I know this is an old topic, but I've tried many of the old ideas with no luck. This is a 10 pin transformer from an old Magnavox color tv and I'm wondering if there is something wrong with it because my readings seem odd.
First, I tried to find the 0V pin on the secondary by running 15V DC through the HV red wire and checking each pin for voltage. I found 0.54V on pins 2,3,5,6,& 9. A quick continuity check showed continuity between all of these pins and each other. This confused me at the start, because I expected to only find 1 pin for the 0V on the secondary so I don't know what to make of this. I tried reversing the polarity of the DC source and got no voltage that way so the polarity seemed correct.
Secondly, I looked for the primary by measuring the resistance between all of the various pin combinations and found 12 combinations with resistance between 0.8-1.3 ohm. I had read that the primary pins are usually adjacent, the only ones meeting that criteria were pins 5-6 which had 0.7 ohm (but both of those seemed to be associated with the secondary circuit...possibly). Several other combos had resistances around .5 or less.
Since I didn't know what to make of all this I thought I would try the brute force approach. I have an 11 volt AC source, so I ran that through every possible combination of pins that had shown resistance or continuity, and checked for any output from the red HV wire with each unoccupied pin as a possible 0V pin. From this I got about 16 combinations that produced an AC output, but none that were over 2 volts. This also confused me because I had expected a significantly higher voltage from at least one of these.
This is the first flyback transformer I've tried to salvage, so I'm either missing something glaringly obvious to everyone, or I got a very strange/bad one here. The transformer itself is from Mexico, I googled all the numbers on it and found some documents in Spanish but they weren't very useful (I don't even know if they were about anything electronic). It also has a thick white wire coming from the top attached to focus/screen controls and a thinner white wire coming from the base ending in a single connector.
Any suggestions appreciated. I just have my multimeter, 11V AC, and 0-15V DC sources for testing purposes.
Richard
First, I tried to find the 0V pin on the secondary by running 15V DC through the HV red wire and checking each pin for voltage. I found 0.54V on pins 2,3,5,6,& 9. A quick continuity check showed continuity between all of these pins and each other. This confused me at the start, because I expected to only find 1 pin for the 0V on the secondary so I don't know what to make of this. I tried reversing the polarity of the DC source and got no voltage that way so the polarity seemed correct.
Secondly, I looked for the primary by measuring the resistance between all of the various pin combinations and found 12 combinations with resistance between 0.8-1.3 ohm. I had read that the primary pins are usually adjacent, the only ones meeting that criteria were pins 5-6 which had 0.7 ohm (but both of those seemed to be associated with the secondary circuit...possibly). Several other combos had resistances around .5 or less.
Since I didn't know what to make of all this I thought I would try the brute force approach. I have an 11 volt AC source, so I ran that through every possible combination of pins that had shown resistance or continuity, and checked for any output from the red HV wire with each unoccupied pin as a possible 0V pin. From this I got about 16 combinations that produced an AC output, but none that were over 2 volts. This also confused me because I had expected a significantly higher voltage from at least one of these.
This is the first flyback transformer I've tried to salvage, so I'm either missing something glaringly obvious to everyone, or I got a very strange/bad one here. The transformer itself is from Mexico, I googled all the numbers on it and found some documents in Spanish but they weren't very useful (I don't even know if they were about anything electronic). It also has a thick white wire coming from the top attached to focus/screen controls and a thinner white wire coming from the base ending in a single connector.
Any suggestions appreciated. I just have my multimeter, 11V AC, and 0-15V DC sources for testing purposes.
Richard