself.
Checking The Heater Filaments On The GU-81Ms
มุมมอง 8176 ปีที่แล้ว
Checking The Heater Filaments On The GU-81Ms
Heat Damage To Mag Loop Tuning Cap Housing
มุมมอง 1.4K7 ปีที่แล้ว
Heat Damage To Mag Loop Tuning Cap Housing
The RFI CD990 Broadband UHF Mobile Antenna
มุมมอง 5557 ปีที่แล้ว
The RFI CD990 Broadband UHF Mobile Antenna
So, What Changes Did I Make To The GS-35B Amp...
มุมมอง 1.2K7 ปีที่แล้ว
So, What Changes Did I Make To The GS-35B Amp...
Cheap And Cheerful World Band Radio... Digitech AR1780
มุมมอง 6K7 ปีที่แล้ว
Cheap And Cheerful World Band Radio... Digitech AR1780
Thanks for the presentation. I don't know how much power you are intending to put through the tuner; I understand it's for a qro (1500w or more). But then, the band switch, (a ceramic type?) seems inadequate to handle the power. I don't know if you completed the L match later. De VU2RZA
Thank you for this video. I bought 12.6 volts power supply and was concerned of the voltage drop when transmitting, but it seems it will be okay.
Maybe perhaps it is best to get familiar with Both units then Make the video. This way you don't look like a moron write?
I got 4 of these valves and retrofit a Bauer 707 AM tx. They actually work pretty good, but the pair needs twice the G2 current than that of the 4-400s in the RF section. The plate modulators needed a bit more G1 negative bias to tame them for class AB1. Doesn't quite make 100% modulation, probably due to the extra G2 current requirement. Interesting valves tho. I hope to make a vid of it soon. 73!
I have 1mm stainless cable which I use for the top elements on my dipole. It seems to work well enough. I used simple screw connectors to connect it to the feeders. I coated the connections with hot melt glue to help prevent water corrosion. I have a friend who used stainless cable for his end fed wire and he seems to be happy with it. Best wishes from New Zealand. ZL3ABX.
thank you G6MMD
What is the part# of the professional calibration dongle and how do we get one? How much $$? Thanks Kindly!
Is the FP-RP meter between Tx and ATU or between ATU and feedline to antenna? If former, how much of tde 5% increase was lost in the ATU? If latter, how of the 5% increase sdows up as a 0.2 dB increase in radiated RF?
I still have my roller coaster and variable capacitor I used to use. At times I still do. L inline and C from the long wire or vertical to earth. For some lengths of wire It was better to put C at the other end of L. I used to tune for maximum r.f. out using an r.f. pickup meter at the aerial before I made my resistive SWR meter. My amateur friend was horrified! He was still horrified when I didn't calibrate the meter and just tuned for the lowest reading. After 5 years I did calibrate it. I found that most r.f. out didn't necessarily coincide with the lowest SWR. I'm only talking a fraction more out as you showed. Somebody's receiver would not notice. Nothing above 5 Watts here. G4GHB
If 4 tubes in parallel, how much watts we can take ?
I find it quite hard hard to solder, steel wire antenna.
Pee on it..i dare ya..lol😅😅😅😅
When you change the range on a vna you need to calibrate again for the best accuracy
Just stumbled on this. What an amazing QSO both in subject matter and atmospheric conditions!
Curious how a double tap on the FUNC button gets access to power level?
This is a very interesting circuit arrangement and to anyone watching this video 8 years later at 1st glance the circuit looks flawed but after doing some analysis on it, you'll understand it. So basically the circuit has the resistors in series upon intial power up, that part is easy to understand but the contacts appear to be bypassing the resistors. So you ask shouldn't the coil voltage be dwindling down until it eventually drops out???🤔 But the relay actually puts the resistors in parallel at the top and bottom of the coil allowing power to flow through the coil to keep it energized and provides full voltage to the load at least that what my analysis concluded. I have no clue what the voltage rating or current draw of this coil is either. But Great Video and Job!!! Do you experience any relay coil dropout long intervals of time??
