John and John: Thanks for your remarks. I have been in touch with Steve KD1JV, and he said the code was not his but was added by 4SQRP. In fact it was written by Dan Tayloe. Another ham whose opinion I respect said that as far as he knew, the code was never released.
I received this Tenna Dipper from a ham who built it but had no luck in getting even a tiny spark of life. It was completely dead. So I bought it for the price of mailing and took it on as an exercise in troubleshooting. Even though I haven't had 100% success, it's been a gratifying project. I appreciate knowing that it may yet be functional.
4SQRP no. 261