[GreenKeys] Looking for VFO (1.5-2.0 Mc range) with FSK

[WA5CAB at cs.com]

Russ,

I agree with Roy.  I'm puzzled as to why you want the VFO to cover 1.5-2.0 
MC.  Doubled that covers 3.0-4.0.  But tripled it covers 4.5-6.0.  Leaving a 
gap.  If the original design used a VFO on half the lowest output 
frequency, the VFO probably covered 1.5-3.0.  

However, regardless of that, it is unlikely that the input to the first 
stage doubler (if such it is) in the transmitter is itself tuned.  Usually only 
the outputs of multiplier stages are tuned.  In which case if the 
transmitter would operate on an output of 3.0-6.0 with an input of 1.5-3.0, it will 
also operate with an input of 3.0-6.0.  The TCS is like that.  It's basic 
range happens to be 1.5-3.0, and all of its crystals are in that range.  But it 
operates just fine on 3885 KC with a 3885 KC crystal plugged in.  A few 
weeks ago, I proved it with a crystal blank transplanted from a DC-35 holder 
into one of the rare TCS crystal holders that take 3/4" square crystal blanks 
(most take 1" blanks, but that isn't pertinent to the current discussion).

If you must have 1.5-3.0 MC input, my only suggestion is a TCS transmitter. 
 But if what I wrote above is correct, you could use a 2.0-4.0 MC BC-221 
(or LM).  If a BC-221 will work, I have one that decades ago I transplanted to 
a 19" rack panel that I would sell for not much.  That might put you on 80 
Meters RATT.  Or I probably have some unrestorable TCS transmitters, too.  
But you would have to provide the power supply and the FSK keyer circuit.

In a message dated 10/14/2009 10:36:43 PM Central Daylight Time, 
k1lky at earthlink.net writes: 
> On Oct 14, 2009, at 3:07 PM, wa3frp at aol.com wrote:
> 
> >
> >Hi Guys,
> >
> >Turning to Greenkeys for ideas. My vintage (1959) TX is designed to  
> >operate 3 to 30 Mc but is mainly crystal operated. The current VFO  
> >will run the TX on 40M and up.
> >
> >But I would like to work some 80M RTTY this winter since the  
> >sunspots are still low.
> ...
> >What I would like to find is a VFO with an output that covers 1.5 to  
> >2 Mc.
> 
> Russ,
> 
> If you can find a Northern Radio Company Type 105  F.S. Keyer, it  
> would do well for you. However, it's normal output is from 2 to 4 mc,  
> and it multiplies up to 32 mc, i am pretty sure.  I seem to remember  
> noticing that they will tune from about 1.8 mc up. Just why  you need  
> 1.5 mc is not clear to me.
> 
> To be frequency agile, then need an external oscillator, from 2 to 4  
> mc.  They have space for three crystals for fixed frequency operation.
> 
> In 2005, I emailed with  fellow in CA who had two of the Type 105's  
> (and needed a manual). His email then was   
> boatanchor at martasystems.com  and he was on this list.  I have no idea  
> if he'd let one of his go.  But be advised these things are HEAVY, and  
> they need a separate power supply.
> 
> TMC also made an rf-output FSK keyer.  They are harder to find, though.
> 
> Roy
> 
> 

Robert & Susan Downs - Houston
wa5cab dot com (Web Store)
MVPA 9480