TUNE function contact closure

Skip to first unread message


May 18, 2021, 6:46:01 PM5/18/21
to Hermes-Lite

Hello, I would like to enable contact closure output from HL2 when pressing TUNE button in PowerSDR. Is there a way to configure GPIO to do that?
I need contact closure for enabling 10dB attenuator to reduce external amplifier power from 270W down to about 15W. Drive setting is already set to 1 or lowest setting for TUNE function. 
Another way to achieve what I want is to enable GPIO contact input that will place PowerSDR into TUNE mode. I guess that can be done via CAT commands? So I will need some kind RS232 controller to tell PowerSDR to go into TUNE?



Alan Hopper

May 19, 2021, 2:18:29 AM5/19/21
to Hermes-Lite
Hi Anton,
another solution would be to tweak PowerSDR so it scales the iq data to extend the drive range to allow lower output.
73 Alan M0NNB 

Reid Campbell

May 19, 2021, 3:15:26 AM5/19/21
to herme...@googlegroups.com
Hi Anton,

I think the signal you require is already there and is used to initiate an ATU tune. Have a look at


The you are interested in the ATU RQST signal which will change state on a PowerSDR tune request. I'm not sure of the exact logic but there was some discussion in the following thread.


Hope that helps. The Wiki is a bit light in information in this area, so if you get it figured out, drop us a few line on your findings and we can add it to the Wiki.


You received this message because you are subscribed to the Google Groups "Hermes-Lite" group.
To unsubscribe from this group and stop receiving emails from it, send an email to hermes-lite...@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/hermes-lite/201c5d49-c2fa-4c11-be6c-63b8a89a11bfn%40googlegroups.com.


May 20, 2021, 5:52:24 PM5/20/21
to Hermes-Lite
Thanks for all your help, I will report back later once I get this working.
Reply all
Reply to author
0 new messages