I'm servicing a friend's Rotel RX-855 receiver.
It has two mains transformers - one for each channel. One transformer has only one output ie AC1/AC3 in the schematic. I think it provides +/- 40V DC when rectified.
The second transformer has failed (low impedance primary) and has two outputs, one the same as above (AC2 and AC4 in the schematic), plus an additional AC output (AC5 and AC6) which is used for additional circuitry. Can someone please confirm the output voltage for AC5/AC6 - I may need to source an aftermarket transformer if I cannot source an original. Or alternatively, point me to a source of replacement transformers.
It has two mains transformers - one for each channel. One transformer has only one output ie AC1/AC3 in the schematic. I think it provides +/- 40V DC when rectified.
The second transformer has failed (low impedance primary) and has two outputs, one the same as above (AC2 and AC4 in the schematic), plus an additional AC output (AC5 and AC6) which is used for additional circuitry. Can someone please confirm the output voltage for AC5/AC6 - I may need to source an aftermarket transformer if I cannot source an original. Or alternatively, point me to a source of replacement transformers.
Talking about other TX (with two more secondaries):
It feeds various minor areas and also supplies the DC for the microprocessor 5.9v supply.
The 1A is the clue to curent rating. (I'd guess it's ~half that in reality)
If the O/C is on the primary and you have a variac you could check if the 110 or 120 winding is intact , and run the amp up on that to confirm.
It'll look a bit of a dogs dinner but if you're intent on repair I'd suggest a couple of toroids, otherwise seek out a secondhand donor.
- AC5/AC6 ultimately feeds/creates a low current 22VDC rail from a full wave bridge, you can work out the AC secondary backwards from that.
It feeds various minor areas and also supplies the DC for the microprocessor 5.9v supply.
The 1A is the clue to curent rating. (I'd guess it's ~half that in reality)
- AC1/AC2 (very low voltage and current) is the rail for the FL display (usually 4 to 6VAC)
If the O/C is on the primary and you have a variac you could check if the 110 or 120 winding is intact , and run the amp up on that to confirm.
It'll look a bit of a dogs dinner but if you're intent on repair I'd suggest a couple of toroids, otherwise seek out a secondhand donor.
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