Pioneer SX-1010, 939, 838, et.al., Relay Replacement

Didn't read the whole thread, did you? But...a few of the old plastic covers will fit a new relay, however, most will not.You didn't read the whole thread either. :) It isn't a simple hole...there's a lip that would have to be ground off to fit a socket (visible in the second pic). Simply using standoffs is by far the easiest solution, and requires no modification to the chassis (and takes a lot less time).


Read!!!.Nope.Guess it might help now and then..:scratch2:
I had just did it on a SX-1010..Swap the internals,that is.

I do like those flanged relays though.My "go to" relays when originals or proper PC mounts are not to be had.
 
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Friction fit?

Maybe a drop or two of epoxy would make for a more reliable mounting with these.
 
Friction fit?

Maybe a drop or two of epoxy would make for a more reliable mounting with these.

Thats what I was thinking as well. They don't cost much. I was looking for something similar only metal.
 
I'll have to order a few and see how they work. Looks like the dimensions are OK for the usual Omron's that I buy.
 
This thread is perfect. My sister has an sx 737 that she wanted me to try to fix. I'm pretty sure it is the relay that is bad, but you all clearly know more about these receivers than I do, so perhaps you can verify that for me.

The symptoms: The unit powers up fine, tunes fine, all controls work, but after being on for an undetermined amount of time, the relay clicks and the sound cuts out. Everything is still on and running and the tuner is tuning, but no sound. Then it may click back on, or it may not.

I put a voltmeter across the relay, and the voltage climbs up and dips down when the relay turns off.

So my thought is either the relay itself is bad, or whatever is sending the switching signal is bad... but I'm no EE major, so I can't seem to figure out what sends the on off signal to the relay.

Any ideas as to what I might need to replace?

Thanks so much!
 
This thread is perfect. My sister has an sx 737 that she wanted me to try to fix. I'm pretty sure it is the relay that is bad, but you all clearly know more about these receivers than I do, so perhaps you can verify that for me.

The symptoms: The unit powers up fine, tunes fine, all controls work, but after being on for an undetermined amount of time, the relay clicks and the sound cuts out. Everything is still on and running and the tuner is tuning, but no sound. Then it may click back on, or it may not.

I put a voltmeter across the relay, and the voltage climbs up and dips down when the relay turns off.

So my thought is either the relay itself is bad, or whatever is sending the switching signal is bad... but I'm no EE major, so I can't seem to figure out what sends the on off signal to the relay.

Any ideas as to what I might need to replace?

Thanks so much!

Yes, a transistor. BUT please PLEASE don't clutter up this thread with off thread topics, instead you are entirely welcome to and URGED TO start your own thread. quote your posts contents in it and I will be along to elaborate.
 
Echo. I installed a LY2F-DC24 in my SX-939. I swapped the covers (had to figure which side fit better as it's a bit tight either way) but it worked, new relay in old cover. Didn't use any standoff's for mounting as the original cover had the mounting ears at the bottom.

Larry
 
Pioneer receiver replacement relay reference guide

edit: note - this pertains to mounting the relay on a printed circuit board with appropriate pad contacts.
the MY series relays have the PCB PIN coil connections in a line with the contact connections
the LY series relays have WIDER pcb pin coil connection spacing than the contact connections!!!
Thus unless special provisions are made for the wider coil connections, the MYx-02 and LYx-0 won't interchange

condensed version:
----------start of: There aren't any relays in these models----------
models:
SX-424, SX-525, SX-626
SX-434, SX-535, SX-636
SX-450, SX-550, xxxxxxx
!!!!!!!!!!, SX-580, SX-680
or looking at it sideways, SAME models:
SX-424, SX-434, SX-450, !!!!!!!!!!
SX-525, SX-535, SX-550, SX-580
SX-626, SX-636, xxxxxxx, SX-680

!!!!!!!!!! = no such model
xxxxxxx = has a pc board mounted relay

----------end of: There aren't any relays in these models----------

----------start of: these models use ONE chassis mounted protection relay:------------------

models:
SX-727 SX-737 xxxxxxx
SX-828 SX-838 SX-850
!!!!!!!!!! SX-939 SX-950
!!!!!!!!!! SX-1010


dpdt chassis mount using upper ears 24v 653-LY2F-DC24 MOUSER.COM stock level 51 @ $ 6.55

