Hi,
I'm retired now and have an interest in electronics. Lately I've turned to radio as an area to explore. It's always been a mystery to me. Digital I've been doing since the seventies
I've think I've now got a good understanding of superhets.
I've got a panasonic portable radio AM/FM as a project to explore. Picked up for less than $10.00. AM does not work, FM is perfect.
I would like to get it going on all cylinders
I have the service sheet and it shows the radio is built around an IC TA8100N. However since most of the action takes place in the IC, I'm having a hard job trying to figure out how to disgnose the problem. The IC has 24 pins at pitch 1.78mm....not socketted, tricky to remove. It may not be the IC that's faulty of course !
Attached schematic..
L1 is the antenna coil. L2 is the oscillator, T3, T4 the IF tfs. I suspect that some of the internal gain on the AM side is damaged within the IC.
All the (AM) voltage readings at the IC pins agree with the service sheet. I have a dual trace scope, but to use it intelligently for this project ??
Is anybody familiar with this IC ? And would care to suggest a strategy to locate the problem - in the interests of my continuing education
I'm retired now and have an interest in electronics. Lately I've turned to radio as an area to explore. It's always been a mystery to me. Digital I've been doing since the seventies
I've think I've now got a good understanding of superhets.
I've got a panasonic portable radio AM/FM as a project to explore. Picked up for less than $10.00. AM does not work, FM is perfect.
I would like to get it going on all cylinders
I have the service sheet and it shows the radio is built around an IC TA8100N. However since most of the action takes place in the IC, I'm having a hard job trying to figure out how to disgnose the problem. The IC has 24 pins at pitch 1.78mm....not socketted, tricky to remove. It may not be the IC that's faulty of course !
Attached schematic..
L1 is the antenna coil. L2 is the oscillator, T3, T4 the IF tfs. I suspect that some of the internal gain on the AM side is damaged within the IC.
All the (AM) voltage readings at the IC pins agree with the service sheet. I have a dual trace scope, but to use it intelligently for this project ??
Is anybody familiar with this IC ? And would care to suggest a strategy to locate the problem - in the interests of my continuing education
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