Three assembly questions

[RN4R]

Hello. Bought tr usdx lo assembly kit. I have some questions about assembly and programming.
1. Where can I see filter coil inductance data? After all, torroids can differ in composition and the number of turns can then be different.
2. Can I change the range from 60 meters to 15 meters for example? as the range of 60 meters is not allowed in our country.
3. I have already assembled the main board and turned it on, my call sign is visible there and the 7 MHz band shows. Should I do more firmware?
Thank you. I'm sorry I don't speak English so google translate

[dl6sez]

Hello OM,

1. There is always a difference in winding, toroid material and PA transistors, so simply do the turns of the toroid coils as given in the manual. A class E amplifier is also changing with FETs due to the small changes in characteristics there. After this you have to optimize the windings, sometimes it is okay and can be tuned by tweaking the turns on the toroids without changing the number of turns. Please look at the videos where Manuel DL2MAN shows how to assemble and tweak them.
2. No you can't change the standard frequencies, but you can transmit where you want to, when you have tweaked the low pass filter.
3. Firmware is okay when you see your callsign no need to change for now.

73 de Chris

[RN4R]

Thanks for the reply, I have assembled the transceiver. Power produces 2-3 watts in all ranges. Reception also works except for the range of 20 meters. There is an incomprehensible whistle and rumble. I don't understand what is the reason. Probably not a very good microprocessor. And it is soldered there manually with a soldering iron, which is not very good.

[RN4R]

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[RN4R]

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[dl6sez]

Hello OM Ilsur,

good to hear it works

For 20m: if you hear the relay clicking after switching to 20m and everything else works, the possible cause there could be a bad contact in the toroid wires in the low pass filter (all 5x inductances). Resolder or unsolder and refit them.

If one band works everything on the Main is okay. If one TX works with about 2W, all there should be okay in PA. So now have a look at the video for tweaking the low pass filters....
Best is to measure Notch first with the help of a Nano VNA or equal equipment.
If you don't have one, you can start tweaking windings of series L in LPF without changing number of turns.
If you squeeze the turns nearer together, the inductance decreases (hope it was not increasing and vice versa if you equaly distribute the windings on the whole core.
If you think you have to tweak the windings number, decrease or increase according to your assumption if it needs to get higher or lower inductance only one winding at a time. As i did it.... please have a look at Manuels video.

73 de Chris

[RN4R]

Completely finished assembling and configuring the transceiver, made a dozen connections with a telegraph. Everything works well. Thanks to developers
https://www.youtube.com/watch?v=_VSk5Bg ... shR4AaABAg