Thanks Manuel. I found that after reading all I could find about the (tr)uSDX that there was still a lot I didn't know about what was going on. It seemed to be missing some info. I ultimately filled in the missing info by reading about the uSDX rig design, (I'd jumped into the process at the (tr)uSDX stage and knew nothing about the history with the uSDX.) With that further technical background and some ARRL publication reading about class E amplifier design I finally felt prepared to put my NanoVNA to work tuning my (tr)uSDX. But this video makes the entire process much easier and quicker to figure out how BEST to do it. Nothing beats listening to the designer. I know it's a lot of time and effort on your part, so again thank you. I appreciate the effort you put into doing this design and the videos, everything from the Gerbers, to the BOM, to the How To Assemble and Tune videos.
Some viewers may not fully realize that these are latching relays, and that you preset to the 20 meter band while the power is turned on in order to have the 20 meter resonant circuit switched in after you turn power off to the RF board in order to tune the 20 meter resonator and filter inductors.
I suspected as much given that he switched it to 80m with the mainboard connected and then pulled the power, but thanks for making that clearer. I'm about to do this same process for two RF boards (one Lo, one Hi) so every bit of clarity on how it works is helpful.
You bring up an excellent point.... our responsibility to not cause interference with other signals/bands/etc. And to do this, you think like an engineer. I suppose we all have to at least think like a novice engineer... which reminds me of another hobby of mine. I have a few old, air-cooled Volkswagen Beetles... and in the VW Bug world there is a saying "Volkswagen.... turning drivers into mechanics since 1949!" in our case "HAM, turning operators into engineers since 1901!"
I knew nothing about cars when I bought my first used bug. Four bugs later I could replace the pistons and jugs and be back on the road in a day. It was quite an education.
As a Ham, understanding your kit is requisite in the field. This video gives me a primer on how to best improve it’s (the radio) efficiencies, and appreciate its capabilities & understand it’s limitations. Thanks for such a great kit & video!
Perfect timing. Just completed mine and have too low power, was going to use scope probe with nano VNA but this is brilliant, thank-you for the time and effort with all the radios you have created, I still have the earlier models to construct, everything is ready, it’s just time. 73’s Jules G4UET
This is too cool. I really have to order one soon. I like it too much... even though I told my self I will not brake my rule of not using anything with digital stuff in it or SMA components hahaha. 73. You did a great job with this design.
Finally got my (tr)USDX working the way it should. Its taken a while. The final problem was low output and efficiency on 20 metres. I had to take one turn off each of the 20 metre toroids now about 85% efficiency and 6 w! I also had an audio problem, but that was due to my poor soldering of the inter-board connector.
Congratulations for this great project! May I ask for some information about the future addition of higher bands 17/15/12/10m? I am actually mostly interested in 10m. A 80-10m transceiver, even if in a bigger enclosure would be awesome. Do you have any estimated dates in mind? 73 from PU3TLG.
Is it appropriate, given these things are placed in cars and whatnot, if we have invested in taking the time to do this tuning, to apply adhesive silicone to the coils in their exacted states? Also, what setting were you on with those measures? And can you refer me to the HAM book on where the harmonics should be? I thought I had purchased a pre-built kit, but realized I did not. My IC7000 is in the shop, and feel, that with the solder station and careful effort, I can likely assemble it myself. But I have to admit, there is a lot of tweaking I am witnessing in these videos. I want to thank you for the time you have invested in this series that even gave me a snowball's chance in hell of getting this close to correct. 73 KJ5ECS
Thanks for not just showing how to finetune the power/efficiency with the (tr)uSDX but also simultaneously finetuning my setup using my NanoVNA to measure rf boards. I have built 'adapters' from SMA (NanoVNA side) to ground clamps and measurement tips. (RF board side) This video helped me figuring out that at least one of the 'adapters' was unnecessary to build. Damn I must have been blind. All the rf boards I measure filters from have an antenna connector 😀👼 But good to see we've had similar solutions for the same problem: hooking up a NanoVNA to some rf board. dl2man de dk4amf tnx fer the vid es 73
Hi, what happened to my High TruSDX ? I tried to make the same measurements with the Nano VNA, but I only got a peak at 56 MHz. Thats the notch for the 10 m Band. Do I have to set anything. Normaly the Relais are open without any current.
