902 Orion RX

A long time ago I wanted to make a 33cm Ham repeater using nothing but Orion radios… the 900Mhz Orion will TX in 927 just fine but I was told no Orion will RX in 902… so I decided to try and modify the 800Mhz Orion to RX in 902Mhz because I wanted an all-Orion repeater…

I honestly can’t remember much of what I did seeing as this was 6~7 years ago but it all began with some trial and error (mostly error)

Playing with caps till I managed to get the VCO Line to 5v…

Success!

Obviously this isn’t an ideal part but it did the job… solder in place…

Result…

Finally ended up integrating it into a little /\/\otorola desktop repeater cabinet with a home-made dual radio cable that also goes to a DB-25 to interface with a CAT-2oo repeater controller (not pictured was used later in another repeater) along with a 900Mhz Orion for TX along with a small power supply and a mobile duplexer… the 800Mhz PA was removed to save a bit of weight… used the flex ribbon from the PA for it’s DB37 interface and a coax pigtail from an MTX or something like that can’t remember…

800Mhz Orion RX’ing 902Mhz

Since it was setup in a dual-radio config if you TX in Talk Around the 900Mhz Orion will show RX’ing

Home-Made Dual Radio cable along with the DB-25 connector for going to the CAT-200 Repeater Controller (missing)

Two things that are not really mentioned is you must remove/replace (or in my case just bypass) the filter on the RX side or the radio will be incredibly deaf… bypassing the filter the radio is about -118 ~ -120 or so which is not bad… additionally if you do use a disk cap (ideally you would use a proper cap) you need to glue it down with some hot glue or something if not the radio will be incredibly micro phonic…