[Collins] SYNTHESIZER FOR DRAKE RECEIVER BY HAGEMAN

[Dr. Gerald N. Johnson]

On Sat, 2006-10-14 at 10:05 -0400, kiyoinc at attglobal.net wrote:
> I was mulling this over:
> 
> > SYNTHESIZER FOR DRAKE RECEIVER BY HAGEMAN (MINI KIT)
> > 
> > QST Jun04
> > 
> > Description: This project allows the R4 receiver to tune a 0.5 MHZ
> > frequency range from 1.5 to 30 MHz with an LCD display. The mini kit
> > consists of the programmed PIC, PC Board, (2) 7805 regulators, the
> > MC145170d2 IC, op27gz opamp IC, and Mini Circuit 100 MHz VCO. The
> > mini kit includes all the hard to get parts. Please specify the R-4
> > OR SPR-4.. See www.arrl.org/files/sqtbinaries/drake_synth_zip
> 
> 
> From: http://www.farcircuits.net/vfo2.htm#6vfo
> 
> Seems to me that a similar synthesizer but programmed for 200 kHz steps, 
> and the Collins PTO offset/IF, would turn an S-Line into a fully agile, 
> all-band rig.  Kinda like a 51S-1.
> 
> I've been looking for a complete kit of parts but haven't found one.
> 
> de ah6gi/4
> 
While its not as convenient for band scanning, the S-line with an easily
accessed crystal socket and a crystal pack works that way, quite well.

The synthesizer tends to have a lot more phase noise than the crystal
oscillator and so degrades receiver performance when strong signals are
near the desired weak signals.

There has been a commercial synthesizer for S-line. Cost last I recall
was on the order of $750. Its not as simple as the one for the Drake
because Collins crystal frequencies all end in 55 KHz where the drakes
end in 00 KHz.
-- 
73, Jerry, K0CQ, Technical Advisor to the CRA
All content copyright Dr. Gerald N. Johnson, electrical engineer