The Radio Information Board

I'm deployed to Baghdad, Iraq with the US Army, and I work in the commo shop. We've got a bunch of EF Johnson 5100ES radios, model number 242-512A-433JH6, and we need to zero them out before we can turn them in. We don't have any manuals, or programming cables, as these radios were kinda just dumped in our laps.

Is there any way to zero them in stand-alone operation?

Not really. You would need to use their programming software (PCConfigure) and just load a blank template into them.
You can really only zeroize the encryption keys from the radio.