Hello , Congratulations ! I am a beginner in mobile CB. I have just finalized my mobile CB registration with a DX27 helical antenna (1m80) + MC KINLEY+ KL-203P. So I have a beginner's question for you.👇 You must start by configuring (tuning) your antenna in "Tune" mode ('Tune' button activated) to lower the TOS/SWR, do we agree? Then, when the antenna is tuned with the MC KINLEY Tx linear amplifier, I can return to "ByPass" mode (BPS) and use (modulate to AM/FM/SSB) my CB radio? Sincerely
You sound like you could be on the radio yourself
Very few hams know the difference between a cavity duplexer and a diplexer.
you were very helpful, you took your time, talk slowly, pointed out details, really made scense..very helpful..newbe KD9ZWT
I'm in Canberra, I was taking photos of this building with a big HF dipole on the roof, a 4 wire one. I got home and looked up the building, it was a defence contrator that sells defence radios. I will not be taking any more photos there lol.
hi dgreat info say not under stand after gett i get the swr correct ...i noitice the receiver i ge ts real quite not understand that what you guys think
Wow, to miss the "Z" match. 👎🇬🇧
I think the radio sounds could be heard from there. If it's true, it will be so amazing and mind blowing.
The mfj manual says to do it the first way. Ty
There has to be a better way to power a light up there. Solar? I suppose its all obsolete tech nowadays so it does not really matter.
None of the three involved devices is going obsolete any time soon. We need towers to spread radio signals over long distances, we need visual features like lights on towers to guide planes away from obstacles and terrain, and we still use transformers to couple AC power. They're elementary tools we use to manipulate electromagnetic radiation, not just old technology.
The MFJ manuals differ on that point. The MFJ-949E manual advises you to set the maximum capacitance and minimum capacitance possible for a good SWR. I've followed those instructions and got nice results when using my 11 meters T2LT antenna. I was able to tune and get signal out from 10 to 30 meters. Anyway, the more inductance, the more fiddly the tuning is.
They both are reading for AVG power which is easy for a cheap meter to do , I bet if you had the BIRD PEP modification and then compared that to the REVEXs shitty capacitor PEAK mode and did some AM swing and SSB comparisons it would be COMPLETELY different..
can someone else explain the rings? like are they safety protocol for something? what do they do. all I heard was something with 220v. are they used for disconnecting power? I'm lost
The rings transfer AC power to the lights on the tower without also connecting the mast itself to the AC power source, which would result in some fireworks.
@@chri-k thank you.
In case you want to learn more about it, it's called an Austin transformer
Hi, Did you ever check the other traps on the analyser and record the pF capacitors required to have the antenna resonant please?
i'm quite impressed that those can be even 90% efficient (based on a quick google search) - i would have assumed that it was much lower based on the lack of a core as well as the huge amount of space between. i wonder how strong the stray magnetic field would be from this as well.
@@chri-k you’re right - i should have said there are two separate cores. regular toroidal transformers have both windings on the same core.
@@vinylcabasse I guess I misunderstood what you meant I still don't think the stray field would be very strong though ( well, as much as you can call something connected to a radio mast "not strong" )
What i find more interesting is how is this supposed to work ( at 90% efficiency ) when the windings are perpendicular to each-other
There's actually only one core. The lower ring holds a core, toroidally wound, while the upper ring just holds a regular ring coil... further spaced, but still wrapping in the same direction through the same core as the toroidal windings.
@@jercos wow. that makes complete sense.
Numpty russian with plants? I know exactly which video you're talking about, lol
What does "hot" mean in this context?
Connected to a live source of electricity. In other words, hot = it will burn you. Just electrically.
The entire tower is hot with RF and is above ground so far as RF. Think of an old school CB antenna. The entire antenna is insulated from the car body, and fed at the base with coax. Now think of THAT as a 70KW am tower. Much higher voltages and highest at the top
I thought it was a Folded Monopole (aka Unipole) but looking closely i see the base insulator is still there along with all the guy eggs so yeah not the same but similar principle. De N7MSD
Far out. How lossy would that be?
maybe 5-10% at most? toroidal transformers encapsulate the majority of the magnetic field internally, the only place for losses to go is in heating the core itself.
but in the manuel, it states, it need 13,8V with tolerance 1,5%. so that means min 11,8 V and max 15,8 V. It states otherwise damede can occur
Austin ring transformer to be precise. Its just an air core transfomer with a huge air gap between primary and secondary windings.
