Some problems I am having with a Onkyo TX-844 receiver

The Shocker

Super Member
I picked up an Onkyo TX-844 receiver from someone on Craigslist for $25 on Saturday.

The receiver is giving me some issues now, and I would like to try and see if I can crowdsource an answer.

When I set it up and on Sunday morning, the left channel was weaker than the right, was cutting out and producing a lot of static.

So, I pulled out the deoxit and cleaned the speaker terminals and that helped give me a stronger left channel, but it still got static. I next cleaned the Volume knob and the balance knob with Deoxit. This also seemed to help, but wasn't 100%.

Next, I cleaned out the RCA jacks on the back and that seemed to help a LOT. The thing sounded great.

But that did't last all that long. If I power it off and back on or turn off speaker A and turn it back on (from the speaker selector switch), the static will come back, and the left switch will cut out.

The only way I have been able to fix it, is to crank the volume to about 50 percent and lower it back down to an acceptable level. That has always fixed it and brought the left channel back to normal.

I think a good first step would be to give it the full deoxit treatment and see if that fixes anything.

But I am curious if these symptoms are indicative of any kind of major problem that a Deoxit treatment may not fix?

EDIT: Yes, I did test the receiver. But I tested in his living room with the volume cranked up much louder. Which is when it works flawlessly. Also, I am sure the owner would probably refund my money, but it was only $25 and I drove 40 minutes to get it. An hour and twenty minutes of time is worth more than $25 to me right now.
 
Relays.

Just cleaned em in my TX-SV90Pro yesterday and it solved some issues with the unit, but I learned about it with a TX-904 and later a TX-906.

Easy to open and clean. But the correct solution is to replace the relay, ask any tech. But these are easy to clean. I replaced them in the TX-904 and have one broken open one that I learned on and one spare bad one I can clean and use probably.

Let me go get pics.

Relay is the black box 1½"x½" and the top can be pried off and then you can see the contacts below a plastic part which can be moved out of the way (it has pointed ends that go into the holes in the end of the contact pieces). Then I used a deoxit soaked piece of cardstock to clean the relays, pushing the contacts closed and repeating a few times. The power relay dirtied the cardstock a couple times the speaker relays, 3 of them only dirtied one side.
 
OK pics now.

Relay:

Onkyo Relay 2.jpg

Tops of relay:

Onkyo Relay 1.jpg
Notice the white plastic piece in the lower relay in the pic. It needs to come out and when you push the relay contact on the pin (left end of the white plastic) the piece will lift up. Do both contacts and you can manipulate the removal of the white chunk. Clean the relay, moving contact and the fixed contact closer to the wall of the relay and then reinstall the white chunk then put the tips through the relay contacts and snap the cover back on. 20 minutes if the relays are easy to get to. A small jeweler's screwdriver will fit into the gap between the top and sides of the relay and you can pop the top off very easily compared to the clear covered relays in lots of this gear.
 
I do it in situ since the top comes off the relay. I had to move some boards but the 90Pro is a lot more receiver than the 844. Pop its top and let's have a look around.
 
you have three relays one for A one for B speakers and one for headphones. Doubt the B-speaker relay has been used much at all. When you put the unit back in service, use the B-speakers and you should get lots of life from the unit.
 
The 844 is a nice receiver. I used to have one as my bench receiver when I repaired audio for Fretter. You are better off replacing the relay. The speaker relays get tarnished when the protective plating wears off the contacts. Cleaning will work for about a month and then it will oxidize again. There are 2 different relays in the unit; 2 of one and one of the other type. You have to remove the relays, and make a drawing of the pinout, with measurements between the pins, in mm. then go to Digieky and search for power relays, DPST, 24VDC coil voltage, 5A contact current at least. Then find one that has the same pinout and spacing. Panasonic is your best bet.
 
