[TenTec] Model 260 PSU factory modifications

[Steve Hunt]

I recently bought a spare Model 260 PSU. Checking it out, on the 
regulator board I found a missing diode, and an extra diode, resistor 
and PNP transistor tacked at the rear of the PCB.

At first I thought the previous owner had made the changes, but I 
checked my other 260 and it's the same. The schematic in the manual does 
not reflect these changes.

I wonder if anyone knows the reason for the modifications, or if anyone 
has a later schematic that shows the changes?

Steve G3TXQ