RE: Orbit Radio
Hello Orbit Radio fans, I just got done refurbishing/updating an old Orbit 4/8 system and was wondering if anyone still had copies of the factory schematics (available back in the day for $1.95 as per the owner's manual). It was kind of a pain without the schematics so I just hand drew the important circuits from the board (you can actually see the discreet components and work on the board without a $10,000.00 Pace vacuum reflow setup!!) The only parts I had to replace were a few dried up 'lytic caps here and there and replaced them with tantalums, and of course the batteries (upgraded to NiMH). I narrowbanded the Tx with a Fred Marks 'Miller Integration' circuit from an old ACE radio and 2 or 3 well placed caps in the encoder. I narrowbanded the Rx with a 455 kHz ceramic filter in the first I.F. stage gain circuit from an old Kraft radio. The servos just needed cleaned/lubed and I recentered everything to modern day 1.5 ms. neutral. The only real pain was the Rx crystal because it is a 5th overtone type unlike any other AM r/c crystal I could find so I had to have one custom cut. If anyone has or knows of an Orbit schematic package please let me know!!