Arrow has the Omron and free shipping
Digikey has free shipping if you send them a check

Omron G2RL-2A-DC24 is the relay someone said would work in a thread where I was asking about the relay for the 904, years ago it is the same number as the one in the 844.

If you don't have the problem on the B speakers, you can use it while you want a day or three for the parts to arrive and install. I did say that replacement is the best course of action. I won't tell you that I used the 906 in the bedroom for a couple years almost nightly and the cleaned relay worked just fine and still does but it is now a basement receiver the HK stack took its place.
 
Arrow has the Omron and free shipping
Digikey has free shipping if you send them a check

Omron G2RL-2A-DC24 is the relay someone said would work in a thread where I was asking about the relay for the 904, years ago it is the same number as the one in the 844.

If you don't have the problem on the B speakers, you can use it while you want a day or three for the parts to arrive and install. I did say that replacement is the best course of action. I won't tell you that I used the 906 in the bedroom for a couple years almost nightly and the cleaned relay worked just fine and still does but it is now a basement receiver the HK stack took its place.
The B speaker actually sounds worse than the A speaker.

My soldering stills are not nearly what they should be, so I thought I'd call in professional help. I called a place that specializes in repairing vintage receivers and they quoted me $175+ parts to replace ONE relay. Considering what I saw on YouTube and the service manual, this is a 15 minute job, if you know what you're doing. $175 labor for 15 min of work seems high.

80s and 90s era receivers are dirt cheap on Craigslist. I can probably nab something for $25-$50 that will get me by, until I can get these relays replaced.
 
Are the speaker relays a known point of failure for these receivers?

Is the recommended Omron G2RL-2A-DC24 going to last longer than what's in there now?
 
clean what you have no soldering needed.

No relay is going to last longer unless it is much higher capacity and that capacity was the cause of the failure of the ones you have now.
 
Then you have electrical issues that will require a tech and it might not be cost effective to have it repaired. Some here might attempt a repair but they have probably done some soldering. Oh well, we tried.
 
As I recall, this receiver does not have a bottom panel that is remove-able. To replace the relay you have to remove the entire pc board. Not a 15 minute job.
 
Greetings;
Depending on your location, you can advertise on Clist in gigs or electronics asking for someone who has the soldering skill and perhaps also dabbles in gear repair. Flip is shelve it and get another amp as suggested and start practicing soldering skills.
 
Thank you everyone for your help. I think this one is a goner. I may try a little more deoxit in a few places and then give up. I could try and get a refund from the seller, but the drive to get back $25.00 is more than I want to deal with. I think it's time to hunt craigslist for another vintage receiver.
 
UPDATE!

Took it apart again and decided to "go crazy with the dexoit."

Sprayed the volume pot all over. There as a small hole in the POT, so I sprayed some deoxit in there and then worked the knob back and forth for about 30 seconds.

Then I went to the speaker terminals. The posts on the inside connect to a small PCB, and a ribbon cable comes off the PCB onto the main PCB right next to the relays. I sprayed the internal posts, the PCB (both sides) and the connector where the ribbon cable met the mail PCB.

I let it sit for 15 minutes and then put it all back together.

Speaker cutout is completely gone. Only the tiniest bit of static when I adjust the volume that now seems to be gone after a coupe of volume adjustments.

I think I can call it Good Enough™, and put it to use. Blasting some Green Day and it sounds great.
 
You are not supposed to spray cleaner all over the board. That does nothing, makes a mess and the oil left over attracts dust. You inject it into the controls through any opening you can find, then work the control back and forth about 30 times.
 
You are not supposed to spray cleaner all over the board. That does nothing, makes a mess and the oil left over attracts dust. You inject it into the controls through any opening you can find, then work the control back and forth about 30 times.

I know that/ But at this point the receiver was a goner. So, I just wanted to experiment. Right now at 9:00 PM at night, it seems to be working OK. I'll keep using it until ti fritz out on me, and then I will pass it on to someone who wants to fix it and get another receiver.
 
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