[Elecraft] K1 no output on 20m

Sun Aug 3 16:38:00 2003

On the other hand...

If I'm getting no output AND no receive on 20m, it has to be the filter board. That's the first common point between the T-R switch and the mixer, correct?

Arrrgh ;-).

John Pfeifer - KLØWN
Kodiak, Alaska

>Date: Sun, 03 Aug 2003 12:25:00 -0800
>To: [email protected]
>From: John Pfeifer - KLØWN <[email protected]>
>Subject: Re: [Elecraft] K1 no output on 20m
>
>Hello again,
>
>After posting my initial message, I decided to do some "Cheap 'N Dirty"=
 signal tracing as described by Tom Hammond(NØSS).
>
>I have a KFL1-4 filter board set up for 40m, 30m, 20m & 17m.
>
>I used a 15ft length of wire with a 550pF blocking capacitor.
>
>At test point #1 (RF Board, T1-1, input winding of the transformer feeding=
 the mixer), I got clearly discernable signals on 40m, 30m & 17m.  No change detected at all on 20m.
>
>I tried a few more test points for all bands and--once again--signals were=
 present on all bands except 20m.
>
>On the chance 20m was totally dead, I even hooked up my Wilderness SST to a=
 dummy load (1 watt) and used it as a poor-man's signal generator.  Wrapped the "signal probe" wire around the dummy load and tuned around a bit with the K1 while holding the test probe on T1-1, lead 1. Couldn't find a signal anywhere.
>
>If no signal is present at T1-1, lead 1, the problem must be downstream of=
 the filter board.  But how come 20m is the only band that doesn't work.  Seems like if there's a problem at input of the receive mixer, all four bands would be dead...
>
>Any ideas?
>
>BTW, my K1 is serial #1456 and it has the newer, blue trimmers.
>
>Thanks!
>
>John Pfeifer - KLØWN
>Kodiak, Alaska
>
>At 11:58 AM 8/3/2003 -0600, Rod N0RC wrote:
>>John,
>>
>>Do you have a 2 or 4 band K1? Is 20m the only band affected?
>>
>>First. double check all of your toroids. Are they tinned and soldered in
>>properly. As Gary from tech service has said, PTTL are often the cause.
>>(PTTL = poorly tinned toroid leads)
>>
>>Next thing to are check trimmer caps, if you have a 4 bander. If you
>>have a 4 band K1 does it have the older white trimmers or the new blue
>>ones? If older white ones, give the trimmers associated with 20m (and/or
>>other affected bands) a few complete turns, 5-10. Some foreign matter
>>(oxide, dust...) may have worked its way into the trimmer(s).
>>
>>Also, recently, I worked on a 4 band K1 with older white trimmers,
>>output was down on some band. I noticed some of the trimmer caps were
>>loose, very easy to turn. I suspected vibration from transporting the
>>unit might have caused them to move a tiny bit.
>>
>>73, Rod N0RC
>>
>>
>>----- Original Message ----- 
>>From: "John Pfeifer - KLØWN" <[email protected]>
>>To: <[email protected]>
>>Sent: Sunday, August 03, 2003 11:33 AM
>>Subject: [Elecraft] K1 no output on 20m
>>
>>
>>Hello all,
>>
>>My K1 was behaving normally until yesterday.  As I was trying to tune
>>the rig up on a 1/4-wave 20m vertical, the KAT1 relays clicked endlessly
>>and I saw the following: