18-11-2012, 10:52 AM
Hi Steve,
I have a Trader sheet for a T100, but that's pretty different. I suspect the basic topology of the circuit is much the same, but all the components are different values.
Old Sparky, this set uses transistors that are quite unusual. They are small white round discs, about 3-4mm in diameter, with wires coming out of 3 sides. They are mounted right down to the PCB. The markings on them don't make immediate sense. These case style is used for the transistors in the IF sections as well. As the encapsulation looks like ceramic, I don't think we are running the risk of tin whiskers here
It's entirely possible that an AF125 would work, but because it's such a pig to work on, I want to be sure before I reassemble it. Just to test it in the set would require about an hour of reassembly, then once working, reinstalling the FM tuner properly and getting the chassis back in the case is probably another 2 hours. It's a total sod!
With the schematics, I'll at least be able to carry out some DC tests before I start reassembly. At the very least, I'd want to check the biasing, etc.
In the past, I've reverse-engineered sections of sets, but even this would be near-impossible as it's all so densely packed.
One thing I now know about Panasonic sets of this era: never again!!!
I have a Trader sheet for a T100, but that's pretty different. I suspect the basic topology of the circuit is much the same, but all the components are different values.
Old Sparky, this set uses transistors that are quite unusual. They are small white round discs, about 3-4mm in diameter, with wires coming out of 3 sides. They are mounted right down to the PCB. The markings on them don't make immediate sense. These case style is used for the transistors in the IF sections as well. As the encapsulation looks like ceramic, I don't think we are running the risk of tin whiskers here
It's entirely possible that an AF125 would work, but because it's such a pig to work on, I want to be sure before I reassemble it. Just to test it in the set would require about an hour of reassembly, then once working, reinstalling the FM tuner properly and getting the chassis back in the case is probably another 2 hours. It's a total sod!
With the schematics, I'll at least be able to carry out some DC tests before I start reassembly. At the very least, I'd want to check the biasing, etc.
In the past, I've reverse-engineered sections of sets, but even this would be near-impossible as it's all so densely packed.
One thing I now know about Panasonic sets of this era: never again!!!