I just ran across your highly technical video on the little tr uSDX; very nicely done. Question please: Do you recommend this radio vs the QRP Labs QMX CW only for build quality and performance? Thanks, Michael
As the creactor of the (tr)uSDX I am a little biased on that question. I have a QMX and at this point, Firmware of QMX is not yet fully functional (no AGC, no SSB, ) and it is more complicated to build. However: In theory, the QMX has more potential. If it can catch up to (tr)uSDX in practice depends on how fast Hans is evolving his Firmware. Until that point, I will chose my (tr)uSDX over QMX every day, as it simply works as I need it. 73 Manuel, DL2MAN
Hi Manuel, I was wondering if you could explain a bit more how the class E amplifier achieves the linearity needed for SSB operation. Would it be possible to do the same thing for a VHF transceiver? The prospect of a cheap, power efficient, VHF SSB transceiver is very appealing to me. Thanks again for this amazing project.
Possible for sure. I´m just not sure, if we´re anywhere in the near future are going to try something like this. We have ideas for years and no free time....
@@dl2man I am also familiar with this problem. Can you point me to any resources on designing class-E amplifiers? I want to understand how an on/off amplifier can produce a linear output, and maybe I'll even be inspired to build one some day....
I saw these on EBay sold by someone in China. I had the option of buying the kit or one already assembled. If I get the assembled one, will it work right out of the box, or do I have to do something with software first ?
An assembled one comes plug and play. But please read the sellers Text. I´m just the developer and have nothing to do with sales or logistics. I published my plans free of charge, and I am not involved in any sales.
On an assembled (tr)uSDX that I just purchased from Malahit on Amazon, I get about 5.8 watts out on 3560 Khz at 77% efficiency, but only about 2.54 watts out at 79% efficiency at 3960 Khz. Is it normal to have that much drop off of power on 80 meters, or does it sound like this unit has a problem (maybe not tweaked properly?)? This is at 12 volts.
Class E Operation is quite narrow and 80m Band quite broad in relation to base frequency, so yes, this is normal behavior. You can try to tweak it towards the portion of the Band, you use most. In my case, this is CW Portion and it doesn´t matter there.
What will adjusting the inductance on the other three toroids do? You mentioned the choke doing something but I didn't quite understand what. Apologies if that's explained elsewhere.
There´s only 2 Inductors involved per Band. Those are discussed in the Video. Choke inductor acts as 2 things: 1. constant energy source (minimum inductance required, we´re way above required minimum) 2. Blocking RF from DC Line (the higher inductance, the better). The other 2 black toroids are only SWR Transformers, and don´t affect Class E at all. There´s only one right setup for those, and this cannot be tweaked.
Good morning, I apologize in advance for my question which may seem stupid. If I understand correctly, the P.A is protected by your design when there is no antenna. I feel like I don't have the full power of the post. So is it normal that I only have 2.5 or 2.8 watts displayed with no dummy load or antenna when I press the PTT? I specify that I feed in 12Volts. With the dummy load or the antenna, would I have the real power displayed? I know the question may seem stupid but I have the posye but not yet made my antenna. It's to find out if my post is defective. Cordially.
The PA is NOT protected !!! Never ever TX without Antenna or Dummyload. The only instance where you´ll get away with it without damage is when it´s only connected to USB Power Supply. The real power is shown when on 50 Ohms Dummyload.
Is there any option in the radio to LOWER the power? I'm trying to use an external 50 watts amp and can't use it because the 5-6w in 20 meters are too much and over drive it so I wonder how I can lower it to 3w probably? Not permanent ;-)
@@dl2man I thought about that but was concerned about performance. Plus I need to find a source of power lower than 12v which is usually very difficult in a shack where everything is 12v haha. Thanks
Today I saw a guide as to where all the items you can change and how to get to them. Example. Push a button two times then select a certain item an then turn knob to select the item you want to modify.. It appeared to be a flow chart. Can you post a link to it?
