FDMduo no receive #fdm-duo


AndersH
 

Hello,

Please do not overlook that Vianney not too long ago mentioned that a THS4509 in typical configuration is used
It is not seen in the schematic that was shared here.

The beyond awesome dynamic range and spectral purity of the DUO/DUOr owes a lot to this chip even if the AD converter always plays the first violin, so to say.

All the best!
Anders H.
SM6-8439


db4ta@...
 

Thanks a lot !
I hope will find the issue 

73 de Alex
DB4TA


DAVID IW5BNL
 

Hi Alex

Here input stage of duo.
It was shared here on the group.

Ciao
IW5BNL 
David

Il Sab 10 Set 2022, 12:57 db4ta via groups.io <db4ta=arcor.de@groups.io> ha scritto:
Hello, everyone,
yesterday my FDMduo suddenly stopped receiving while i am working digimode FT8.
My guess is that it was static electricity from the antenna. (It rains and eg 100km away was a thunderstorm)

So I decided to reset the Duo to system defaults to rule out own mistakes.
The FDMduo also shows a noise of -80dbm, but even if I transmit with another radio on the receiving frequency,
nothing is displayed and nothing can be heard except hissing neither in the software nor on the speaker/display.
Are there surge arresters on the receiving board that cause a short circuit?
Unfortunately I don't have a circuit diagram for the RX board, otherwise I would have looked myself.
And I couldn't find anything in the support area from Elad.
Had anyone the same issue ?


Regards Alex
DB4TA


db4ta@...
 

Hello, everyone,
yesterday my FDMduo suddenly stopped receiving while i am working digimode FT8.
My guess is that it was static electricity from the antenna. (It rains and eg 100km away was a thunderstorm)

So I decided to reset the Duo to system defaults to rule out own mistakes.
The FDMduo also shows a noise of -80dbm, but even if I transmit with another radio on the receiving frequency,
nothing is displayed and nothing can be heard except hissing neither in the software nor on the speaker/display.
Are there surge arresters on the receiving board that cause a short circuit?
Unfortunately I don't have a circuit diagram for the RX board, otherwise I would have looked myself.
And I couldn't find anything in the support area from Elad.
Had anyone the same issue ?


Regards Alex
DB4TA