OpenGD77

VK3KYY wrote: ↑

Sat Feb 06, 2021 8:39 pm

I have a contact who works in a facility with lots of good test equipment.

He has a RD5R, so I will ask him to do some tests, and hopefully he will be able to give me some data about the possible cause of this problem you are experiencing.

Great, thanks!

I installed the firmware version dated 19/1/2020 on the GD77 and on the RD-5R. I measured the UHF output level on a dummy load with a diamond SX-600 in PEP mode. There is not other difference between the two measurements other than the GD-77 needs a SMA gender changer, as the antenna plug is differe...

I have installed the version from 19/1/2020. I still have the motorboating noise with the backlight on. I understand it was not fixed in that version, so this is probably normal. I just wanted to give a data point.

I did not use a digital power meter, but an analogue one.

In any case, the results are much different between a GD-77 and a RD-5R connected in the same manner and both transmitting in DMR, so there must be some difference. The relays also indicate a large difference.

I would like to report what appears to be a bug, specific to the RD-5R. I am using build 20:03:10 from Dec 29 2020. I have both a GD-77 and an RD-5R. Everything appears to work, but I noticed that the DMR repeaters I use give me much lower receive levels on the RD-5R and on the GD-77, up to 10 dB le...

On my GD-77, the ticking sound disappears if I turn down the backlight and use FM. I do not need to turn the backlight completely off, actually. This point out to the backlight being one of the causes, but not necessarily the only cause. I get the sound, albeit reduced, in DMR without backlight. But...

I disassembled the radio today, looked at the back paint contact zones and cleaned it with contact spray. Unfortunately, I do not notice much difference as to ticking noise... sorry.

I can confirm that the noise is independent of the power level. I tried with 50 mW.

The interesting part is that if I use FM and switch backlight off, the noise is gone.

I did a few simple tests between the different radios I have. I am not so sure that the noise is linked to the open firmware. One of my radio has the noise on receive and transmit. It is the one I used the most. The other, including the one with the manufacturer firmware also have the noise, but at ...

I would be happy to lend out a radio if that could help. I am based in Germany.