[Elecraft] [K3] Keyer Pause

[Donald Thompson]

Hi Bruna,
I moved my Leonessa Key from the CW Machine to my new K3 and encountered failures on the dash sometimes.  I think that I have confirmed it to be dirty contact on the Leonessa since the K3 works fine with the Elecraft Hex key.

I would like specific instructions on how to clean this.  I got lots of different suggestions on the reflector but want to make sure I do it correctly and don't damage anything.

Can you also confirm that this key gas gold contacts?

Thanks,
Don KA1KU (KB1YBG)


Sent from my iPhone

On Sep 4, 2012, at 11:46 AM, "David Cutter" <d.cutter at ntlworld.com> wrote:

> It's all about wetting current.  On a building site machine design I used 30mA of dc and a level detector to sense when the switch had been pushed and they lasted years.  A few pA from digital circuits is often not enough to wet precious metal contacts which are open to the ambient.  Try cleaning fluid before using a diamond tipped polishing tool.  Once that thin plating is gone, it will give even more problems.  I seem to remember German silver as a good, hard contact material.  Look at the technology of relay contacts.
> 
> David
> G3UNA
> 
> 
> 
>> 
>> 
>> On Sep 4, 2012, at 7:42 AM, Lee Trout <troutcm at gmail.com> wrote:
>> 
>>> ...I have noticed that my Begali is quite sensitive to dirty contacts. On my
>>> Begali, intermittent operation is a sure sign the contacts need cleaning...
>>> 
>> Hi Lee,
>> It seems you're correct.  I switched to my hex key and the problem went away.  Back to Begali and it returned.  For example my call becomes KAJ.. and 73 becomes 7V as it delays on the dash.
>> I never suspected the key since I have been using it with the CW Machine with no problems.   Perhaps one draws more current?
>> Also, my K3 is in my new radio room, a finished family room 1/2 below grade and with much higher humidity, been from 45 to 70% as I run the dehumidifier.  Just wondering if this may be the cause.  The CW Machine is upstairs with AC and thus very low humidity.
>> Last,  how should I clean the contacts? I think with just a strip of paper but know I must be careful.  Also the Leonessa has the contacts stacked vertical with dash on bottom and hard to reach.
>> 
>> Thanks,
>> Don KA1KU 
>