[Elecraft] [K3] power switch problem

Tue Aug 5 14:01:01 EDT 2008

David,

Your problem sounds EXACTLY like the one I had with my K3 (#96).  I went 
through the same sequence of events as you seem to be experiencing. 
Initially, the K3 started turning back on by itself; then later it wouldn't 
turn off at all, and had to be unplugged from power to turn it off 
completely.  When it wouldn't turn off, the LCD remained dimly lit, but no 
audio, etc.  Removing power and then plugging power back in again 
effectively recycled the radio, but the "power button" was not used at all. 
For a time the K3 would suddenly return to normal operation with the power 
switch functioning correctly, but this happened only a few times, and didn't 
last for very many cycles.   Other than the problem of powering the radio on 
and off, the radio worked just fine.  All of this sounds like what you are 
also experiencing.  Gary Surrency at Elecraft had me check various voltages, 
etc., but nothing turned up the problem.  They even sent me a new front 
panel to install, but that wasn't the problem either.  Ultimately I had to 
return the K3 to Elecraft, as they felt it was probably something on the 
main board that would have to be serviced.  The repair itself was performed 
by Rene in Aptos.  He determined that there was a problem with a "leaky" 
component, on the I/O board I believe.

In any event, Elecraft is aware of this issue, and can readily solve it. 
Hopefully they can do it now without you having to return the radio, which 
would be more of a problem for you since you are in the U.K.  I suggest you 
contact either Gary or Rene at Elecraft support.  You might mention to them 
that we have corresponded, and that your problem seems identical to the one 
I experienced.  In your case they may just send you a new I/O board, 
assuming I am correct that it was where my problem existed.  There 
apparently have been a couple of other similar cases that may not have 
involved the I/O board, but still had the same symptoms.  Changing the front 
panel apparently solved at least one problem that I am aware of.  If it is 
the I/O board or front panel, you probably wouldn't need to send the radio 
back to Elecraft.  The upside of returning the entire radio is that, besides 
fixing your problem, they will go over it thoroughly, and probably make any 
mods that have come out since your radio was shipped.  They did that for me. 
My K3 is performing perfectly now.

Hope this helps, or at least gives you some comfort.  In any event, I doubt 
seriously that your friends who borrowed your K3 did anything wrong.  It was 
just coincidence that the problem occurred while in their possession.  I bet 
they are feeling awful, thinking they might have caused the problem.

Let me know if you have any other questions.

Dave W7AQK

----- Original Message ----- 
From: "David Ferrington, M0XDF" <M0XDF at Alphadene.co.uk>
To: ""Crafters"" <Elecraft at mailman.qth.net>
Cc: "K3Support" <k3support at elecraft.com>
Sent: Tuesday, August 05, 2008 6:20 AM
Subject: [Elecraft] [K3] power switch problem

> My K3 appears to have developed a power switch problem - it won't turn 
> off.
> While away on Scout camp last week, I allowed another 2 hams to work  the 
> K3 while I was not present (one is quite young and the other an  adult) - 
> later on, one of them noticed that the K3 had turned itself  on (after 
> they had turned it off and walked away). The K3 was working  correctly for 
> the first few days and as far as I know, was not  'bounced' around while 
> sitting on the table during the week. All  functions appear correct except 
> for this.
>
> After investigation, I found I can not turn it off. Pressing the power 
> button results in one of the following behaviours:
>
> Most common: LCD just shows background colour (light is on), LEDs are 
> off, effectively the rig is off (no AF etc), but the LCD is not and I 
> can't turn it back on with a press of the power button.
>
> Occasionally: K3 turns off correctly, but then turns back within a  matter 
> of seconds.
>
> Less occasionally: as above, but turns back on after a few minutes.
>
> Rarely: Appears to turn off as per first scenario, but LCD flickers.
>
> To resolve this, I have to pull out the power cord and plug it back  in, 
> in which case the K3 turns on - so it's like the power switch is 
> permanently on.
>
> This is not the ALARM function. In fact, I tried the alarm to see if  it 
> would turn on correctly - it won't, but it did bleep at me when I  pulled 
> the power out the back and plugged it back in.
>
> I have tried a 'master reset' holding the power switch in, it make no 
> different, doesn't reset and doesn't turn off etc.
>
> In preparation for the reset, I went through and noted all the config 
> settings, changing a couple on the way. After that, the K3 turned off  ok, 
> but came back on after a few minutes.
>
> Holding the power switch while applying power results in the LEDs  coming 
> on, but nothing else.
>
> I thought this might have been a problem with dampness, but the rig  has 
> been in my indoor shake for 3 days now. I also considered supply  voltage, 
> since at camp I was using a L/A battery, but its back on the  13.615v 
> supply now (I have a Medusa Research Power Analyzer).
>
>
> I'm about to install the KRX3, so will be taking it apart, but would 
> prefer to resolve this first.
> Any suggestions?
>
> This has been working perfectly since December.
> 73 de M0XDF, K3 #174
>
> -- 
> Study without desire spoils the memory, and it retains nothing that it 
> takes in.  -- Leonardo da Vinci
>
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