SX-1010 Dimmer button problem...

Hello again fellow AK'ers.

I've recently acquired a couple more receivers, a SX 1050 that has more problems than I care to try to tackle (Man, did I get burnt on that one!) and the other is a real nice SX 1010.

I was able to see/touch/listen to the SX 1010 before I made the purchase. It had been running for 4+ hours when I got there, and sounded real good on the guys nasty old "test" speakers. All of the lights worked, including every one of the function lamps. The wood case was great, except for some fairly minor chipping on the bottom of the left side. The faceplate needed a good cleaning, but was in great shape, and all lettering intact. None of the pots sounded dirty at all, but most of the push-buttons on the front panel were dirty/intermittent, especially the -20 dB cut. Tuner worked OK, tuned up and down the dial fine and reception was OK, might be a bit better... but OK. AM antenna socket broken like most of them are, with all of the loose parts in an envelope.

Here is the main problem area. When I tried the dimmer switch the dial lamps went out. Pushing it several times eventually got them to come back on "somewhat" , but you could tell it wasn't right. I hoped a real good cleaning would fix it (and the dirty push-buttons), so I bought it.

When I got it home and tried the dimmer again, the lamps would not work at all. Pushing the button over and over again would make them work somewhat, but when you let the button rest in place (on the bright selection.. "out") they usually wouldn't work at all, or at best would work halfway between bright and dim in strength... and flicker every now and then. Pushing the button in just an 1/16th of an inch would light them up brighter.

So I cleaned all of the push-buttons above the pots, including the dimmer and FM muting. That really helped, but didn't fix it. They stay on 85% of the time, with the button all of the way out. And if they go out, another push in and out of the button will bring them back on. Although the lamps aren't dim, they are not exactly at 100% brightness. Again, pushing the button in about 1/16 of an inch would bring them up to full brightness and stable. If you could only adjust the "throw" of the push-button so it wouldn't pop out so far they would stay on all of the time, and very bright. It's to bad there is no adjustment to do that.

My questions are... I can't recall ever seeing this switch panel with both buttons anywhere for sale. Maybe once every blue moon you'll see someone part a receiver out... but their switch panel will be just as old/used as mine and might not be any better. SO... if I can't locate a good donor switch, could I use a small jumper across a couple of pins on the board to make them stay on (on the bright side) whenever it is running? I've really cleaned the living hell out of it (twice, working the switch for 10 mins. each time) with DeOxit D5 and don't think it will clean up any better than it is now.

I'd like to keep it as original as possible, but I want to have the lamps lit at 100%, stay on, and be stable (not flicker). I hate to bypass the switch, even though I would hardly ever use the DIM side, but I can't think of any other solution.

Any ideas? Any help would be greatly appreciated! Thanks.

Pioneer SX-1010 Dimmer Switch DEFEAT Method

DANGER:
When shorting the switch in one position, if you switch to the OTHER POSITION, it will put a dead short across two transformer taps. That's a GUARANTEED FIRE !!! IT *** WILL *** LET OUT the magic smoke.
YES you can permanently select bright / dim BUT NOT AT THE SWITCH!!!!!!
THIS IS THE ONLY WAY to eliminate the fire hazard.

OK, hold onto your hat, this is going to get windy.......

There are two unrelated lighting circuits going through that poor switch.

One set of circuits uses 3 of the four sections of the switch connected together to try to share the load, they are carrying about THREE AMPS of current!!! The switch is powered by the blue (bright) and violet(dim) wires from the big power transformer, which are two different AC voltage taps on a transformer winding.

These lamps are:
the six 300 mA dial illumination lamps
the two 300 mA meter illumination lamps
the three speaker lamp indicators
the 50 mA dial pointer

and I suspect these are your main culprits.

BUT, there's ANOTHER LIGHTING CIRCUIT. IT is a DC circuit that is a rectified version of the violet wire from the transformer. And that last remaining fourth switch section is used to short across TWO additional series diodes. This means that if THAT switch section goes bad, you STILL have the DIM lights working, as the current can flow through the diodes that do the dimming, you just can't get the bright setting.

These lamps are:
(only one at a time) AM, FM, PHONO 1, PHONO 2, MIC, AUX
the stereo indicator lamp
and in a nasty little switching circuit which you should be able to ignore for now
the Low Filt, Hi Filt, AF Mute, Mono/Stereo and Loudness lamps.