Thanks for the video. When I use a dummy load I get a maximum power of 5W When I connect to my antenna I get a maximum power of 6.5W Same pattern on all bands - dummy load is spot on, antenna shows excessively high power Is this normal ?
@@dl2man Thank you for the response. Just to confirm - This is a real value that will damage my (tru)SDX if I use it ? At the moment I am just testing TX for a second or less. Great product btw - it manages to be fun, educational, practical and cute all at the same time, oh and affordable - that's a tough task to pull off but you guys managed it - thanks. There are now 3 of them at our radio club and they are generating a lot of interest.
@@smellthecoffee5314 Well, check your SWR with Dummy Load: Should not be over 1,02. CHeck it with ANtenna: Should not be over 1,5. If that´s the case, your SWR measurement is working and It is safe to work CW and SSB. I´d limit myself a little with stuff like WSPR, as this includes 3 Minutes of constant TX. The Output Power over DUmmy Load is the true value. Output Power over Impedance mismatch is "distorted". It is safe to use, if your SWR is not above 1,5:1. If in doubt, reduce input voltage to lower output power. 73 Manuel, DL2MAN
Great video! I am just waiting for a USBasp in order to get some software onto my (tr)uSDX. I will start with the 3xBS170 but after watching your video I am wondering if the FDT86256 would be a better option when running from 13.8V which the voltage I am using for all transceivers? 73 de Dirk SA4DHT
The Rig works up to 16V without issues. If you replace the FET for another Type, all the Filter Caps and Inductors need to be adjusted. Please see my assembly page for details. dl2man.de/2-trusdx-assembly/
@@dl2man I am aware that the filters need to be changed. I saw a note in the forum that the FDT86256 is more rugged in the presence of high SWR. What is your experience? These days the FDT86256 is of cause harder to get, but I have some and wonder if it would be a more robust solution?
Well, you found the right menu, but if you want to be sure, you should check the readings first. In this Video, I show, how I do my testings: th-cam.com/video/nBPIdE0tRo0/w-d-xo.html
@@dl2man yeah, I did use the link above to build it, but I was asking for the second notch harmonics for the classical bands, since it includes the 10m band and that one is even more "trickier" to tune than the 20m you describe in the video, and the only text about it, that is there is a warning about carefully tuning the second harmonic notch for the 10m band. I really appreciate all the work explaining and even the videos on building the boards without that I would probably be really lost in everything since I'm just starting in this ham radio world and most things look like black magic to me. Thank you for your time and dedication to this project!
@@dl2man Oh, thank you for clarifying this matter! Initially I thought that 15V would be safe, as per manual on your website (where the upper voltage limit is as high as 16V), but yesterday I found your warning on forum to not exceed 14V, and also utilize radio-graded power supply, not just the one from the Walmart shelf. (Just wondering - how many (tr)uSDX reviewers on TH-cam utilize poor AC/DC converters, leading to poor radio performance?) So thanks again, I'll be considering quad lifepo4 pack now. As it happens, yesterday I ordered my (tr)uSDX, and a day before that I passed my first CEPT/HAREC test, so in a couple of weeks my callsign will be there. 73!
I have to adjust the 40m and 80m power can someone point out where the 40m toroid is. 80m is 6.33 95% 40m is 6.38 91% and 20m is 5.48 78%. All with 13 volts input
Hallo Manuel, ich habe meinen High TruSDX in die ewigen Jagdgründe geschickt, bei FT8 und 12,6V. Wahrscheinlich war wohl der Filter nicht richtig eingestellt (Output 2Watt, SWR
Ja, gerade die High Bands sind sehr empfindlich auf falsches Filter Tuning. DIe gute Nachricht ist: Die FDT86256 sind nicht sehr teuer und 1 FDT86256 ist leichter zu tauschen, als 3x BS170 ;) Geringer Aufwand, und Du bist wieder im Rennen. Pro-Tip: Vor der nächsten FT8-Session dann erst FIlter abgleichen auf maximalen Wirkungsgrad und Antenne mit SWR besser 1,5 nutzen. Wenn das nicht geht: Ausgangsleitung reduzieren. Mit USB-Spannungsversorgung alleine (ca. 0,5W Ausgangsleistung) kriegst Du den FET auch ohne Antenne nicht kaputt. 73 Manuel; DL2MAN
@@dl2man schon ausgetauscht. Tut wieder. Nur der Filterabgleich. Habe nur einen Peak bei 56 MHz. :( Konnten die Filter für 28MHz einstellen, Aber was ist denn da los ? ansonsten keine Probleme, Effektivität ist halt nicht so hoch, aber jetzt immerhin mehr als 50 % bei 28MHz. Am Anfang nur 20 %. Das war wohl zuviel vor dem Ausfall.
