[Elecraft] K3 shuts down

[Bob McGraw]

On many many occasions I have found DC Power Strips to be the fault of 
many issues.  Poor voltage regulation due to added resistance in the 
path is the primary one.  Yes, every connection and contact adds 
resistance.    For this reason, I've always practiced and written, one 
must connect the radio power leads direct to the power supply 
terminals.  DC Power Strips are good for low current applications but 
certainly NOT for the dynamic current demands of a radio.  This is 
regardless of the DC power strip current rating.  And if the DC Power 
Strip has individual fuses or switches, this makes it much worse.  Just 
more contact connections to add resistance to the current path.

73

Bob, K4TAX


On 9/1/2024 12:20 PM, elecraft-request at mailman.qth.net wrote:
> Message: 6
> Date: Wed, 28 Aug 2024 12:24:48 +0100
> From: G4GNX<g4gnx at g4gnx.com>
> To: Elecraft Reflector<elecraft at mailman.qth.net>
> Subject: Re: [Elecraft] K3 shuts down
> Message-ID:<2CC39ED5-2461-4C6A-8BD9-EBC34BBFA414 at g4gnx.com>
> Content-Type: text/plain;	charset=utf-8
>
> My K3S did this a couple of months ago - 40m SSB - 100W. I restarted it and it continued for nearly another month before switching off again. It did it a couple of times more over a week or so, before finally turning off and refusing to turn on again.
>
> On investigation, I realised that I had ?temporarily? connected the K3S power cable to a distribution box, using PowerPoles - bad move. When tracing the cable routing, I pressed against one of the PowerPoles and the radio came back on again. I found it impossible to pull the PowerPoles apart, which was due to the plastic covers being badly distorted by heat. I eventually got round to pulling the PowerPoles apart by force and unfortunately the + connector flew in the air and I haven?t found it yet. ?
>
> However, the contact in the dis-box looks suspiciously like it?s gotten hot and coupled with the other ?evidence? I conclude that the contacts deformed under heat caused by high current spikes (SSB).
>
> Also, my IC-9700 (although connected to a different PSU - via PowerPoles) did the same thing, but unlike the K3S, it just rebooted itself.
>
> I have completely rewired all of the high power cables in my shack directly back to the PSU (Sharman Multicom - 60A) and I?ve had no more problems.
>
> In your case, you?re running 100W for longer periods and that is one possible cause of a premature breakdown. You could save yourself a lot of trouble, by examining all of the power connections, including the PowerPoles on the K3 itself.
>
> 73,
> Alan - G4GNX
> South Coast UK
> Elecraft K4D / KPA500 / KAT500 / IC-9700
-- 
Daddy said there would be days like this!