So literally the bottom line is,
YES you can permanently select bright / dim
BUT switching to the OPPOSITE selection when there are shorts at the switch will put a dead short across those two transformer taps. YOU WILL HAVE A FIRE.

You CANNOT just pull a fuse to isolate the dim (violet) winding as that would cost you that other lighting section.

You must CUT and MOVE ONE WIRE, the AC lamp's feed AT THE BOARD'S connection, then on the other DC lighting circuit
a short across two other pins can be soldered in place.

You will see two groups of pins on the AWS-068 board, one group of four and one group of three.
Pin #4 can be identified from EITHER side, as the centermost pin of the group of four pins, and pin 5 is next to it opposite the gap.
Pins 2 & 3 are on the OTHER side of the gap, in the group of three.

You MUST DISCONNECT the wire going to PIN #4 of the AWS-068 board that the dimmer switch is mounted to, and connect it to pin #5 of the SAME board. There MUST be NO remaining connection to pin 4, a "shortcut" of tying pins 4 and 5 together IS WHAT CAUSES THE FIRE...

Then for the other lighting circuit, you CAN put a short across pin #2 and pin #3. It will probably be easier to reach, than trying to get at the actual switch's soldered connections on the pc board.

The 'foil' piece of the switch that makes and breaks contact takes a lot of abuse and gets burned up (there's a lot of current going through it).

I've disassembled a few of these switches and taken the 'foil' piece of the switch from a spare one and put them into the dimmer switch, and you're good to go for another 30 years.

I found it interesting that he didn't comment (notice??) that some of the lamps were still lit dimly while the others were out.

Also interesting is that the half wave rectified violet tap off the transformer for the DC lighting group has 4400 uF of capacitance on it, all because the stereo lamp has to run off of it.

markthefixer said:

I found it interesting that he didn't comment (notice??) that some of the lamps were still lit dimly while the others were out.

Also interesting is that the half wave rectified violet tap off the transformer for the DC lighting group has 4400 uF of capacitance on it, all because the stereo lamp has to run off of it.

Click to expand...

Mark, To answer that comment... when the lamps went out, the only lamp that was lit was the function lamp (FM, Aux, etc.), and it looked to be at regular brightness, not dimmed. Your explanation of how the circuit is wired is explained clearly, so I understand why that is. I assumed when it was still lit that it got it's power from a completely different source. The "other lamps", was only the SPK A lamp in this case (I had no high/low filters or loud running), and yes, it did go out with the dial lamps. Very good! You know your "stuff". :thmbsp:

Thanks for the infomation on how to bypass the switch if needed, it is very clear and easy to understand. If I have to resort to that, I'm sure it will be no problem to do.

EchoWars said:

The 'foil' piece of the switch that makes and breaks contact takes a lot of abuse and gets burned up (there's a lot of current going through it).

I've disassembled a few of these switches and taken the 'foil' piece of the switch from a spare one and put them into the dimmer switch, and you're good to go for another 30 years.

Click to expand...

Hey there EW... Hell, if I could find a "spare one" I wouldn't need to rebuild this one. :lmao:

Could you possibly cut a piece of heavy duty foil to size and replace it that way? Or... are you saying that a lot of other switches have the same size/style of foil?

Here is one from a sx-550 that is disassembled.

It is a 2 section instead of a four section.

I don't know if the x3x (..., 636, 737, 838, 939, 1010) switches are the same.

markthefixer said:

Here is one from a sx-550 that is disassembled.

It is a 2 section instead of a four section.

I don't know of the x3x (..., 636, 737, 838, 939, 1010) switches are the same.

Click to expand...

Thanks Mark, nice picture.

Bob

rt426 said:

Hey there EW... Hell, if I could find a "spare one" I wouldn't need to rebuild this one. :lmao:

Could you possibly cut a piece of heavy duty foil to size and replace it that way? Or... are you saying that a lot of other switches have the same size/style of foil?

Click to expand...

Any spare switch of this style will do...I certainly didn't have a spare dimmer.

Mark has a good pic of the piece(s) you likely need.

EchoWars said:

Any spare switch of this style will do...I certainly didn't have a spare dimmer.

Mark has a good pic of the piece(s) you likely need.

Click to expand...

EW: Do you remember if the 1010's switches are ALPS? This one had ALPS molded in on the bottom of the body.

thanks again guys...