Thanks Manuel. I found that after reading all I could find about the (tr)uSDX that there was still a lot I didn't know about what was going on. It seemed to be missing some info. I ultimately filled in the missing info by reading about the uSDX rig design, (I'd jumped into the process at the (tr)uSDX stage and knew nothing about the history with the uSDX.)
With that further technical background and some ARRL publication reading about class E amplifier design I finally felt prepared to put my NanoVNA to work tuning my (tr)uSDX. But this video makes the entire process much easier and quicker to figure out how BEST to do it. Nothing beats listening to the designer. I know it's a lot of time and effort on your part, so again thank you. I appreciate the effort you put into doing this design and the videos, everything from the Gerbers, to the BOM, to the How To Assemble and Tune videos.
Some viewers may not fully realize that these are latching relays, and that you preset to the 20 meter band while the power is turned on in order to have the 20 meter resonant circuit switched in after you turn power off to the RF board in order to tune the 20 meter resonator and filter inductors.
I suspected as much given that he switched it to 80m with the mainboard connected and then pulled the power, but thanks for making that clearer. I'm about to do this same process for two RF boards (one Lo, one Hi) so every bit of clarity on how it works is helpful.
A very important point!
You bring up an excellent point.... our responsibility to not cause interference with other signals/bands/etc. And to do this, you think like an engineer. I suppose we all have to at least think like a novice engineer... which reminds me of another hobby of mine. I have a few old, air-cooled Volkswagen Beetles... and in the VW Bug world there is a saying "Volkswagen.... turning drivers into mechanics since 1949!" in our case "HAM, turning operators into engineers since 1901!"
I knew nothing about cars when I bought my first used bug. Four bugs later I could replace the pistons and jugs and be back on the road in a day. It was quite an education.
As a Ham, understanding your kit is requisite in the field. This video gives me a primer on how to best improve it’s (the radio) efficiencies, and appreciate its capabilities & understand it’s limitations. Thanks for such a great kit & video!
Perfect timing. Just completed mine and have too low power, was going to use scope probe with nano VNA but this is brilliant, thank-you for the time and effort with all the radios you have created, I still have the earlier models to construct, everything is ready, it’s just time. 73’s Jules G4UET
I have just received and built mine today, and this video will come very useful as I get below 3W of power.
excellent! exactly what we need. Back to school. Thanks a lot
This is too cool. I really have to order one soon. I like it too much... even though I told my self I will not brake my rule of not using anything with digital stuff in it or SMA components hahaha. 73. You did a great job with this design.
Thanks Manuel!
Great project, very well explained.
Health and success!
Finally got my (tr)USDX working the way it should. Its taken a while. The final problem was low output and efficiency on 20 metres. I had to take one turn off each of the 20 metre toroids now about 85% efficiency and 6 w! I also had an audio problem, but that was due to my poor soldering of the inter-board connector.
Congratulations for this great project! May I ask for some information about the future addition of higher bands 17/15/12/10m? I am actually mostly interested in 10m. A 80-10m transceiver, even if in a bigger enclosure would be awesome. Do you have any estimated dates in mind? 73 from PU3TLG.
Firmware supports it already, and the Values have been published. dl2man.de/2-trusdx-assembly/ From my side: More will not happen.
