[NLRS] 10368 transverter

[Doug Reed]

Jerry's suggestion about using a RF signal generator into the 
transverter as your signal source is obviously the best option, 
particularly if you happen to have one.... Just put the transverter into 
TX mode and plug the sig gen into the IF radio port. An advantage of 
this option is that you can explore the frequency limits of the 
transverter, not just within the frequency range of the IF radio.

If you put an RF attenuator after your IF radio you can do the same 
thing using it as the signal source in CW mode. Just watch the power 
dissipation of the attenuator. You should probably put a 6dB or 10dB pad 
ahead of the variable attenuator, just to be safe. If you don't have a 
good fixed pad, try 100-200 feet of cheap RG-58 coax.....

If you don't have a good variable attenuator to use, you can get some of 
the benefit of variable signal level by connecting a 1 KHz sinewave 
audio signal generator into the mike input while in SSB mode and running 
that signal up and down. But don't expect more than 30-40dB of signal 
level difference because there is some amount of carrier and sideband 
leakage.

I suggest using a 200:1 resistor attenuator at the mike input so the 
audio generator can run in its normal 0-10 volt range. Use 100 ohms 
across the mike input and 10K to 50K in series to the generator. This 
will help eliminate hum and noise from the audio leads but will NOT 
eliminate ground loops.

Combining the audio generator and fixed or variable RF attenuators would 
allow you to cover a fairly wide range of signal levels, within the 
limits Jerry mentioned.

I expect that one of these ideas is what DEM had in mind.

73, Doug Reed, N0NAS.

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
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