Hi guys,
Back to this site to ask for assistance, well my neighbor has brought his TEAC AGV8525 that was purchased in the US and was shipped here in Philippines so the input voltage was 120V, he is using a step-down transformer since our line is 220V. Now he is not sure if someone has plug the unit directly to the wall outlet and now the unit does not power on/standby mode. So, what I did is to open the unit, check for any blown fuse. All fuses are good, now check the primary transformer that is located on the main PCB for standby PS and the input is bad, no reading coming from input terminal. Remove the T70 and check and found out on the bottom that there are dark traces, which confirm my theory that this has gone bad. Check output terminals and they are good. So, told him that the primary transformer is toast and we need to replace it, but problem is no parts like that on our electronics shops so it needs to be rewind. I told him to bring it to RAON(Electronics haven
) to have it rewound, explicitly said that output is good so only the primary needs to be rewind to 110V or 120V. Went to work and when I got home transformer is newly rewound, not just the primary but the secondary as well 
So, what I did was test the transformer without load, so tap a 110V to the input terminals, and check using my DMM and I only have 6V on each terminal. (Transformer is a center tap) Now, I am quite confuse since on the schematic diagram that I have downloaded (Attached the Standby PS diag) it said 12 on line. So, in D710 and D711 do the voltage adds up to get the 12V to drive the relay or was the secondary rewound was bad? Do I need to get atleast 12V on each terminal? Thanks for the help.
Back to this site to ask for assistance, well my neighbor has brought his TEAC AGV8525 that was purchased in the US and was shipped here in Philippines so the input voltage was 120V, he is using a step-down transformer since our line is 220V. Now he is not sure if someone has plug the unit directly to the wall outlet and now the unit does not power on/standby mode. So, what I did is to open the unit, check for any blown fuse. All fuses are good, now check the primary transformer that is located on the main PCB for standby PS and the input is bad, no reading coming from input terminal. Remove the T70 and check and found out on the bottom that there are dark traces, which confirm my theory that this has gone bad. Check output terminals and they are good. So, told him that the primary transformer is toast and we need to replace it, but problem is no parts like that on our electronics shops so it needs to be rewind. I told him to bring it to RAON(Electronics haven
) to have it rewound, explicitly said that output is good so only the primary needs to be rewind to 110V or 120V. Went to work and when I got home transformer is newly rewound, not just the primary but the secondary as well So, what I did was test the transformer without load, so tap a 110V to the input terminals, and check using my DMM and I only have 6V on each terminal. (Transformer is a center tap) Now, I am quite confuse since on the schematic diagram that I have downloaded (Attached the Standby PS diag) it said 12 on line. So, in D710 and D711 do the voltage adds up to get the 12V to drive the relay or was the secondary rewound was bad? Do I need to get atleast 12V on each terminal? Thanks for the help.
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