Transformer pin out on a radio receiver

Thread Starter

Klaidas Stumbras

Joined Jul 7, 2016
19
Hello i need help to figure voltages on these wires coming from transformer.The transformer stopped working after rain and thunder then i opened the radio (seen in the picture below) and checked the transformer and i figured that the main HV side of transformer has no continuity when checked with multimeter however the low side of the transformer has continuity.
Yellow and Blue wires have = 31,5 ohm
Yellow and Red wires have = 31,5 ohm
Yellow and Black wires have = 26,3 ohm
Red and Black wires have = 6 ohm
Red and Blue wires have = 11,2 ohm
Black and Blue wires have = 6 ohm

Seem odd that all of the wires are connected together ... i dont know maybe all the coils are blown ? HELP
 

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SLK001

Joined Nov 29, 2011
1,549
Seem odd that all of the wires are connected together ... i dont know maybe all the coils are blown ? HELP
I doubt it. Plug in the primary side and measure the voltages on the secondary windings. The inside of the radio doesn't look wet, so it could be something else.
 

MaxHeadRoom

Joined Jul 18, 2013
28,700
Those transformers have a small thermal fuse embedded in the winding, in some cases you can see the ends poking out and short them across, this has to be confirmed with a resistance check to the pri winding.
You could then fuse the primary externally with a tight value.
Max.
 

MaxHeadRoom

Joined Jul 18, 2013
28,700
If you are lucky enough, you will see two very small tabs sticking out of the primary winding with a wire connected to each, you may have to expose part of the coil bobbin to see it.
Some are embedded deep, unfortunately it is a one-time fuse, it saves the transformer from burning out, but makes it useless in the process.
Max.
 
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