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Onkyo stereo receiver TX8500 Mkii

I recently acquired an Onkyo TX8500 MKii stereo receiver and would like to find a user/instruction manual (Part #29340277). I downloaded the service manual however it doesn't explain how to use the radio station presents, the locking switch, etc. Additionally, there is an "EPS" on/off switch on the front and "EPS" in/out jacks on the back that I don't know anything about. Can somebody provide information?

Re: Onkyo stereo receiver TX8500 Mkii

I had that unit back in the day, that had 160 watts per channel with two separate power supplies.
the EPS stood for External Processing System. the locking switch was to turn off the auto lock, some weak stations it would lock on a strong mono. with the switch off, you could tune to stereo but it might drift. it is a very large/heavy system, and would not fit in the stereo cabinet. I had a Onkyo 4500 before that, but it was stolen. I bought this so the next thief would get a hernia....

Re: Onkyo stereo receiver TX8500 Mkii

Thank you, Flip (from Jersey), I appreciate the reply. The EPS seems to be there to accommodate a mixer or other signal processor. I need to play with the FM stereo lock a bit to fully understand it and your reply helped me, thanks.

Since I posted, I've stopped using the unit - it began breaking up in the right channel by cutting out and intermittent distortion, also in the right channel. I switched the speakers from line A to B and the problem persisted. I connected the speakers to a different receiver and the problem did not reappear - so it is not in the speakers. I plugged in a 1/4" to 3.5mm headphone jack adapter to see if the problem persists in headphones and the first thing I noticed is that the channels are reversed! There seems to be significant portions of the signals missing in the headphones but hard to tell about the distortion. Oh well, I wanted a project when I bought it...

Since this is my first attempt at a refurb (Big unit for a virgin) I think my plan is to first use Deoxit on all the switches and connections, followed by Deoxit Gold to lubricate and preserve. Then I plan to buy all new electrolytic capacitors, maybe not the 4 big 85 volt power supply units at first, but everything else. If there are any ceramic capacitors I will leave them in place for now as most posts indicate they seldom fail. I don't have an oscilliscope so I don't want to do anything that would require me to make fine tuning adjustments. (I am learning about electronics by reading books and posts and my tools consist of a solder station and multimeter.) How hard can it be? I'll replace the caps one at a time then turn it on when I'm done.

I will also buy a replacement speaker relay - I will try cleaning it first, but have a new one on hand in case I biff it.

Does this sound like a reasonable plan? I really want this to work because the thing sounded awesome for a short time before it started breaking up. After all, it is 37 years old...wish I was.

It is a beast, about 65 pounds and too big for the cabinet but I will deal with that when it is up and running again.
Thanks, and Cheers,

Re: Onkyo stereo receiver TX8500 Mkii

I'm not the one to ask, I loved this unit, except for its's size (had to put turntable on a shelf, and the 8500 on the top of the stereo cabinet). I stopped using it cause I took mine apart to clean it, and thought I Could put the cover back on, while listening to it, and I blew out the dial lights by fumbling with the screwdriver. So I eventually just gave it away, to a friend. I have to get that Deoxit spray myself, just picked up a Marantz twenty twenty, and the balance and other pots have some static, when turned. Will look to see if i still have the operating manual in a file.

Re: Onkyo stereo receiver TX8500 Mkii

Thanks Flip, I appreciate it. Before I take it apart for close inspection I will come up with a plan. It would be awesome if you had the manual that you could share. It is really big, but I will make room for it when it has been restored to factory specs.