Search found 24 matches

by HB9HJF
30 Nov 2022, 09:24
Forum: General Information
Topic: Mic Gain
Replies: 21
Views: 1844

Re: Mic Gain

I've had success using a Yaesu MH-34 and an adapter I built to the (tr)uSDX mic socket. I haven't (yet) wired up the speaker in the MH-34 but hte mic and PTT are working exactly as expected, and I've had reasonable readability reports. I've also successfully used a cheapie Aliexpress special microph...
by HB9HJF
26 Nov 2022, 15:42
Forum: Troubleshooting
Topic: (tr)uSDX with flrig and fldigi
Replies: 1
Views: 145

Re: (tr)uSDX with flrig and fldigi

Are you providing line-level or headphone-level input to the transceiver? Most of those that are using a soundcard to interface with the transceiver are making sure to not overload the input as a headphone output is far too high a voltage range for the microphone circuit not to clip on input, and th...
by HB9HJF
26 Nov 2022, 15:38
Forum: Troubleshooting
Topic: TX on ssb on ptt without speaking on 15 meter only
Replies: 3
Views: 206

Re: TX on ssb on ptt without speaking on 15 meter only

@ve2rn Can you clarify the problem you're seeing? Your description is a little ambiguous, and I'm having trouble parsing what you've written.

Is it that you can transmit on 15m only and are unable to transmit on the other bands?
by HB9HJF
23 Nov 2022, 08:14
Forum: General Information
Topic: Assembled 8 band 80-10 (tr) uSDX
Replies: 6
Views: 586

Re: Assembled 8 band 80-10 (tr) uSDX

The listed vendors on https://dl2man.de/where-to-buy-trusdx/ are the only ones that are correct, and that page is canonical for vendor authorisation. From that page, the only current Amazon vendor authorised is https://www.amazon.com/dp/B09YH2V2ZP (Malahit) but they do not yet carry the hi-band conf...
by HB9HJF
14 Nov 2022, 22:22
Forum: General Information
Topic: Valid Firmware
Replies: 1
Views: 278

Re: Valid Firmware

From here:
https://dl2man.de/3b-trusdx-firmware/
check the changelog, the current release and beta firmware changelogs are listed there:
by HB9HJF
14 Nov 2022, 22:18
Forum: General Information
Topic: advice on that surface-mount component please
Replies: 1
Views: 189

Re: advice on that surface-mount component please

Exactly which component are you referring to? Most of the current kits don't need a surface mount component to be soldered and that the user assembly is for the through-hole components and toroids. The assembly video does refer to a component that was not readily available when the group-buys were o...
by HB9HJF
14 Nov 2022, 22:15
Forum: General Information
Topic: Assembled 8 band 80-10 (tr) uSDX
Replies: 6
Views: 586

Re: Assembled 8 band 80-10 (tr) uSDX

The three versions are (-meter bands): 80/60/40/30/20 - the "Low Config" 20/17/15/12/10 - the "High Config" 80/40/20/15/10 - the "Classic Config" (without the WARC bands) There's no 8-band option, nor is there expected to be, without a lot of rework of the radio board a...
by HB9HJF
14 Nov 2022, 22:09
Forum: General Information
Topic: Trying to buy an assembled unit
Replies: 2
Views: 209

Re: Trying to buy an assembled unit

Usually the Aliexpress and Ebay sellers will contact you via direct message asking you whether you want your callsign assigned into the radio.
by HB9HJF
02 Nov 2022, 12:26
Forum: Troubleshooting
Topic: Where to buy good bs170
Replies: 4
Views: 296

Re: Where to buy good bs170

https://www.digikey.com/en/products/detail/onsemi/BS170/244280 will also work. If Mouser or Farnell or Digikey have counterfeit components, it'll be a really bad state of affairs. Pretty much any of the "standard" component suppliers should be able to furnish you with real parts, and most ...
by HB9HJF
31 Oct 2022, 21:50
Forum: Troubleshooting
Topic: TX power issue & missing serial number
Replies: 4
Views: 218

Re: TX power issue & missing serial number

And confirming the power output with testing the resulting peak-to-peak voltage with something like an oscilloscope if you can use one... Some dummy loads will have a DC voltage tap (capacitor + diode) to give an approximation of the RMS voltage. The 20W dummy load from QRP-Labs has exactly this, an...
by HB9HJF
30 Oct 2022, 11:57
Forum: General Information
Topic: is the Chinese uSDX a clone of (tr)uSDX?
Replies: 3
Views: 388

Re: is the Chinese uSDX a clone of (tr)uSDX?

To my knowledge, the Chinese clone is their "development" offshoot of a previous incarnation of the "make the QRP-Labs QCX an SSB radio" (the origination of the (tr)uSDX project), where the original modifications to the QCX modification have been over-simplified and made much wor...
by HB9HJF
24 Oct 2022, 07:52
Forum: Troubleshooting
Topic: In RX carrier on recieve Freq - no FET's
Replies: 3
Views: 181

Re: In RX carrier on recieve Freq - no FET's

Local oscillator being seen on nearby sensitive receivers is relatively normal and to be expected. Given you're seeing the carrier when in receive only, the transmit path isn't in scope and grounding or putting a 50ohm resistir across things there would have absolutely no effect. It would normally b...
by HB9HJF
22 Oct 2022, 13:19
Forum: Troubleshooting
Topic: No power on transmit (PWR 0.00W)
Replies: 39
Views: 2007