The core is rarely air... in fact it's all in the lower ring, with the primary winding spiralling around it. The secondary winding is a straightforward wrap around the secondary ring, coupling it to the (air-gapped) core in the primary.
Looks like an effective lightning arrestor of the two rings at the bottom. A good bolt and there would be a nice spark between the rings.
You don't want that to happen though.
@@chri-k I wouldn't, but it could happen anyway. The impedence between the two coils must serve some function though.
I wonder how driving up to the fence with a couple of large transformer coils in the back rectified leading to a battery bank would go? Surely there's some thick waves to ride there!
Not very well. Power fall off with the inverse square. There's no such thing as a free lunch. Hence one toroid being literally inside of the other.
@@etherealrose2139 The fall off is exponential? If the power is high enough surely there is something left to gather? Not free of course, well I'm not paying anyway but that's semantics. . .. Over time if it's enough to overcome charging resistance + power stored is still + But I concede, the time it would take to pay for the copper in the coils alone is too much, let alone the bank ect
Austin transformer. That's a new one for me. Fascinating.
70 Kilowatts. I am jealous. I only have 2KW - BUT I use a 10.5 db gain antenna (Kt34XA upgraded to KT36XA) which becomes 22KW effectively, according to my db calculator. So I don’t feel quite so inadequate. VE6MRV
I wonder how many years it took to Realize that this was the way to do it when the radio was invented.🤔
Well not specifically this But it's one of the many setups
More cool stuff I didn't need to know, like mercury rectifier tubes for the subway trains.
Thanks - something else I didn't know about!
It looks like the precision of the Calibration load, short and open plays a significant part in the VSWR accuracy of the Mini1300. Problem is that cal kits are very very expensive. I guess with the cal kit that comes with the Mini 1300 we get what we pay for.
The Chinese guys are at their best repertoire. Mini 1300 is actually a misused version of my (EU1KY) original design of a shortwave and 2m analyzer. The mixers used in it are not intended to work above 500 MHz. Also consider that everything above 200 MHz is measured on 3rd harmonic of both the signal an LO (the measured signals are 20 db lower than normal as a result, but still yield a good result), and everything above 600 MHz is measured at 5th harmonic (at the noise floor I think).
1. It's a paint tin. 2. The instructions are on the can.
I’d like to use your demo. You have an antenna to one side of the meter. Is anything connected to the other side?
51 dB of isolation on 70 cm is more than enough for a 50 watt rig, that would represent somewhere around 397 microwatts at the input of the 2 m side. Even if you had a rig capable of 100 w on 70 cm it would still be more than enough
That was fascinating. Thanks for posting. Any idea why you measured slightly more RF power out despite a higher SWR? Seems counterintuitive. 73
I found it too on my set up. Maybe true resonant point of an aerial? G4GHB
@@bill-2018 When I match my vertical antenna, I can't select max C. If I set max C, no amount of I will bring the SWR down below 3. I have to start at mid C, then I can find a suitable I to get the SWR below 3. Then I can get the SWR down to 1.0 with a little more C on both sides. One oddity I have observed is that sometimes I get a little more forward power when the SWR is slightly above 1.0 (roughly 1.2-1.3). I can't explain it, but that's what I see on the 945E meter. Someday I would like to understand this better. 73
@@nateitkin8279 I had (still have) for many years a long wire with a roller coaster and variable capacitor to tune it and an r.f. pickup meter at the aerial. When I built my resistive SWR meter I found a tiny difference between the lowest SWR and maximum r.f. out. Very tiny! No-one at the receiving end would notice. Watch Dave Casler on his Y.T. presentation on Ask Dave number 221. He explains SWR and resonance and inductive and capacitive effects on aerials. 73, G4GHB
Please link ?