Home Theater Questions? Ask a Technician for Answers ASAP
Hi Louie, we have worked before, on aVCR combo I think.
with the Sherwood RX4503 I have checked the 230v mains through to the main board, checked the primary and secondary windings on the power transformer, the on off switch on the front panel. there are no signs
of heat stress any where. I have never worked on a unit that has a small instrument type transformer to supply a low control voltage for relay operation and start up etc. I am just at the stage where I am about to remove the main board and have look underneath. Are there any voltage checks I should do before that ? Ray
Hi Louie, I`me back, had a few dramas around the ranch ! Well, the small control transformer is OK, and producing a nominal 5 v DC out. this comes and goes with the operation of the front panel on off switch. I have done a diode test to all the semiconductors and diodes in the area, and all the coils of the relays are OK, including the back EMF diodes across the coils.every thing seems good. can't help thinking I am missing something here. With out a circuit of the relay drivers etc. I am really working in the dark here. RAY.