BTW, I finally got around to pulling the bottom panel off of the 1010 last night. The inside of the bottom panel was really nice, super clean with no residue or stains... just shiny black. The power board was real nice... clean and not scorched at all. Main Caps very tight with absolutely no sign of any leakage whatsoever. So that was good news!

markthefixer said:

EW: Do you remember if the 1010's switches are ALPS? This one had ALPS molded in on the bottom of the body.

Click to expand...

No...I do not recall. But they look (IIRC) just like the one you took pics of.

SX-1010 Dimmer Switch

Mark, even though you added your expertise to this thread over 3 years ago, it worked for me today. I picked up a 1010 for $25.00 from a garage sale and had the dimmer switch problem. Followed your instructions and now no more problem...A little difficult soldering so close to the tuning cord but all worked out and absolutely no smoke!

Thank again...long time no see

Tim from Jersey.

tsd71 said:

Mark, even though you added your expertise to this thread over 3 years ago, it worked for me today. I picked up a 1010 for $25.00 from a garage sale and had the dimmer switch problem. Followed your instructions and now no more problem...A little difficult soldering so close to the tuning cord but all worked out and absolutely no smoke!

Thank again...long time no see

Tim from Jersey.

Click to expand...

Glad to hear it...

I too have a low buck 1010 in the queue (my 1010, the "my stuff" queue), and I have hopes of using it to come up with two different fixes, one would be a switch fix (replacement actually, and sources of parts), the other would involve adding an additional relay inside of the 1010 to switch the actual lamp current and the relay would be rated to handle the current involved with the incandescent lamp loads for long term survival.

I HAVE done the relay thing to a SX-828, the relay is energized in "dim" with the default being bright on the Normally Closed contacts.

the switch fix would best work with a unit that had/will have a LED conversion

I am especially interested in the condition of the 1010 switch, and it's level of deterioration. The 828 had a different, smaller switch that got fried by the temperatures generated.

markthefixer said:

DANGER:
When shorting the switch in one position, if you switch to the OTHER POSITION, it will put a dead short across two transformer taps. That's a GUARANTEED FIRE !!! IT *** WILL *** LET OUT the magic smoke.
YES you can permanently select bright / dim BUT NOT AT THE SWITCH!!!!!!
THIS IS THE ONLY WAY to eliminate the fire hazard.

OK, hold onto your hat, this is going to get windy.......

There are two unrelated lighting circuits going through that poor switch.

One set of circuits uses 3 of the four sections of the switch connected together to try to share the load, they are carrying about THREE AMPS of current!!! The switch is powered by the blue (bright) and violet(dim) wires from the big power transformer, which are two different AC voltage taps on a transformer winding.

These lamps are:
the six 300 mA dial illumination lamps
the two 300 mA meter illumination lamps
the three speaker lamp indicators
the 50 mA dial pointer

and I suspect these are your main culprits.

BUT, there's ANOTHER LIGHTING CIRCUIT. IT is a DC circuit that is a rectified version of the violet wire from the transformer. And that last remaining fourth switch section is used to short across TWO additional series diodes. This means that if THAT switch section goes bad, you STILL have the DIM lights working, as the current can flow through the diodes that do the dimming, you just can't get the bright setting.

These lamps are:
(only one at a time) AM, FM, PHONO 1, PHONO 2, MIC, AUX
the stereo indicator lamp
and in a nasty little switching circuit which you should be able to ignore for now
the Low Filt, Hi Filt, AF Mute, Mono/Stereo and Loudness lamps.

So literally the bottom line is,
YES you can permanently select bright / dim
BUT switching to the OPPOSITE selection when there are shorts at the switch will put a dead short across those two transformer taps. YOU WILL HAVE A FIRE.

You CANNOT just pull a fuse to isolate the dim (violet) winding as that would cost you that other lighting section.

You must CUT and MOVE ONE WIRE, the AC lamp's feed AT THE BOARD'S connection, then on the other DC lighting circuit
a short across two other pins can be soldered in place.

You will see two groups of pins on the AWS-068 board, one group of four and one group of three.
Pin #4 can be identified from EITHER side, as the centermost pin of the group of four pins, and pin 5 is next to it opposite the gap.
Pins 2 & 3 are on the OTHER side of the gap, in the group of three.

