Stupid Me Yami RX-550 issue

Ok so I'm an idiot! the input switch on these units is notoriously bad...mine was no different...fuzzing out the channels...wiggle, wiggle,,,thats better...then more fuzz...

I finally break down and crack the case to clean it...

Its packaged in a metal box soldered to the board...so I desolder it and pull the case...pop off the sweep from each dial switch...diligently clean the contacts and the sweeps...(BTW they were REALLY dirty) re-snap the sweeps in place and re-install the metal case.....then....then...Here's where the self inflicted DOPE slap should have been delivered...I realised I had FAILED to note the alignment of the individual dials before I removed the shaft...

NOW the unit goes into safe mode and instantly powers down when ever I select ANY location other than 'TUNER' ...

The switch is available, and if need be I will buy a new one and install it...but I figured I would start here first...

I re-assembled the unit and when it first powered off, I realised my mistake so I immediately broke it down again and I currently have all of the 'arrows' aligned...but upon re powering and tyring to select a different input location...it instantly powered down again...

does ANYONE know the proper alignment of these damn dials...

thanks

Rob

Pics of the switch?

Sorry...here are some pics...

Have you set the receiver to aux or phono, and lined up the switches accordingly? Maybe drop the motor and set it up by hand?

The ONLY way you are going to be able to do this is get a schematic, look at the individual switch positions for one input, align them with a multimeter one at at time, and reinstall the shaft. They can only be 180 degrees out of phase with each other, so there aren't that many combinations. Once the switches are aligned for one input, they will be correct for all inputs.

Good luck!

unfortunately, without any schematic I have no way of determining what position is what...as I shot the pic's I tried re-aligning again and got bupkiss in all positions....I'm certain that two are for the RT/LFT channel's and that one has got to be for the LED display (tunner/phono/aux/etc...) so...not quite sure what the 4th does...but I'm reasonably certain that the mis-alignment has errant DC current running about where it's not suposed to be, hence the relay tripping to "safe mode"...don't want to damage (if I haven't already) some vital circuit...but with only 4 pots and each having only a 180deg. option...I should be able to suss it out in 16 tries...but I don't want to 'F-up anything in the process

There's a schematic for an AX-550 in the Yamaha database. Is it similar to yours?

According to the various "fitment" guides the replacement switch VT176900 fits
AX-470, RX-550, RX-570, and RX-770

but the AX-550 LOOKS to have a similar switch...where is this database of which you speak...I see Yamaha not represented in the Manufactures Forums

Follow the instructions in the pdf:
http://www.audiokarma.org/forums/showthread.php?t=154865&highlight=yamaha+database

Ok...the database had a schematic for the AX-470...this unit uses the same switch (possibly the exact same output CB) ...so later tonight I'll have-at-it and see what happens

ok...the latest...I've got the switch together...and the unit no longer powers down when rotating in...but now I get no display...

Well, dang, you gone done and broken that thang!

Everything works except the display?

seems to...speaker relays fire...pure direct light lights I havent hooked up speakers yet...but then I wouldnt know what was what (other than trial and error)
the schematic for the ax-470 (which claims to use the same switch) only shows 3 switches...the 4th seems to have only 2 contacts (on or off) the 4th is the front one which has the female receiver for the geared tang on the shaft it turns independantly of the shaft (and is coged to provide the fixed rotation)

Well, phooey. I have a manual for a 450, but that uses a backlit LCD display, not a tube. Plus, it doesn't use that switch scheme. I don't seem to have any other manuals from the RX-X50 series, so I don't think I can help.

I went out and scoured for a free manual or schematic, but can't seem to find one. You may have to buck under and buy a scan from one of the manual houses. I forget who everyone recommends, here, but he is spoken highly of.

Wish I could help better.

That would be Rick Stout @ Stereomanuals.com. Fastest Damned thing I ever seen. Ordered a Fisher 49A/49T (Amp/Tuner) Manual this past Friday right before noon. Had in my hand @ 11:15AM on Monday. I didn't know they still had PONY EXPRESS(They wore out the horses)!!! And the Manual is good enough I can read it WITHOUT my Trifocals(it's on 11x14 paper and card stock.). Really well made and worth twice what I paid for it.

Larry

why would you tear it so far apart? not necessary

I had the same problem with my RX 550. Thanks to the fantastic photos that Rsclj posted, I was able to resolve the issue without disassembly.

I sprayed a liberal amount of Deoxit 5 in the can, alternating between spraying and rotating the input knob.

I would recommend putting a paper napkin or rag under the input selector can to catch drips. I didn't do that, and the spray got everywhere and soaked into the circuit board underneath. Then I had to use napkins, a hair dryer, and waiting time so it could dry out.

I've read that Yamaha has replacement switches available with gold contacts. If anyone finds a part number, please share!

I was actually really fortunate one showed up for sale local with the exact same problem...so for less than the price of a new switch I bought it...opened it up...rebuilt the old one according to the new one...deep cleaned them both...gave one to my Dad and kept one...

Any updates on this?