K2 AGC THRESHOLD

[bill KE5KWE]

Hello All:  

This probably has been asked and answered before but I couldn't find it in the archives.  I Set the AGC Threshold and could only get 3.644 volts out of R1 the potentiometer.  Should I be concerned that I did not get 3.80 volts ?

Thanks for the help.

Bill
KE5KWE

[Sarah K.]

Hmm, I went through that a couple weeks ago and I ended up needing to
replace the 8-volt regulator. Elecraft sent me a new one. Check the
output voltage on the 8-volt regulator (LM2930T-8) and see how close
it is to 8 volts.

I'll be interested to see what the more experienced builders have to
say about this... I wouldn't have thought it would be all that common
a problem!

Sarah AF6FH


On 12/13/07, bill KE5KWE <[hidden email]> wrote:

>
> Hello All:
>
> This probably has been asked and answered before but I couldn't find it in
> the archives.  I Set the AGC Threshold and could only get 3.644 volts out of
> R1 the potentiometer.  Should I be concerned that I did not get 3.80 volts ?
>
> Thanks for the help.
>
> Bill
> KE5KWE
> --
> View this message in context: http://www.nabble.com/K2-AGC-THRESHOLD-tp14329860p14329860.html
> Sent from the Elecraft mailing list archive at Nabble.com.
>
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[David Woolley (E.L)]

bill KE5KWE wrote:
>
> This probably has been asked and answered before but I couldn't find it in
> the archives.  I Set the AGC Threshold and could only get 3.644 volts out of
> R1 the potentiometer.  Should I be concerned that I did not get 3.80 volts ?

I'd say it is a little on the low side, but the error is less than 5%,
so there is a good chance that it is OK.

The target value is pretty much the end stop value when all components
are at the centre of their tolerance bands, so around half of the K2s
shipped are likely to be unable to reach the full 3.8 volts.

In the case of the other reply, their 8 volt regulator was actually out
of its 5% tolerance band.

--
David Woolley
Emails are not formal business letters, whatever businesses may want.
RFC1855 says there should be an address here, but, in a world of spam,
that is no longer good advice, as archive address hiding may not work.
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[Jim Stoneback]

I had the same problem; could only get 3.7 v with R1 cranked all the way to
the stop.  My 8v regulator put out 7.9 v.  At the suggestion of one of the
older hands, I calculated the voltage divider and confirming that 3.7v was
about as high as I was going to get with that regulator voltage output.  I
put off changing the regulator out, though, because the AGC action is just
about perfect as is.   One day,  when I'm scratching around for something to
do, I may replace it.  I do love this radio.

73,  Jim

Jim Stoneback
K4AXF
Drake SW8
K2.ssb.100.at sn 6194
K2.160.at sn 6263

On 12/13/07, bill KE5KWE <[hidden email]> wrote:

>
> Hello All:
>
> This probably has been asked and answered before but I couldn't find it in
> the archives.  I Set the AGC Threshold and could only get 3.644 volts out
> of
> R1 the potentiometer.  Should I be concerned that I did not get 3.80 volts
> ?
>
> Thanks for the help.
>
> Bill
> KE5KWE
> --
> View this message in context:
> http://www.nabble.com/K2-AGC-THRESHOLD-tp14329860p14329860.html
> Sent from the Elecraft mailing list archive at Nabble.com.
>

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