Is it appropriate, given these things are placed in cars and whatnot, if we have invested in taking the time to do this tuning, to apply adhesive silicone to the coils in their exacted states? Also, what setting were you on with those measures? And can you refer me to the HAM book on where the harmonics should be? I thought I had purchased a pre-built kit, but realized I did not. My IC7000 is in the shop, and feel, that with the solder station and careful effort, I can likely assemble it myself. But I have to admit, there is a lot of tweaking I am witnessing in these videos. I want to thank you for the time you have invested in this series that even gave me a snowball's chance in hell of getting this close to correct. 73 KJ5ECS
Thanks for not just showing how to finetune the power/efficiency with the (tr)uSDX but also simultaneously finetuning my setup using my NanoVNA to measure rf boards. I have built 'adapters' from SMA (NanoVNA side) to ground clamps and measurement tips. (RF board side) This video helped me figuring out that at least one of the 'adapters' was unnecessary to build. Damn I must have been blind. All the rf boards I measure filters from have an antenna connector 😀👼 But good to see we've had similar solutions for the same problem: hooking up a NanoVNA to some rf board. dl2man de dk4amf tnx fer the vid es 73
Thank you for this!
Hi, what happened to my High TruSDX ? I tried to make the same measurements with the Nano VNA, but I only got a peak at 56 MHz. Thats the notch for the 10 m Band. Do I have to set anything. Normaly the Relais are open without any current.
O.K. Set the Band in the TruSDX an than Switch off the Power. After that I can make ameasure :)
I just ran across your highly technical video on the little tr uSDX; very nicely done. Question please: Do you recommend this radio vs the QRP Labs QMX CW only for build quality and performance? Thanks, Michael
As the creactor of the (tr)uSDX I am a little biased on that question. I have a QMX and at this point, Firmware of QMX is not yet fully functional (no AGC, no SSB, ) and it is more complicated to build. However: In theory, the QMX has more potential. If it can catch up to (tr)uSDX in practice depends on how fast Hans is evolving his Firmware. Until that point, I will chose my (tr)uSDX over QMX every day, as it simply works as I need it. 73 Manuel, DL2MAN
@@dl2man Thanks so much for your response; I'll have to order your radio fully assembled from Amazon. 73
Hi Manuel, I was wondering if you could explain a bit more how the class E amplifier achieves the linearity needed for SSB operation. Would it be possible to do the same thing for a VHF transceiver? The prospect of a cheap, power efficient, VHF SSB transceiver is very appealing to me. Thanks again for this amazing project.
Possible for sure. I´m just not sure, if we´re anywhere in the near future are going to try something like this. We have ideas for years and no free time....
@@dl2man I am also familiar with this problem. Can you point me to any resources on designing class-E amplifiers? I want to understand how an on/off amplifier can produce a linear output, and maybe I'll even be inspired to build one some day....
I mean is it 20,40,80 across the bottom and 30,60 the two on top?
I saw these on EBay sold by someone in China. I had the option of buying the kit or one already assembled. If I get the assembled one, will it work right out of the box, or do I have to do something with software first ?
An assembled one comes plug and play. But please read the sellers Text. I´m just the developer and have nothing to do with sales or logistics. I published my plans free of charge, and I am not involved in any sales.
@@dl2man Ok, thank you !
How do you calibrate the NanoVna to tune this?
Normal SOLT Calibration for the frequency range I´m looking at. 73 Manuel; DL2MAN
On an assembled (tr)uSDX that I just purchased from Malahit on Amazon, I get about 5.8 watts out on 3560 Khz at 77% efficiency, but only about 2.54 watts out at 79% efficiency at 3960 Khz. Is it normal to have that much drop off of power on 80 meters, or does it sound like this unit has a problem (maybe not tweaked properly?)? This is at 12 volts.
Class E Operation is quite narrow and 80m Band quite broad in relation to base frequency, so yes, this is normal behavior. You can try to tweak it towards the portion of the Band, you use most. In my case, this is CW Portion and it doesn´t matter there.
Thanks !
What will adjusting the inductance on the other three toroids do? You mentioned the choke doing something but I didn't quite understand what. Apologies if that's explained elsewhere.
