No RX on any bands + no TX if on 12V

[OZ5ZX]

Hello everyone, the newbi here. Yeah i say newbi coz its my first ever small build like this with SMD and all that.

Well now that you guys know i am total on deep water here, i can start asking my questions.


TDLTR: No RX on any band, good TX on CW, TX on SSB is low and sounds like an old punk band, and inside speaker dont say a pip, but headset do.

First off what have i done so far.

I have build the kit, following Manuels video on YT, and do to i diden have any 0.35mm wire home yes i did T1 and T2 with 1:7 turns.

I then powered it up via USB (5V) coz i diden want to go full power on the first try. And there was life, in the screen that is

I then jumped around the menu for abit to find my way around the system, and man is it simple and head on, love it.

The hooked up my antenna (FD4 Windom) and jumped to FT8 on all 5 bands, but hey wait a min, there is no sound, no sound at all... :/ Okey i graped my headset, and then oh yeah there is sound, but wait that sound, sounds like any other radio on SSB with no antenna on.

First thing to look at no RX on any bands.

I then powered on my FT991A (on a DL) and linked a DL to the truSDX to test TX on CW. And lord behold, there is TX, sure way way off frq but its there, about 0.5W and an eff from 76 at the lowest read band to 89 on the highes. So yeah abit of tinkering is needed but ill get to that. Ah yeah forgot, TX in SSB sounds really bad and low, like a demo song from an old punk band, like everything think turned to 11+
There are nothing happening at all with running it on my 3x 18650 pack. SWR: nav3 something it say on the screen

I then jumped on here to have a good read on all the things others have found out, but never really got someing that i can use, well maybe if i was a skilled tech dude id understand, but tbh i diden.

I then did what i normaly do if my builds (Big normal size componets) Resolder everything, rewired ever core on the board, used sand papir to get the best clean ends to solder to the board, clamed everything togeater, powered it on. And..... Yeah nothing still the same.

I then reflashed my firmware, what do i know, maybe it like a pc, if you add some new hardware best to reinstall windows/linux. Still the same.

No i am at the point, where i am thinking really hard if the project was a to big thing for me, coz i dont have the knowhow to pinpoint whats going on.


I really hope there someone here who can point me in the right way, or hak even in anyway.


Anyways the build it self, i really loved doing, it was a good challens, buuuut doit again, nah i think i need to make some more Jostykit's before i jump on to something like this again, but but but i am not giving up on this guy, i am deturment to make atleasted one QSO on SSB with it

Thanks for reading til the end

Vy 73 de OZ5ZX // Jeff

[dl6sez]

Hello OM,

nice to hear you have done the kit ,
but a can you please write your questions and problems short and precise next time?
We all do this in our free time with little time.... not a story necessary to conclude whats wrong

The ssb audio is not as good as on KenYaeICs trxs, thats normal.
Please don't do tx if obviously something is wrong with the connection of the whole circuit to the antenna,
because you don't hear anything on your normally working antenna in rx!
Keep your 5V USB supply until everything works correct.

Your symptoms are from my knowledge problems with bad solder joints on enameled wires especially on T1 and T2, due to this bad connections you will only hear noise. Also the swr showing is a sign for this problem.
But if you already have a problem at T1 and T2 please have a look at all toroid enameled wire solder joints, they can easily have not a real contact if you did this for the first time or without much practice.

That the speaker does not do anything should be a problem of the headphone jack. Maybe it is damaged.
I would suggest to keep it for now and do all work with headphones until everything works.
The mini speaker is also from my point of view only an emergency speaker. I always use headphones with (tr)uSDX.

73 de Chris

[OZ5ZX]

Hello Chris.

Thanks for the info and heads up, normaly ppl just ask me, what have you done so far ill keep it short then.

T1 and T2 rewired, rest of the coils are all tested, all solder joints resoldered, new SMA conector, rig reset and reinstalled firmware.

No RX from antenna on any band, but RX from signal genarator, but really really weak S3 at -25dBm.

Vy 73 de OZ5ZX // Jeff

[dl6sez]

Hallo Jeff,

relays are clicking at start and with every band change?
Sometimes 14 pin connection between the two pcbs had a problem at rf pin, but normally only when it is worn out a little bit.
Try short tx in cw on 14MHz it should give around 500mW (250mW ok because you didn't align the windings yet) into dummy load. It should now show power and measure swr if selected in menue. Values are not 100% correct but it should show not "nan" or so. If there is not a normal swr/power reading then we still have a solder joint contact problem at a toroid wire. (Measure rf power with external power meter or oscilloscope at dummy load around 10 to 14Vpp if you want).
Hm, maybe there is also a cold solder joint at the LT6231 (U9) or SN74cbt3253 (U6) ICs.
Happened also very very rare.
Last thing is rx mute switch Q1 to check.

My 2 Cents in what often was a problem
73 de Chris

[OZ5ZX]

Hello again.

Yes relays are clicking at start and with every band change.

Tested the TX no pwr out and swr on rig shows 1.00 for 1 sec and then jump to nan0, and thats on every band.

I have had a skilled electronic repair guy, do a run over of the PCBs looking for bad solders both on the SMDs and on the solder job i did, he then did some tests for propper connetions, and show me how to use a signal genarator He did tho say that his more more moving to a fakt that it might be one of the IC/chips that have had a fail from the start, coz no matter what charge we make, the outcome is uncharged

Ill be going over the IC's again my self, to see if i can spot something, like a cold spot.

Thanks again Chris for taking the time to help out

73 de OZ5ZX // Jeff

[Ohwenzelph]

viewtopic.php?p=3244#p3244
To trouble shoot receive, does help if you have an oscilloscope