A couple of months ago I purchased a Magnavox record player model number 1ST627A. It worked fine for a couple of weeks and then without warning this horrible humming started coming out of the speakers. A friend of mine helped me take the back off and we saw that the tubes were all still glowing but there was a burning smell. So, we immediately unplugged it and looked for the source. Upon unbolting the amp and lifting it up we saw that the power transformer was pretty much fried. I would like to replace just that part if at all possible but am unsure of the specs and what to buy.
Thanks!!!
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
Thanks!!!
Welcome!
One thing is you should correct the reason why the PS trans overheated and failed in that amp. It should have been recapped before use, unless it was and you got a bad PS cap.
Caps maybe have life of 20yrs, and after that they can short out or go open circuit get weak etc. Coupling caps to the output tubes and in preamp section also. Bad coupling caps can take out Output Transformers & Tubes also.
If it doesn't have a fuse it's wise to add one before the PS transformers also.
You can leave the can cap(s) for looks and unhook, just wiring replacement caps under chassis. Less $ also that way.
Good idea to also clean the tube sockets, tube pins, pots, & switches.
While your at it check the resistors (with the tubes out) to see if any drifted way off. It will be noticeable even in circuit.
It's wise to take lots of detailed pics beforehand and only replace a part or two at a time to make sure you got it right.
Don't run it without a load even when testing as you risk the Output Transformers. You can use 16 ohm 25W+ resitors for a load.
Your pics aren't showing up. Heyboer in MI can rewind yours. or make a replacement also. Edcor might make something close.
Be carefull of HI Voltage and make sure caps are discharged before working on it. If you have to check voltages powered on Clamp on clips are safer to work with then probes. Keep one hand behind your back so your heart isn't in the circuit.
There are lots of rebuilds at AK (audiokarma) also.
Maybe like this model?
http://www.shedradios.com/MAG1ST606.HTML
One thing is you should correct the reason why the PS trans overheated and failed in that amp. It should have been recapped before use, unless it was and you got a bad PS cap.
Caps maybe have life of 20yrs, and after that they can short out or go open circuit get weak etc. Coupling caps to the output tubes and in preamp section also. Bad coupling caps can take out Output Transformers & Tubes also.
If it doesn't have a fuse it's wise to add one before the PS transformers also.
You can leave the can cap(s) for looks and unhook, just wiring replacement caps under chassis. Less $ also that way.
Good idea to also clean the tube sockets, tube pins, pots, & switches.
While your at it check the resistors (with the tubes out) to see if any drifted way off. It will be noticeable even in circuit.
It's wise to take lots of detailed pics beforehand and only replace a part or two at a time to make sure you got it right.
Don't run it without a load even when testing as you risk the Output Transformers. You can use 16 ohm 25W+ resitors for a load.
Your pics aren't showing up. Heyboer in MI can rewind yours. or make a replacement also. Edcor might make something close.
Be carefull of HI Voltage and make sure caps are discharged before working on it. If you have to check voltages powered on Clamp on clips are safer to work with then probes. Keep one hand behind your back so your heart isn't in the circuit.
There are lots of rebuilds at AK (audiokarma) also.
Maybe like this model?
http://www.shedradios.com/MAG1ST606.HTML
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Here's a nice site with an article on how to rewind a PS trans.
Tronola DIY Electronic Projects and More
Tronola DIY Electronic Projects and More
It's much more likely that the Power supply filter capacitor died. May be a resistors fried also. You need to learn how to post pictures so you can be helped. Do you know how to use a VOLT/OHM meter???????????????
Can you read a schematic diagram???????????????????? Do you know how to solder????????????? Do you have basic hand tools?????????????
All these questions need to be answered.
Can you read a schematic diagram???????????????????? Do you know how to solder????????????? Do you have basic hand tools?????????????
All these questions need to be answered.
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