K1 - Building - VFO range

[Joseph M. Durnal]

Back when I was building the filter board there were some steps
required for selecting the VFO range, but it only seemed to apply to
30 metes.  My kit will be for 40 & 15 meters, and I'm thinking that I
won't need any more than 80 kHz so I'm thinking I will just use the 68
pF capacitor for the VFO.  Any final suggestions before I heat up the
soldering iron?

Time to go wind 33 turns around the T50-6 toroid core!

Thanks & 73 de Joseph Durnal NE3R
_______________________________________________
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

[crstrode]

 Joseph,

I finished my K1 a few weeks ago, and I'm still tinkering with it.

I installed the default capacitor for the 80 KHz VFO tuning range - and I'm glad I did!

In my particular instance, I ended up with about 100KHz of range.  I was actually thinking of installing a different value to reduce the range somewhat.  The advantage to this is less KHz per rotation of the tuning knob.  I'm used to the K2, and other radios that have a much slower tuning rate.  Many others have commented previously that the extended tuning range has benefits that outweigh the fast tuning that comes from a 150KHz range.  I don't disagree with them, however, since most of the action takes place in a narrow (and getting narrower!) range, I believe that 80 KHz is more than adequate.

FYI - When building was finished the K1 tuned from about 6.800 to 7.080 on 40 meters.  The other bands were similar in the tuning range below the bottom band edges.

This was fine with me, but I changed it anyway to do away with the out of band coverage at the bottom end.  This was a simple matter of squeezing the turns together a bit on the big yellow VFO inductor.  I didn't even need to remove the nylon bolt and washer.  Just nudge the windings a bit and check the tuning range.  Tweak as needed to end up with a slightly higher bottom end tuning range value.  WORKED GREAT!

I would suggest that you just do what the manual says and see how it works for a few weeks before any additional adjustments or mods are made.


Carl Strode
WA7CS
_______________________________________________
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

[crstrode]

Please excuse the typo!

Range should be 6.980 7.080

Geez!

Carl
WA7CS

-----Original Message-----



FYI - When building was finished the K1 tuned from about 6.800 to 7.080 on 40 meters.  The other bands were similar in the tuning range below the bottom band edges.
_______________________________________________
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

[Joseph M. Durnal]

Thanks again Carl.  You won't find much CW above 7080 these days.  I
haven't been on HF long enough to know what 15 meters will be like in
a few years, but I expect that most activity will be between 21000 and
21080 kHz.  If I get a few extra kHz of bandwidth, that is great too.
I have a busy day today, but I hope to have a working receiver by the
end of the day!

73 de Joseph Durnal NE3R
_______________________________________________
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