[Elecraft] K3 - stuck at MCU LD we upgrading software

[James Walker]

Yours is not the Astron power supply I was using. Mine was the 35A, transformer style, not switching, with dual meters. I’m still using it for other radios with no problem. And yes, I did check the voltage reading on the K3/100 and it did reduce severely under any load, even QRP. That’s a strange quirk in the equipment but I think that’s it.

Jimmy Walker
WA4ILO
Macon, GA

On Jan 28, 2017, at 2:26 PM, N2TK, Tony <tony.kaz at verizon.net<mailto:tony.kaz at verizon.net>> wrote:

Hi Jimmy,
Tnx for the info. I have a 35A switcher that loafs along. As I never have both K3's transmitting at the same time I am not taxing the supply.
W3FPR got me on the correct track.

In your case, di d you check the voltage on the K3? Maybe you had a problem with a connection in the power supply? Down in the Caribbean periodically we have to take apart the Astron linear power supplies and clean the contact surface on the two bolts feeding the 12V output. They develop a little bit of resistance that drops the voltage under a load.