[Elecraft] K2: Low 8V, and adjusting AGC and S-meter

[DW Holtman]

Kristinn,

I had the exact same problem. I replaced the regulator with one that 
operates at 8.0 VDC and the AGC adjusted correctly. I don't know if they 
received a batch of bad chips, but I used one that I had on hand, not one 
from Elecraft.

Good luck.

Best,
DW Holtman
WB7SSN

----- Original Message ----- 
From: "TF3KX" <kristinn1 at gmail.com>
To: <elecraft at mailman.qth.net>
Sent: Sunday, May 11, 2008 6:25 PM
Subject: [Elecraft] K2: Low 8V, and adjusting AGC and S-meter


>
> Hi:
>
> My K2 #6425 was ordered in February and is now fully operational, with
> almost all measurements and checks within limits.  The only issue is the
> output of the 8V regulator, which is at 7.56V (5.5% down from the nominal
> 8V).  If I am right, this low voltage is the cause for...
>
> a)  AGC threshold adjustment:  U2 pin 5 voltage only goes up to 3.62V, not
> 3.80V;
> b)  S-meter adjustment:  Can never get S-meter LED below #2 or above #9 to
> turn on.
>
> I had to order some spare parts from Elecraft, and to be safe I asked them
> also to send me a tested replacement for the 8V regulator - which is on 
> the
> way.
>
> My questions are...
> - Wouldn't the low 8V level be the cause of the above symptoms (a) and 
> (b)?
> - Any reason I should or should not replace that 8V regulator, anyway?
>
> 73 - Kristinn, TF3KX
> -- 
> View this message in context: 
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> Sent from the Elecraft mailing list archive at Nabble.com.
>
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