Looking at fixing this amp, had the protection (red) light come on just before it stopped working, now won't turn on.
Found that there are no blown fuses and getting power to the transformer but only getting 5V on one secondary winding and nothing on the other so need to replace the transformer.
The only info that I can find is as follows.
Sony Es audio transformer- 1-448-632-11 (0.5kVA)
I have the E model with voltage select, only require 240V though.
Just wondering if anyone knows what the secondary design output voltage should is?
Also, If i was going to replace and eliminate the voltage select function would this effect any of the protection circuit function?
Unfortunately I can only find extremely blurry copies of the service manual and from what I can make out it doesn't appear to have this data in it.
Found that there are no blown fuses and getting power to the transformer but only getting 5V on one secondary winding and nothing on the other so need to replace the transformer.
The only info that I can find is as follows.
Sony Es audio transformer- 1-448-632-11 (0.5kVA)
I have the E model with voltage select, only require 240V though.
Just wondering if anyone knows what the secondary design output voltage should is?
Also, If i was going to replace and eliminate the voltage select function would this effect any of the protection circuit function?
Unfortunately I can only find extremely blurry copies of the service manual and from what I can make out it doesn't appear to have this data in it.
Web archives of the schematic do have some faint indications of the raw DC supply from the main rectifiers. From that, it should not be difficult to calculate the AC feeding the main bridge rectifiers and hence the AC voltage from the transformer.
As you say, the schematic is blurred and the voltages are also marked in pale (originally coloured, I guess) text but after looking at several examples of the same voltages, I believe it reads +/- 50VDC unregulated, which generally corresponds to approximately 35VAC main secondary windings or in this case, actually a single 70V CT winding. The VA rating and original E-I laminated type of transformer will likely be important for keeping the amp operating safely within component ratings too.
As you say, the schematic is blurred and the voltages are also marked in pale (originally coloured, I guess) text but after looking at several examples of the same voltages, I believe it reads +/- 50VDC unregulated, which generally corresponds to approximately 35VAC main secondary windings or in this case, actually a single 70V CT winding. The VA rating and original E-I laminated type of transformer will likely be important for keeping the amp operating safely within component ratings too.
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