I made another trip to Eggardon Hill today and replaced the broken Tiny2 with a KPC3 TNC. All seem to be working as it should again.
The TNC is at an angle because the power lead was not long enough. When I made the leads up for the radio to TNC link many years ago, I put an adaptor in the lead so that I could use it with both makes of TNC. I am rather glad I did!