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
to mount this relay use standoffs (mouser.com parts numbers) 15mm M-F aluminum,
need two per side for 30mm: 728-FM2110-3005-A due to the ears being on TOP instead of on the bottom!!


stainless preferred standoff from mouser 15mm (need two per side): 728-FM2110-3005-SS
728-FM2110-3005-A is 4.5mm od 3mm x 0.5 thread 15mm male female aluminum 0.63 /100: 0.43
728-FM2110-3005-SS is 4.5mm od 3mm x 0.5 thread 15mm male female stainless steel 1.07 /100: 0.74
728-FM1262-3005-A is 4.5mm od 3mm x 0.5 thread 15mm female female aluminum 0.59 /100: 0.40
728-FM1262-3005-SS is 4.5mm od 3mm x 0.5 thread 15mm female female stainless steel 0.97 /100: 0.67
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
----------end of: these models use ONE chassis mounted protection relay:------------------

----------start of: these models use ONE PCB mount protection relay per unit:------------------

SX-650
SX-750
SA-7800
4pdt pcb mount 24v 653-MY4-02-DC24 MOUSER.COM stock level 82 @ $7.24

SX-980 (for protect) DPDT pcb mount 653-my2-02-dc48

SX-780
SX-880
SX-1050
(the SX-1050 is a rare use of this particular relay,
but because it has a second chassis mount soft start relay
it is listed twice, once in this post, because only 3 models use it.)
4pdt pcb mount 48v 653-MY4-02-DC48 MOUSER.COM stock level 38 @ $8.11


----------end of: these models use ONE PCB mount protection relay per unit:------------------



--------- start of: these models have TWO relays each ---------------------------

---------------------------start of SX- x50 model series-------------------------------------------------

SX-1050 #1: asr-20 protect relay pcb mount 48 v 653-MY4-02-DC48 (pcb mount pins)
SX-1050 #2: asr-015 soft start relay chassis mounted 653-LY1F-DC48 (solder tabs)
why is this soft start relay different than the original? answer:
a visual chassis inspection reveals a dpdt and that WOULD be a type ly2f relay that uses 48v, which doesn't exist,
there IS a ly2f type relay available, BUT it's available ONLY in a 24v coil!!
luckily 24v is available on awr-104 board if you want to convert it to the 24v, using the 653-LY2F-DC24
otherwise the ly1f type is available in both 24v or 48v (why convert to 24v when a 48v is available?)
all 3 (653-LY1F-DC48, 653-LY1F-DC24, 653-LY2F-DC24) are stocked in 40+ quan under $7.00


SX-1250 #1: asr-10 protect relay pcb mount 24 v 653-MY4-02-DC24
SX-1250 #2: asr-015 soft start relay chassis mounted use 653-LY1F-DC48
why is this soft start relay different than the original? answer:
a visual chassis inspection reveals a dpdt and that WOULD be a type ly2f relay that uses 48v, which doesn't exist,
there IS a ly2f type relay available, BUT it's available ONLY in a 24v coil!!
luckily 24v is available on awr-107 board if you want to convert it to the 24v, using the 653-LY2F-DC24
otherwise the ly1f type is available in both 24v or 48v (why convert to 24v when a 48v is available?)
all 3 (653-LY1F-DC48, 653-LY1F-DC24, 653-LY2F-DC24) are stocked in 40+ quan under $7.00

------------------------------end of SX- x50 model series ----------------------------------------------
------------------------------start of SX- x80 model series ---------------------------------------------
start of convenient but confusing rehash:
SX-580 has no relay
SX-680 has no relay
SX-780 (for protect) 4pdt pcb mount 653-my4-02-dc48
SX-880 (for protect) 4pdt pcb mount 653-my4-02-dc48
SX-980 (for protect) DPDT pcb mount 653-my2-02-dc48
end of convenient but confusing rehash.


The sx-1080, SX-1280 & SX-1980 each use two relays, both are PC board mounted:

note #1:
these last three models (1080,1280,1980) use the same PCB mount soft start relay: 653-LY1-0-DC48 (hmmm: 4/20/16 edit: look for LY1F-DC48??)
this is the preferred relay if you can find it,
otherwise use a 653-ly1-0-dc24 and modify circuitry to run on 24v
this is possible on the sx-1080 and sx-1980 BUT NOT on the 1280,
because I suspect the 1280's 24v supply is weak.

note #2:
these last three models (1080,1280,1980) use the same PCB mount protect relay: 653-my2-02-dc48

thus:
x80 models that have two relays, one protect, one soft start:

