I have never had a Siltronics VFO, but I did run some of the PAL VFO`s Back in the day.
There were several different models and each one basically replaced one crystal in the radio and allowed you to put your radio on one channel and then use the VFO to move around across a large frequency range.
Different Models would output different frequency's to match what ever the mixer scheme was used in each radio.
Have a look at this page.
http://www.firestik.com/Instl-Art/vfo-sheet.gif
That shows the ones that were made by Firestick ( back then it was PAL), see how there are different models to fit different radios.
Now, I do not know if the Siltronics was made JUST for the Siltronics radio`s, if they made different models, or if you can swap a crystal inside the unit, and re-tune for a different output frequency.
Hopefully some one that is more familiar with that VFO that can asnwr these questions.
( on Edit You can go to that main page http://www.firestik.com/Tech_Docs/Pal_Menu.htm
Scroll down to the PAL VFO/VCO section and see how they were installed and some more info for reading)
73
Jeff
