They say three house moves equal a house fire. Well, my old Yamaha R-90 endured two moves over the last five years, but finally quit on the third one.
It powers up; all displays light up (tuner, equalizer, source selection indicators etc) and all buttons work. BUT there is no "click" that would follow a few seconds after power up, and there is no sound, not even the slight rustle I'd sometimes get turning the volume knob, not even in the headphones jack.
From the reading I did, I understand the absence of a click is sign of a relay not functioning. I have a multimeter and the service manual with schematics but I don't know how to read schematics, so I don't know where to find this relay.
I live in the boonies, so there is no hifi repair shop near me. I gotta do this myself.
Any help is appreciated.
Here be the service manual with schematics:
hfe_yamaha_r-90_service_en.pdf - Google Drive
It powers up; all displays light up (tuner, equalizer, source selection indicators etc) and all buttons work. BUT there is no "click" that would follow a few seconds after power up, and there is no sound, not even the slight rustle I'd sometimes get turning the volume knob, not even in the headphones jack.
From the reading I did, I understand the absence of a click is sign of a relay not functioning. I have a multimeter and the service manual with schematics but I don't know how to read schematics, so I don't know where to find this relay.
I live in the boonies, so there is no hifi repair shop near me. I gotta do this myself.
Any help is appreciated.
Here be the service manual with schematics:
hfe_yamaha_r-90_service_en.pdf - Google Drive
Attachments
Update:
I located the speaker relay (RLY401) and opened it up.
It reads 53V DC on one of the contacts and 3.6mV on the other. (taking the chassis as negative)
When I manually close the relay, I hear a hum in my left ear (using headphones) but its silent on the right.
So, where do I go from here.
Again, many thanks.
I located the speaker relay (RLY401) and opened it up.
It reads 53V DC on one of the contacts and 3.6mV on the other. (taking the chassis as negative)
When I manually close the relay, I hear a hum in my left ear (using headphones) but its silent on the right.
So, where do I go from here.
Again, many thanks.
Funnily enough your check on the relay voltages ( or lack of ) was replicated in 2012 on another website by a poster with the same symptoms but his output appears blown at least in one channel seemingly like yours .
The speaker feed relay protection has cut in .
I cannot access Google as I have blocked it from network access but will try to get a schematic elsewhere.
Have a read-
Speaker relay on Yamaha R-90 receiver not closing | All About Circuits
The speaker feed relay protection has cut in .
I cannot access Google as I have blocked it from network access but will try to get a schematic elsewhere.
Have a read-
Speaker relay on Yamaha R-90 receiver not closing | All About Circuits
Aw man. The user gives up at the end of that thread and decides to chuck the whole thing out. That's demoralizing.
I just attached the service manual for your viewing pleasure.
I just attached the service manual for your viewing pleasure.
Channel 53v is faulty. First of all, check the contacts and fuses. After this supply voltage. With the power off, check with a multimeter powerful transistors and drivers as diodes from the base.
Yowser, don't do that. If you had speakers hooked up, you likely would have blown one out. If the protection relay is not pulling in, that indicates a fault in the amplifier, and you need to find that. If you are seeing an offset voltage of 53 volts on one channel, it is likely that you have one or more bad transistors (commonly the output transistors).
Unfortunately that 'service manual' does not contain a schematic, which make it next to useless. A quick search on my part did not turn one up either. Remote troubleshooting without a schematic is very difficult - good luck.
Yeah, I'm starting to feel like a monkey with a hand grenade. I think I may quit before I damage any more of my equipment.
Thank you all for your time and advice.
Thank you all for your time and advice.