[Elecraft] Problem with K3 #353 at Field Day

[Ron D'Eau Claire]

Actually, the K3 is supposed to work FB all the way down to 11V. I haven't tried 11 V, but I've run mine at full output well under 12 V with no problems at all. That's not recommended in SSB and most data modes since the IMD of the power amp isn't as good at the lower voltages, but it should still work FB and meet all Elecraft specs at the lower voltage. 

Is it possible there were brief, severe drops in the voltage caused by the varying loads that were too short to show up on the voltage display?  Such a drop could easily trigger a shut down. Since it's an unexpected power-down, it might also confuse the MCU causing lost data that can result in other operational anomalies when power is restored as well. 

Ron AC7AC 




-----Original Message-----
From: elecraft-bounces at mailman.qth.net [mailto:elecraft-bounces at mailman.qth.net] On Behalf Of Hector Padron
Sent: Tuesday, June 30, 2009 6:00 AM
To: David Y.
Cc: Elecraft at mailman.qth.net
Subject: Re: [Elecraft] Problem with K3 #353 at Field Day

I agree with Dave,I had in the first half an hour a problem at FD with my K3 and it was a "Pyramid" PS that had a poor regulation,the K3 quit and it went off by itself and few mins later we figured out after powering it back that voltage at the K3 display was droping from 13.8 to 12V when keying on CW at 110W out,so we switched PS to an Astron 35A and it remained at 13.8V droping only 200mV.Then I spent 6 hours with no problem at all with it.
Aparently voltage regulation is very important to keep the K3 up and running properly.My two cents to the topic.
 
AD4C