There´s only 2 Inductors involved per Band. Those are discussed in the Video. Choke inductor acts as 2 things: 1. constant energy source (minimum inductance required, we´re way above required minimum) 2. Blocking RF from DC Line (the higher inductance, the better). The other 2 black toroids are only SWR Transformers, and don´t affect Class E at all. There´s only one right setup for those, and this cannot be tweaked.
Good morning,
I apologize in advance for my question which may seem stupid.
If I understand correctly, the P.A is protected by your design when there is no antenna.
I feel like I don't have the full power of the post.
So is it normal that I only have 2.5 or 2.8 watts displayed with no dummy load or antenna when I press the PTT?
I specify that I feed in 12Volts.
With the dummy load or the antenna, would I have the real power displayed?
I know the question may seem stupid but I have the posye but not yet made my antenna. It's to find out if my post is defective.
Cordially.
The PA is NOT protected !!! Never ever TX without Antenna or Dummyload. The only instance where you´ll get away with it without damage is when it´s only connected to USB Power Supply. The real power is shown when on 50 Ohms Dummyload.
Is there any option in the radio to LOWER the power? I'm trying to use an external 50 watts amp and can't use it because the 5-6w in 20 meters are too much and over drive it so I wonder how I can lower it to 3w probably? Not permanent ;-)
Easy: Run (tr)uSDX with lower voltage. Lower Voltage = Lower Output-Power @nearly same Efficiency
@@dl2man I thought about that but was concerned about performance. Plus I need to find a source of power lower than 12v which is usually very difficult in a shack where everything is 12v haha. Thanks
Today I saw a guide as to where all the items you can change and how to get to them.
Example. Push a button two times then select a certain item an then turn knob to select the item you want to modify..
It appeared to be a flow chart. Can you post a link to it?
dl2man.de/4-trusdx-manual/
Thanks for the video.
When I use a dummy load I get a maximum power of 5W
When I connect to my antenna I get a maximum power of 6.5W
Same pattern on all bands - dummy load is spot on, antenna shows excessively high power
Is this normal ?
This is normal when your Antenna has another Impedance than 50 Ohms, also known as "SWR not 1:1".
@@dl2man
Thank you for the response.
Just to confirm - This is a real value that will damage my (tru)SDX if I use it ?
At the moment I am just testing TX for a second or less.
Great product btw - it manages to be fun, educational, practical and cute all at the same time, oh and affordable - that's a tough task to pull off but you guys managed it - thanks.
There are now 3 of them at our radio club and they are generating a lot of interest.
@@smellthecoffee5314 Well, check your SWR with Dummy Load: Should not be over 1,02. CHeck it with ANtenna: Should not be over 1,5. If that´s the case, your SWR measurement is working and It is safe to work CW and SSB. I´d limit myself a little with stuff like WSPR, as this includes 3 Minutes of constant TX. The Output Power over DUmmy Load is the true value. Output Power over Impedance mismatch is "distorted". It is safe to use, if your SWR is not above 1,5:1. If in doubt, reduce input voltage to lower output power. 73 Manuel, DL2MAN
@@dl2man Thats very helpful information - thanks. 73 Paul, M7MGK
Great video! I am just waiting for a USBasp in order to get some software onto my (tr)uSDX. I will start with the 3xBS170 but after watching your video I am wondering if the FDT86256 would be a better option when running from 13.8V which the voltage I am using for all transceivers? 73 de Dirk SA4DHT
The Rig works up to 16V without issues. If you replace the FET for another Type, all the Filter Caps and Inductors need to be adjusted. Please see my assembly page for details. dl2man.de/2-trusdx-assembly/
@@dl2man I am aware that the filters need to be changed. I saw a note in the forum that the FDT86256 is more rugged in the presence of high SWR. What is your experience? These days the FDT86256 is of cause harder to get, but I have some and wonder if it would be a more robust solution?
What setting enables you to see the efficiency of the rig ??? Found out go to the SWR setting and turn the multi to PWR - EFF
Well, you found the right menu, but if you want to be sure, you should check the readings first. In this Video, I show, how I do my testings: th-cam.com/video/nBPIdE0tRo0/w-d-xo.html
@@dl2man thank you that is a very good video ....well done ..
