[NLRS] 10368 transverter

[Andrew T. Flowers, K0SM]

Here's another cheap signal generator idea:

I found by accident that many brick oscillators will lock at 1/2 of 
their designed frequency.  I've been using the AM-QRP 0-60 MHz DDS-60 
synthesizer to lock bricks that take a 100-mhz range input.  I've 
accomplished this with M/A-COM, Micromega, and CTI bricks.   This means 
you can pretty much tune anything within the output filter of the brick 
by driving it with a subharmonic.  For example, setting my DDS-60 to 
output 48 MHz will lock a brick just as if you were dumping in 96 MHz, 
and it's tunable.  I don't know what phase noise and other stuff looks 
like, but it certainly will generate signals where you want them.  I've 
modified board to take an input from an OCXO for added stability.  Here 
are the details on the kit.

http://www.amqrp.org/kits/dds60/

So, with a little math and some brick oscillators you can come up with 
sources for all kinds of things--I might get around to writing this up 
for Central States if I find the time...

Andy, K0SM/2



Dr. Gerald N. Johnson wrote:

>On Thu, 2006-02-16 at 15:42 -0600, BRISCH at qwest.net wrote:
>  
>
>>Good day everyone, on a fact finding mission.
>>I have been studying the schematic for the DEM transverter.
>>A rumor has it that the transverter can be converted into
>>a signal generator.  Has anyone here done it? 
>>The folks at DEM are out again so I can't ask them
>>until they get back.
>>The way I see it is to change the LO so it does not have an offset
>>and use it as a signal source.  No IF rig involved,
>>directly coupling the LO output through the final circuits
>>to provide a signal. Sounds good in theory but what are the
>>gotchas?  Would like to get everyone's thoughts on this.
>>
>>Bill K0QK
>>    
>>
>
>Or drive the transverter input with an IF frequency signal generator.
>The transverter being linear over some fair dynamic range should allow
>varying the 10 GHZ output signal with the IF signal generator attenuator
>limited by the maximum output of the transverter and the noise output of
>the transverter on the low end.
>
>Otherwise the LO can serve as a signal generator but it doesn't have
>much frequency agility or built in attenuation. It needs a different
>crystal, probably one on 96 MHz.
>
>  
>




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