The 13TxCtrlr is a controller for the well-known ComTech 13cm transmitters using a pic16f84 microcontroller.
The frequency is adjustable in 500 kHz steps using a Bourns rotary-encoder. The transmitter can be switched on and off with 2 push-buttons.
The startup-frequency can be saved by pushing either the on- or the off-button a second time.
A 2x16 LC-Display shows the frequency and status (On/Off) of the transmitter as well as your own callsign.
You can change this callsign using the included program ChangeCall.exe.
The controller can be put in a test-mode by pushing and holding the off-button while powering the unit.
While in test-mode the ComTech-transmitter does not need to be attached and a letter T is displayed in the LCD.
While you pushing the power-button and rotate the rotary-encoder, it's possible to change the outputpower. 
The print also has the connectors for video, 2x audio and Nicam inputs.
If you want to use 7.02 and 7.20 for the audio-carriers and/or if you want to use Nicam you have to modify the Comtech-transmitter. For adjustable outputpower, you have to modify the comtech-transmitter.(foto comtech module) 
David PE1MUD has published a modification for Nicam in the Repeater magazine. Click here for a description of this modification.
G1MFG has a site with various modifications for the ComTech transmitters and receivers. One of them is for increasing the level of the audio-carriers.
A modification for changing the audio-carriers frequency to 7.02 and 7.20 MHz will follow.

What do you need to build the controller ?