Hi, friend! When I press gear it doesn't show power. What is it connected with?
Displying PWR works only in CW and only in Straight Key Mode
@@dl2man Thank you! Happened!
Hi! I was wondering what are the second notch values and others to consider for the classical bands?
Does noone ever consider having a look at the resource #1 for this project ? dl2man.de/2-trusdx-assembly/ I have published everything.....
@@dl2man yeah, I did use the link above to build it, but I was asking for the second notch harmonics for the classical bands, since it includes the 10m band and that one is even more "trickier" to tune than the 20m you describe in the video, and the only text about it, that is there is a warning about carefully tuning the second harmonic notch for the 10m band.
I really appreciate all the work explaining and even the videos on building the boards without that I would probably be really lost in everything since I'm just starting in this ham radio world and most things look like black magic to me. Thank you for your time and dedication to this project!
Hi! I've got a question for you. You've been testing it @12VDC, and already the power's been too high. What would happen if you try 15VDC?
Release of magic smoke, that´s trapped inside PA FETs.
@@dl2man Oh, thank you for clarifying this matter! Initially I thought that 15V would be safe, as per manual on your website (where the upper voltage limit is as high as 16V), but yesterday I found your warning on forum to not exceed 14V, and also utilize radio-graded power supply, not just the one from the Walmart shelf. (Just wondering - how many (tr)uSDX reviewers on TH-cam utilize poor AC/DC converters, leading to poor radio performance?)
So thanks again, I'll be considering quad lifepo4 pack now. As it happens, yesterday I ordered my (tr)uSDX, and a day before that I passed my first CEPT/HAREC test, so in a couple of weeks my callsign will be there. 73!
May I please ask, where I can purchase the official kit from.
I am in England UK. Thankyou
The cheapest method is to join the buying group in the forum. The other way is to buy in the official stores that are also in the forum. 73 CX1GU
@@gonzalocamper9924 Thankyou M0DPV
dl2man.de/where-to-buy-trusdx/
Why not put one transistor in the output stage, for example rd15 on a small radiator
Not suitable for class E Operation
I built a classic bands and none of them are even close maybe I'm doing something wrong i followed the instructions exacly
I have to adjust the 40m and 80m power can someone point out where the 40m toroid is. 80m is 6.33 95% 40m is 6.38 91% and 20m is 5.48 78%. All with 13 volts input
Please refer to my page: dl2man.de/2-trusdx-assembly/
where you find all the schematics with all the details, you´re looking for. 73 Manuel, DL2MAN
Who's/which nanovna-f did you buy?
Deepelec
Will any nano via work. Or F the better one to use?
Any Nano VNA will work
Hallo Manuel,
ich habe meinen High TruSDX in die ewigen Jagdgründe geschickt, bei FT8 und 12,6V. Wahrscheinlich war wohl der Filter nicht richtig eingestellt (Output 2Watt, SWR
Ja, gerade die High Bands sind sehr empfindlich auf falsches Filter Tuning. DIe gute Nachricht ist: Die FDT86256 sind nicht sehr teuer und 1 FDT86256 ist leichter zu tauschen, als 3x BS170 ;) Geringer Aufwand, und Du bist wieder im Rennen. Pro-Tip: Vor der nächsten FT8-Session dann erst FIlter abgleichen auf maximalen Wirkungsgrad und Antenne mit SWR besser 1,5 nutzen. Wenn das nicht geht: Ausgangsleitung reduzieren. Mit USB-Spannungsversorgung alleine (ca. 0,5W Ausgangsleistung) kriegst Du den FET auch ohne Antenne nicht kaputt. 73 Manuel; DL2MAN
@@dl2man schon ausgetauscht. Tut wieder. Nur der Filterabgleich. Habe nur einen Peak bei 56 MHz. :( Konnten die Filter für 28MHz einstellen, Aber was ist denn da los ? ansonsten keine Probleme, Effektivität ist halt nicht so hoch, aber jetzt immerhin mehr als 50 % bei 28MHz. Am Anfang nur 20 %. Das war wohl zuviel vor dem Ausfall.
Vers good 😊
TU 73 GL.