freebie (broken) Marantz SR18

[mikepukmel]

Hi All,
A guy had a broken Marantz SR18 for sale for a while, dropped the price then gave it away. I was lucky (maybe?) to be first in line. I picked it up, and started browsing for schematics and was discouraged to find that even this old unit, its hard to find detailed specific schematics. And Marantz is nasty and mean when you ask for repair info even on 20+ year old equipment. Ah, well.
Plugged it in, and it boots up. Relays click on, it goes through some self check, turns the relays off, then displays an error message code on the front panel. I found some version of a troubleshooting manual that doesn't have this specific error code, unfortunately.
I dug around a little, found a few repair videos, real pro's fixing these, but didn't find anything specific to this error message. I think they don't like to give away trade secrets, understood!
what I was able to get from the few posts on this monster, is that the power supply board has lots of problems. There are a whole bunch of regulators on that board, and the repairs people talked about, they seem to replace parts on that board quite often. Its got a big pile of circuit boards, and the power supply board is way down on the bottom. Real bear to get disconnected without breaking those tiny plastic clips, and when i got it apart, all the cables were removed, so I could not measure anything.
General question: how the heck do you measure outputs on regulator boards way down in the bottom of a stack of like 6 huge boards, if you have to take the whole thing apart to get at the board? I can't see people taking it all apart, hooking up probes, putting it back together, doing a measurement, then taking it back apart to remove the probes. It seems like you have to somehow take it apart, but leave all the connectors connected, and tilt the upper boards "up" to be able to get probes on that bottom board. Or maybe, only leave the power supply board hooked up fully, but remove the other boards, and probe the ps board with just its inputs connected? (But then, nothing would have a load on it, so ... is that good?)
THanks
Mike
Happy New year

[nosaj]

Some recievers you can remove the bottom of it providing access to the lower levels. What is your error code. I included the service manual.
nosaj

[g1]

Sometimes you need extension cables that allow you to hook the boards back up while disassembled and laid out on bench. They are usually only available to authorized service centers.

[mikepukmel]

Some recievers you can remove the bottom of it providing access to the lower levels. What is your error code. I included the service manual.
nosaj

Thanks! I haven't run it in ages, will crank it up again and get the error code (should have written it down). thanks for the manual!

[mikepukmel]

Sometimes you need extension cables that allow you to hook the boards back up while disassembled and laid out on bench. They are usually only available to authorized service centers.

Akk, I hope I can diagnose it without proprietary cables. Every time I pass by it, sitting on my son's old lincoln logs cart in the basement i think I either have to get it working or ... get it working. I can't toss it, its got these HUGE toroids and ps filter caps. I bet it sounds way better than my 25.00 throw away sony. (Good lord that thing sounds awful).

[mikepukmel]

Ah found it, actually was an email to Marantz: ERROR PWR2
its not in the repair manual, and the person responding to the email tech question apparently just looked in the manual (the one you sent Nosaj), not there so they said to send it in for repair Anyway, PWR has to be power supply something or another but dang look at all the power supplies in there! If I actually fix this thing, Im going to buy myself a beer. maybe two. If I can get some repairs done around the house my wife won't complain so loudly at me taking up the table in teh basement to take this thing all apart agian.

[J M Fahey]

No need for expensive/unobtanium extension cables.

Just cut as many as needed 40cm pieces of regular #20 or #22 single wire as you have voltages plus one for ground (donīt trust the chassis for that), so0lder one end each to proper pad (donīt worry about connectors either), tape other exposed end to a piece of wood, label them and reassemble the amp.

Turn it on and measure under real conditions whatīs wrong/missing.

Youīll still need to reopen to repair the broken supply section, but you can do that without the rest of the amp, if needed load suspect section with a proper resistor or something.

Plan B-C-D...Z: gut it, keep power transformer, cabinet, heatsinks, and build something powerful, nice and simple inside.

PS :those 40 cm wires will later be useful when assembling something else or for other testing.

[The Dude]

The first thing I'd try is a factory reset. I believe it's this. With power on, hold down CL and DISPLAY OFF for 3+ seconds.

[mikepukmel]

Thanks everyone! I have gotten some new drive to get this unit working: my wife has started "cleaning" the basement and ran across an old turn table, a rack mount computer case, and this reciever, which could disappear while Im away at work <frown< unless i get them working.