It has been some time since I have written of my MKARS80 QRP kit. It is still going well and I took the plunge recently and added a relay to disconnect the speaker before applying PTT.
This has, no surprise, removed the feedback howl I was getting when I use a speaker/microphone.
The modification to include the extra relay was not all that easy. I needed to cut a top side track, remove a capacitor and file the case a little as well.
When I get a chance I will draw the circuit showing where the relay fits in to it all.
I have also got a blue back-lit display to fit as well. To fit a back-lit display requires a bit of work as the display is about 3 mm thicker, so the main board needs to sit 3mm further from the front panel. This means the connectors on the panel need to move 3mm as well.
Because of the RF socket and DC power switch I use getting the board in and out is not as easy as it once was.
While I have the board out adding the new display I will adjust the speaker socket and make it the same height as the microphone socket and make a new rear panel as well.