Topics

dB level and TX timings

conchobhair.ofearghail@...
 

Hi all,

I built the D4D kit a couple of days ago and it worked well. I didn't make any QSOs just yet, but the band conditions are not good so this isn't a problem.

Yesterday, however, I powered up the transceiver and I noticed some issues. You will see in my screenshot that the received power level is at 54dB. Previously it was at about 23dB, and I was able to receive a lot of FT8 transmissions.

Secondly, you will see that the transmission times start one second later than they are supposed to. Previously they were transmitting at :00, :15, etc. without any problems. This happens in both versions 2.0 and 2.1 of WSJT-X. I also noticed that the transmission duration seems shorter than it previously was, maybe lasting about 11 seconds.

Both of these problems began yesterday. At one point I turned on the power to the transceiver and it did not power up: neither the RX or TX lights went on. After a couple of attempts, the device powered up. Occassionally, WSJT-X throws an error about input audio not being found.

Has anyone else every had any of these problems, or know how I might be able to troubleshoot?

Regards,
Conor EI6GSB

conchobhair.ofearghail@...
 

Hi all again,

After some more investigation I believe this simply may be a case of the transceiver overheating. I opened the case to inspect the board to see if there were any signs of component damage, and everything looked fine. I powered up the transceiver and I still experienced the original problem, but after a few minutes the TX timings returned to normal and the dB level dropped down to about 23dB.

My radio shack got very warm over the last couple of days (over 30 degrees C) and I while troubleshooting I opened the door to let the room cool down for my own personal comfort. I think that this, combined with the black, heat-absorbing enclosure of the transceiver caused the components on the board to overheat and not function correctly.

Thanks to the nature of the enclosure and the board, the D4D transceiver may lend itself to a cooling system modification for people operating in unusually warm climates.

Thank you, too, to Adam for developing the kit: it was fun to assemble and I'm looking forward to making some QRP contacts!

73,
Conor EI6GSB

Adam Rong
 

Hi Conor EI6GSB,

Thanks for reporting this. I have never met this before. If you have spare part, you can try to swap NE602 to see if it is better. Also, check if you have properly attach the final transistor to the rear cover to help heat sink.

Thanks,
Adam

Thanks,
Adam


On Mon, Aug 5, 2019 at 2:32 AM <conchobhair.ofearghail@...> wrote:
Hi all again,

After some more investigation I believe this simply may be a case of the transceiver overheating. I opened the case to inspect the board to see if there were any signs of component damage, and everything looked fine. I powered up the transceiver and I still experienced the original problem, but after a few minutes the TX timings returned to normal and the dB level dropped down to about 23dB.

My radio shack got very warm over the last couple of days (over 30 degrees C) and I while troubleshooting I opened the door to let the room cool down for my own personal comfort. I think that this, combined with the black, heat-absorbing enclosure of the transceiver caused the components on the board to overheat and not function correctly.

Thanks to the nature of the enclosure and the board, the D4D transceiver may lend itself to a cooling system modification for people operating in unusually warm climates.

Thank you, too, to Adam for developing the kit: it was fun to assemble and I'm looking forward to making some QRP contacts!

73,
Conor EI6GSB



--
Thanks,
Adam Rong