[Heathkit] Modern VFO

[k2cby]

I was lucky enough to get one of the NorCal direct synthesis digital VFO
kits while they were still selling them several years ago. I have used it
with great success to drive a Viking I AM-CW rig, and I am now planning to
use it with my Heathkit SB-301/SB-401 combination on SSB.

 

The great advantage of that particular kit is that you can program the
display for almost any conversion scheme (HFO-VFO, HFO+VFO, VFO-HFO, VFO x
2, VFO x 3, VFO x 4, etc.). The other benefit is that you can program a
different conversion scheme for each band, with a couple of spare channels.

 

As Ed, K9EW, pointed out the display does not show the transmitted frequency
but a mathematical function of the VFO output.

 

The down-side to this and most other synthesized VFOs is that they don't
have enough oomph to drive a tube transmitter, although this can be cured by
adding a post-amplifier.

 

While the NorCal kit is no longer available, there are others on the market.
Jim Haggerty, (WA1FFL.COM) sells one - and also published the circuit for a
driver amp (which he also sells) in June 2011 CQ. EBay also shows several
for sale from the Far East.

 

 

Miles B. Anderson, K2CBY
16 Round Pond Lane
Sag Harbor, NY 11963
Tel.: (631) 725-4400

Fax.: (631) 725-2223
e-mail: k2cby at optonline.net