Re: No power on transmit (PWR 0.00W)

I am now suspecting that the spares that I got from Digikey are not good quality. I removed the non-functional FET, soldered on a replacement, put it together, attached dummy load and using the three battery pack for ~11V, I got CW output into the dummy then a quick ramp down to no watts output. Ano...
by HB9HJF
22 Oct 2022, 07:09
Forum: Troubleshooting
Topic: No power on transmit (PWR 0.00W)
Replies: 39
Views: 2007

Re: No power on transmit (PWR 0.00W)

little bit over 6 amps.(...) 50Vpp = 6,25W Out. 13V*6A =78W in..... So Efficiency is 8% and abt 72W are being disappated in your poor FET. This is why it dies.... If it was a misunderstanding and only the Current in the moment when it died: Use current limitation to prevent that. As soon as somethi...
by HB9HJF
19 Oct 2022, 22:17
Forum: Troubleshooting
Topic: No power on transmit (PWR 0.00W)
Replies: 39
Views: 2007

Re: No power on transmit (PWR 0.00W)

I managed to blow another FDT86256 mosfet this morning in the high-config rig. I was calculating the efficiency of the rig, with 13v supply (my portable lightweight battery which is a car battery jump starter), into a dummy load, with my Rigel monitoring the output voltages. PA bias max had been set...
by HB9HJF
17 Oct 2022, 20:45
Forum: General Information
Topic: Posted new 1.0(n) schematics to Facebook (tr)uSDX group
Replies: 2
Views: 239

Re: Posted new 1.0(n) schematics to Facebook (tr)uSDX group

Editor note: Spelling mistake (trivial of importance). Page 7; section on "Simplified Filter Design"; line 5 word 4; "concidered" should be "considered" Nothing else popped out when I was unintentionally wearing my unfortunately over-active copyeditor hat when looking a...
by HB9HJF
13 Oct 2022, 21:10
Forum: General Information
Topic: Output power on different bands
Replies: 9
Views: 1268

Re: Output power on different bands

Theoretically should still work with ~15V; I'd try not to put more than the standard 13.8V into it to keep within the safety margins available.
by HB9HJF
13 Oct 2022, 21:07
Forum: General Information
Topic: Good results from using a (tr)uSDX.
Replies: 3
Views: 430

Re: Good results from using a (tr)uSDX.

^ I like this one. Wednesday, I took the Low-Band config out portable, attached to an Aerial-51 807HD hanging about 8m above the ground. I had tried to respond to a QSO from a guy in Bavaria with my 817 but he reported poor modulation, so I changed over to the truSDX and was able to make the QSO. Th...
by HB9HJF
13 Oct 2022, 20:54
Forum: Troubleshooting
Topic: No power on transmit (PWR 0.00W)
Replies: 39
Views: 2007

Re: No power on transmit (PWR 0.00W)

Right, digikey order arrived with the replacement FET (and a stack of capacitors to repair a mate's audio amplifier). Some time with a hot air rework station and a few bits of kaptan tape later, the faulted FET was removed, and the replacement soldered into place. Quite an easy exchange at the end o...
by HB9HJF
06 Oct 2022, 19:41
Forum: Troubleshooting
Topic: No power on transmit (PWR 0.00W)
Replies: 39
Views: 2007

Re: No power on transmit (PWR 0.00W)

<hands held up>

I'm in definite need of practice with my Rigol, and I also need to get more quailty sleep.
This is what I get for leaving it about two years since using the oscilloscope last.

Thank you for the pointing!

;)
:)
by HB9HJF
06 Oct 2022, 11:50
Forum: Troubleshooting
Topic: No power on transmit (PWR 0.00W)
Replies: 39
Views: 2007

Re: No power on transmit (PWR 0.00W)

I had a feeling I didn't have the probe 1x-10x slider set correctly, so that would instantly explain that.

Good catch.
by HB9HJF
06 Oct 2022, 11:49
Forum: General Information
Topic: Good results from using a (tr)uSDX.
Replies: 3
Views: 430

Good results from using a (tr)uSDX.

Yesterday I went for a bit of /p playing with radio, and I had my first proper QRP contact. I had wanted to test, configure, and tune a few antennas that I had built up over the past few months in the apartment, as well as try to fune tune an alternative portable setup. Normally I would use my FT-89...
by HB9HJF
06 Oct 2022, 10:19
Forum: Troubleshooting
Topic: No power on transmit (PWR 0.00W)
Replies: 39
Views: 2007

Re: No power on transmit (PWR 0.00W)

I appear to also have killed the FDT86256 mosfet in my high-band (tr)uSDX, with an SWR of 1:1.4 indicated on my Daiwa analogue meter. I was characterising the efficiency of the unit, and it just stopped transmitting after a few PTTs of ~5 seconds. Breaking out the trusty Rigol, I could see that I wa...
by HB9HJF
28 Sep 2022, 11:03
Forum: General Information
Topic: Baofeng/Retevis/Kenwood Hand Mic Adapter Cable (Amplified!)
Replies: 6
Views: 1160

Re: Baofeng/Retevis/Kenwood Hand Mic Adapter Cable (Amplified!)

Thinking of the Yaesu tiny hand mike.. I had built a patch lead adapter to get my Yaesu MH-34 mike to work as a microphone, and it's working quite well for me. I obtained a 3.5mm TRRS breakout board, and soldred on 30cm of wire with a 3.5mm TRS male plug on the end. Then, I used heatshrink to secure...