OpenGD77 on the Baofeng DM-1801

[Ik0nwg]

I think I may have blown up the UHF PA on my DM-1801

I can hear the Tx from the DM-1801 with my GD-77 on both VHF and UHF, but on UHF I found I can't connect to my hotspot or to a repeater.

So I measured the power output on UHF and its 0W (no power at all)

I checked the current consumption during Tx for 50mA, and on 2m it is only around 90mA, but on UHF its 800mA

I think probably the PA FET is short circuit

luckily so you have more time to devote to 77 .... I'm kidding of course !!!
Ciao

[m1dyp]

I think I may have blown up the UHF PA on my DM-1801

I can hear the Tx from the DM-1801 with my GD-77 on both VHF and UHF, but on UHF I found I can't connect to my hotspot or to a repeater.

So I measured the power output on UHF and its 0W (no power at all)

I checked the current consumption during Tx for 50mA, and on 2m it is only around 90mA, but on UHF its 800mA

I think probably the PA FET is short circuit

oh no. that is bad news. (not that i'm going to get one, i'm sticking with the gd77)

[VK3KYY]

I think this ends my attempt to port to the DMR-1801, because I can’t can’t justify spending another $100+ on a radio I will probably never use.

[TA2ISO]

Is there any possibility that you can add a donation page for this project so we can fund it ? Thank you.

[VK3KYY]

I think perhaps now the radio may not be damaged.

Possibly some of the connections are wrong, which control the PA.

I have swapped the UHF and VHF PA control pins, and I can now create some power on both VHF and UHF, but I now have some other problems, because I don't think the radio will receive.

I will need to do some more testing later, after I finish work.

[EB3AM]

I think it may be necessary to look at this problem from a perspective. Allow some time and resume again. These devices are so small that we can run into problems simply because the data bus is slightly moved.
It's really complicated to do anything on this scale.

[VK3KYY]

Yes.

I think I need to leave this and think about it

[VK3KYY]

I made another video of the DM-1801, showing some operation of the OpenGD77 on this hardware and also a lot of information about the hardware and the differences with the OpenGD77 on this radio


youtu.be/36GWlDZrJ2E

[m1dyp]

fascinating insight

[EB3AM]

I made another video of the DM-1801, showing some operation of the OpenGD77 on this hardware and also a lot of information about the hardware and the differences with the OpenGD77 on this radio


youtu.be/36GWlDZrJ2E

Right now I couldn't hear the video but I saw that the work you did is huge. You have the screen working, the RX working, and I still think the TX should work too.
When I leave work, I can hear the explanations ...
Don't leave the project, you're almost done!