An old 1976 Midland 13-862C 23 channel CB. I replaced the 11.275 MHz transmit crystal with a 10.240 MHz crystal removed from a newer 40 channel CB. After adjusting the pots I was able to get the radio to transmit 1 watt solid peaking at 1.5 watts.
The keyer is a homebrew microcontroller based keyer. It is a little overkill, but it works great for this application. The chip is an ATMEL ATMega8. It is has an 8Mhz processor, 1Kbytes of SRAM, 512 bytes of EEPROM, and 8Kbytes of in-system programmable flash memory. I programmed it from the ground up using pure ASSEMBLY language. This keyer needs little external parts, and is very low current. See schematic below.
Check out the datasheet for this chip doc2486.pdf < big download 5.1Mb
http://www.atmel.com ATMEL the manufacturer of this chip.
I ran this beacon for 6 months straight and received confirmation that my beacon was heard in the following states (green).
CLICK HERE for my other beacon project with a Midland 13-892