K2 #4970 is now a K2/100

[John E. Reiser]

Hi everyone,

Last night, I finished building and testing the KPA100.  Today, I made several QRO contacts and got good reports on the audio from the KSB2 and the Heil desk mike.

K2 # 4970 also has the noise blanker, DSP filter and 160 meters installed.  The DSP filter is incredible.  Signals seem to just pop out of a nearly quiet background when it's on.  I love this radio.  It's better than my 756 pro II.

The only odd things I encountered while testing the amp were:

1) on 160 M the current draw is about 27-28 amps at 100 W out, all other bands are 20 amps or less;

2) maximum attainable output on 30 meters is 68 watts; all other bands reach 100 watts + except 10 meters, which reaches about 90 watts.

Other than this, the radio and all its options are working perfectly.

What I am wondering about is whether or not the amp is working normally.  Has anyone had the same experience

Thanks and 73,

John, W2GW
_______________________________________________
Elecraft mailing list
Post to: [hidden email]
You must be a subscriber to post to the list.
Subscriber Info (Addr. Change, sub, unsub etc.):
 http://mailman.qth.net/mailman/listinfo/elecraft   

Help: http://mailman.qth.net/subscribers.htm
Elecraft web page: http://www.elecraft.com

[Don Wilhelm-3]

John,

The 30 meter low power can be cured by replacing C80 and C81 in the KPA100 -
go the the Elecraft website Builders Resource page and look at Builders
Alert #22 - yes, I know it says 20 and 17 meters, but it applies sometimes
to 30 meters as well.

You may have to replace the 1.6 ohm 2 watt resistors if you still have
problems after replacing the capacitors.  Apparently the resistor
characteristics from the manufacturer have changed from batch to batch.

Your 160 meter high current draw might be helped by re-tuning the 160/80
meter bandpass filter to favor 160 meters more than 80 meters.  This filter
is quite broad and serves both bands with the fixed capacitors.  If you feel
a need to 'tweak' the filter so that it peaks on both bands, you can try
adding some padding capacitors in the appropriate places in the filter.  I
can't tell you which ones to pad without knowing the entire filter tuning
peaks.

73,
Don W3FPR

> -----Original Message-----
>
> Last night, I finished building and testing the KPA100.  Today, I
> made several QRO contacts and got good reports on the audio from
> the KSB2 and the Heil desk mike.
>
> K2 # 4970 also has the noise blanker, DSP filter and 160 meters
> installed.  The DSP filter is incredible.  Signals seem to just
> pop out of a nearly quiet background when it's on.  I love this
> radio.  It's better than my 756 pro II.
>
> The only odd things I encountered while testing the amp were:
>
> 1) on 160 M the current draw is about 27-28 amps at 100 W out,
> all other bands are 20 amps or less;
>
> 2) maximum attainable output on 30 meters is 68 watts; all other
> bands reach 100 watts + except 10 meters, which reaches about 90 watts.
>
> Other than this, the radio and all its options are working perfectly.
>
> What I am wondering about is whether or not the amp is working
> normally.  Has anyone had the same experience
>
> Thanks and 73,
>
> John, W2GW
>

--
No virus found in this outgoing message.
Checked by AVG Anti-Virus.
Version: 7.0.323 / Virus Database: 267.9.0/50 - Release Date: 7/16/2005

_______________________________________________
Elecraft mailing list
Post to: [hidden email]
You must be a subscriber to post to the list.
Subscriber Info (Addr. Change, sub, unsub etc.):
 http://mailman.qth.net/mailman/listinfo/elecraft   

Help: http://mailman.qth.net/subscribers.htm
Elecraft web page: http://www.elecraft.com

[Fraser Robertson]

John, our club's K2/100 does the same thing - high current on topband, but
it seems normal on all other bands.  I mentioned it on here some months
back, and received some useful suggestions to try, but I never did find
anything wrong as such, or a cure for that matter.

73 Fraser G4BJM

>From: John Reiser <[hidden email]>
>To: [hidden email]
>Subject: [Elecraft] K2 #4970 is now a K2/100
>Date: Sun, 17 Jul 2005 12:55:57 -0400
>
>Hi everyone,
>
>Last night, I finished building and testing the KPA100.  Today, I made
>several QRO contacts and got good reports on the audio from the KSB2 and
>the Heil desk mike.
>
>K2 # 4970 also has the noise blanker, DSP filter and 160 meters installed.  
>The DSP filter is incredible.  Signals seem to just pop out of a nearly
>quiet background when it's on.  I love this radio.  It's better than my 756
>pro II.
>
>The only odd things I encountered while testing the amp were:
>
>1) on 160 M the current draw is about 27-28 amps at 100 W out, all other
>bands are 20 amps or less;
>
>2) maximum attainable output on 30 meters is 68 watts; all other bands
>reach 100 watts + except 10 meters, which reaches about 90 watts.
>
>Other than this, the radio and all its options are working perfectly.
>
>What I am wondering about is whether or not the amp is working normally.  
>Has anyone had the same experience
>
>Thanks and 73,
>
>John, W2GW

_________________________________________________________________
It's fast, it's easy and it's free. Get MSN Messenger 7.0 today!
http://messenger.msn.co.uk

_______________________________________________
Elecraft mailing list
Post to: [hidden email]
You must be a subscriber to post to the list.
Subscriber Info (Addr. Change, sub, unsub etc.):
 http://mailman.qth.net/mailman/listinfo/elecraft   

Help: http://mailman.qth.net/subscribers.htm
Elecraft web page: http://www.elecraft.com