[VHFcontesting] 222 and 902/3 transverters

[Michael Sapp]

Hi Folks: For anyone considering building their own 222 and 902/3 MHz 
transverters as an alternative to buying a kit or ready made transverter 
consider this LO scheme.  If you use a 170MHz LO on 222MHz with a 52MHz IF 
(170+52= 222) , it can also be used as a common LO for 902/903. The 170Mhz 
x5 is 850Mhz + 52 Mhz = 902. With radios like the ft-817 so popular as 
transverter drivers using the 6 meter IF is not a problem, and the 52 or 53 
Mhz (903) IFs will be far enough away from 50.125 MHz so as to not be a 
conflict in a multi-op contest situation. You could even use common MMICs in 
the TX/RX amplifier chains and swap BPFs with PIN diodes or small relays. 
Henry Radio has also been selling some low cost ($10~20)  broadband 
amplifier modules on ebay to get into the 1~3 watt range, so it's not like 
you have to fork out $60~$90 for final TX amplifiers.

Since the 222 and 902/3 MHz bands have always been "odd man out" as far as 
commercial radios one would think a two-for-one transverter would be an 
attractive option for many VHF/UHF ops.  I'm surprised no one has taken 
advantage of this option as I have yet to see something like this show up in 
ham radio literature. Mike WA3TTS