You MUST DISCONNECT the wire going to PIN #4 of the AWS-068 board that the dimmer switch is mounted to, and connect it to pin #5 of the SAME board. There MUST be NO remaining connection to pin 4, a "shortcut" of tying pins 4 and 5 together IS WHAT CAUSES THE FIRE...

Then for the other lighting circuit, you CAN put a short across pin #2 and pin #3. It will probably be easier to reach, than trying to get at the actual switch's soldered connections on the pc board.

Click to expand...

Mark, I used this method on my SX-1010, I now have an SX-828 with the same problem, the switch board is laid out a little differently showing only 6 pins instead of 7 on the 1010...how do I go about using this method on the 828, these switches are annoying...I would like full illumination 24/7

Thank you

tsd71 said:

Mark, I used this method on my SX-1010, I now have an SX-828 with the same problem, the switch board is laid out a little differently showing only 6 pins instead of 7 on the 1010...how do I go about using this method on the 828, these switches are annoying...I would like full illumination 24/7

Thank you

Click to expand...

answered in the correct thread...

markthefixer said:

I answered this very question yesterday:

It IS a SX-828 thread.

Noodle said:

Thanks again mark, steve and larry.

mtf, could you point me in the way of hard-wiring the dimmer switch to be BRIGHT all the time? is it as simple as unhooking the dim side and insulating that wire to avoid a short?


And if you could explain this difference. I always like to ask the eternal question, "why?"
On the 120V American/Canadian model there is a 2.2M 1/2W resistor connectd to the chassis from one side of the power cord, and the export models there's no resistor. Why?

Click to expand...

markthefixer said:

The schematic is not clear whether pin 1 or pin 3 is the high transformer lighting tap on the AWS-017 board with the lighting switch.

Pin 2 is the feed for the lights

Either pin 1 and pin 2 are connected together, or pin 2 and pin 3 are connected together for bright, AND you MUST DISCONNECT AND INSULATE THE UNUSED PIN 1 OR 3. Failure to do so will leave a shorting hazard that can damage the transformer and perhaps cause a fire.

as for the resistor - It's the LAW... longer explanations will have to wait. You should have noticed I am not posting a lot online for the last few weeks and that will continue into the middle of march. I neglected real-world things to do the AK postings, and now it's coming back to bite me in the a## big time, leaving me with little time for my usual of explanations...

Click to expand...

Click to expand...

Started another thread....

Mark, I applied the patch that you suggested to my 1010 with the same issue. Now the lights do work in dim mode but if I release the dim switch it triggers the protection relay. Any idea?
Thanks

bright is the blue transformer wire ( blue wire > awr-063 pin 3, then through F1 (3a) and out awr-063 pin 14) which also feeds pin 12 of the awm-062 protection board as well as pin 5 of the aws-068 switch assembly

dim is the violet transformer wire ( violet wire > awr-063 pin 4, then through F2 (3a) and out awr-063 pin 13) which feeds pin 5 of the awr-054 power supply as well as pin 1 of the aws-068 switch assembly.

I say this because even when you followed directions exactly (and they MUST be EXACT) , somebody could have been mucking about in there long before you got it.

The switch should be COMPLETELY INOPERATIVE.

Verify the wiring is exactly per the schematic (or MAKE it so), also F1 (blue wires) is probably blown and somehow the AC from the violet wire is getting through.to pin 12 of the protection board due to wiring error(s).

DO NOT POST IN THIS THREAD, start your very own thread on this problem. I will NOT respond in this thread.

Also look at my signature line: Hiatus means A temporary gap, pause, break. I am on such a break, dealing with my Father's estate.

This is Hank Miller, in Las Animas, CO! I have done over 200 rebuilds, but only 4 or 5 SX-1010's. Never saw or had any issues with the dimmer switch until this current rebuild. Just wanted people like me to know this fix does work. As I had the face plate off, I also removed the dial face so I could remove dimmer switch circuit board. I had no lights throughout this process. This board was burnt and I repaired board, and I got some light function back, but on bright it would dim then go out. I unwrapped wire #4 and rewrapped it to pin 5. I then simply wrapped a jumper wire from pin 2 to 3. This transfers the straight 8vAC through the rectifying diodes and gives you your DC voltage for your bright lights. The switch is safely bypassed. Does not affect the FM muting function. So another rebuild finished! Rock On!