I like these Zetron controllers for my repeaters. Although they stopped being made many years ago, They are available in the used market and usually at a fair price.
Here are some tips and information I put together from my latest project.
This one is the Zetron 38a
I have had these same controllers with different names on the front including Johnson and Kenwood, but they all seem to be Zetron on the inside.
I program these on the workbench using a pair of Motorola mobile radios to get the controller close to where I need it and to test it out.
Programming is easily done from the front panel of the controller using a laptop computer running a program like Putty.
Here are some screenshots:
Also, Thanks to Repeaterbuilder for a lot of the information about controllers and Motorola radios.
More to follow.
Zetron 39 on the Analog MSF5000 UHF Repeater.