yamaha ax540 help relay

so lookiing for help or info on how to fix this beautiful yamaha ax540 so all rca work head phones work no sound out speakers but if i hold a speaker wire on the bottom of the relay i get sound out of the speakers so i changed out the relay still same thing changed out the resistor same thing the relay is not getting power is what im thinking i end up ordering ceramic caps hoping thats it any ideas would be great
 
First you need to download the service manual ... HERE

Next, you should stop randomly replacing parts and ordering stuff until you can find out what the exact problem is. You can waste a ton of money that way. These things almost always trace down to a single inexpensive part.

So, do you have a multimeter?

I'm guessing that you know a little bit about service already since you changed the relay.

The ax540 has switches for two sets of speakers... please ensure both are turned on.
It also has two relays, one for the A speakers one for the B set.
So you need to listen when powering up to see if at least one of them clicks in or not.

I would think that if neither of them is pulling in you may have a problem that is driving the amplifier into "protection" mode.
 
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Alrighty ... do you have a multimeter? You're going to need one to do this.

You will also need the Service Manual on hand. I suggest you get the same one I did, so we're sure we are both on the same page.

I'll guide you through it, but you're going to have to do the readings for me.
i have to go out and get one the manual i can get online i looked at them i all so been useing learing the circuite youtube page and Mr Carlson's Lab on youtube for soldering tips were im from i have no one around me to fix vintage stereo so im kind on my ownso i thought if im big into hifi and audiophile its something i should try to learn
 
this insid dont look that bad dont see anything that looks burned out
 

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the relay dont even click at all no sound from it why i thought the relay was bad there so i was thinking its some thing to do with power thats why i end up changing out the the resistor the relay board is diffent from the main board so i was thinking it was something on the relay board because nothing looks burned out were the wires go to the main board but i get sound out of the headphones and on the bottom of the relay if i hold a wire i did just see the old relay was 24vdc 5a40vc 5a24vdc the new one i order the right one onlinee but send me 48vdc 5a40vac 5a24vdc idk if that matters
 
i get sound out of the headphones and on the bottom of the relay if i hold a wire i did just see the old relay was 24vdc 5a40vc 5a24vdc the new one i order the right one onlinee but send me 48vdc 5a40vac 5a24vdc idk if that matters

Yes it matters ... there is no way a 48 volt relay is going to pull in on 24 volts.
So, first thing start by putting the old relay back in.

If neither relay is pulling in, your problems lie elsewhere.

I can't tell exactly what's wrong by staring at the schematic. We need to get voltage readings from various points in the circuits to determine what the problem is.

Now.. again... do you have a multimeter?

If you don't, I'm not going to be able to help you (nor can anyone else online) and your best bet is to take it to a qualified technician.

Also, while you're at it... if you want to learn about electronics you need the underlying theories of how things work... You should visit the link in my signature and start reading...
 
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Douglas Blake i did what you said to put the old relay back in and it worked im shock because when i got it it had no sound so im guess the solders were bad or really was the two small resistor i changed out im just so happy for your time and leittle help u ave me ill be posting more suff down the road like i said i need to learn much as i can to fix my own stuff no vinge repair shops by me uless i driver 2hr away or more god i hate PA
 
Douglas Blake i did what you said to put the old relay back in and it worked im shock because when i got it it had no sound so im guess the solders were bad

Very good ... What I would suggest is that you take and retouch all the solder on that relay board. Heat, vibration, age, etc. all add up to the occasional joint that goes bad.

The best technique is to get your iron a tiny bit extra warm, touch each point for about 3 seconds (or until the solder melts) then using fine solder add just a tiny bit of fresh solder... then move to the next one. Don't be surprised if some of the solder joints boil when you heat them...that's a common problem with mechanically soldered boards.

While you've got it apart, you should clean all the switches and controls. Just take an eyedropper and some rubbing alcohol, put a couple of drops into the switch or pot and operate it a few times back and forth, end to end. That will get rid of accumulated dust, nicotine and what have you.

From there, you should be good to go!

i said i need to learn much as i can to fix my own stuff no vinge repair shops by me uless i driver 2hr away or more god i hate PA

Of course, and your interest is commendable. That's why I have the All About Circuits link in my signature. Anyone starting out needs to know more than swapping parts or good soldering... to successfully diagnose a problem you also need to know how each little bit in a circuit works. Electronics is about half theory and half practice, one is no good without the other.

Thanks for the good news.