SX-1080 #1 (for protect) DPDT pcb mount 653-my2-02-dc48
SX-1080 #2 (soft start) 653-LY1-0-DC48, (4/20/16 edit: LY1F-DC48??)
the pcb pattern will NOT support adapting in a 48v LY2 type relay.!!!
if 653-LY1-0-DC48 not available, there's 24v @ plenty of current available at AWR-152 C23 + for a 653-LY1-0-DC24,
remove AWM-120 R12 (2.2k 2w) and run a wire from the pad/hole connected to the relay through the chassis to AWR-152 C23 +

-------
SX-1280 #1 (for protect) DPDT pcb mount 653-my2-02-dc48
SX-1280 #2 (soft start) LY1-0-DC48 (4/20/16 edit: LY1F-DC48??) note there is NO mouser.com 653- prefix!! this is a rare relay) so use: 653-LY2-0-DC48
the pcb pattern WILL support an LY2 relay, and my board was factory drilled for it.

(it's better to use a 48v relay here, as the the 24v power supply is made by a "doubler",
and the 24v (653-ly1-0-dc24 & 653-ly2-0-dc24) relays MIGHT be too much of a load for the doubler circuit)
edit; you CAN use 24v relays by changing the sx-1280's AWR-157 R22, from 2.2k @2 Watts recalculates to 1.7k and 3+ watts
BUT you will be pulling 3.2 watts (instead of 1.6 watts ) from the power supply and throwing away 2.3 watts (instead of 0.8 watt) as heat in the new resistor.

-------
SX-1980 (for protect) DPDT pcb mount 653-my2-02-dc48
SX-1980 (soft start) 653-LY1-0-DC48 (4/20/16 edit: LY1F-DC48??)
if not available, there's 24v @ plenty of current available for a 653-LY1-0-DC24
the pcb pattern will NOT support adapting in a 48v LY2 type relay.
ALSO: WATCH YOUR HEIGHT - THE TOP OF THE RELAY IS VERY CLOSE TO THE BOTTOM COVER!!


------------------------------end of SX- x80 series ---------------------------------------------

--------- end of: these models have TWO relays each ---------------------------

Some of the protection relays in higher power units had factory mounted magnets on the outside case near the contacts
This was to suppress DC plasma arcs when interrupting 30v + DC faults.
I have removed the magnets from the old tape (good stuff - high quality and still lasts) and superglued them to the new cases.
Tape (most modern tape) generally gets gooey after a few years, unless specially formulated (and expensive - like kapton tape)
I NEVER use any tape for "permanent" fixes.

and as a LAST resort when having to replace a chassis mount relay that formerly had ears (The "F" in the part number),
with a more generally available relay WITHOUT ear type mounts, I use two angle brackets attached to the relay sides by superglue.
(the LYxF type relays listed in this post have the "ears" for the chassis mount.)
A "secret": superglue has lousy shear (twist) strength - so make SURE that the angle brackets are properly positioned,
otherwise when tightening down the second bracket - the misalignment will translate to shear force and POP OFF!! (lol)....
(LY1F-DC48??)


edit LY 4F removed, LY2F works.
 
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Thanks for posting that relay info, Mark! I'm going to print it out and put it in my notebook. :thmbsp:

As an aside, is there any way to design a solid state replacement for these trouble prone relays? :scratch2:
 
They are NOT trouble prone. They do their job, and if folks don't turn down the volume before turning off the unit, there will be arcing as the contacts are opened. Same with switches. There is mechanical wear too. 20 to 30 years isn't bad...

Gold contacts ( little corrosion) are nice, but there are current density considerations, as well as the fact that gold is SOFT, and WEARS... it's good for infrequently operated mechanical small signal switches, and things like plug in PC board connectors.

DC solid state relays? Can't beat the reliability of opening contacts in a fail-SAFE situation. Transistors or Mosfets have to get in the way of the signal...

Failures in the circuit are more towards the design side, of the coil driver circuitry, with inductive kick back when turning off and inadequate heat sinking of the not so robust transistors passing the relay coil's current.
 
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First, just wanted to thank for the useful thread. The LY DPDT relays are still available from Amazon, which is great.

Second, I have a question. I have SX-838 with blown left channel. DC offset on the channel slowly rises from 0V to -13V, and obviously at one point the protection relay shuts down the amplifier section.

My question is what is the easiest way to remove the amplifier board from the receiver? There are two bolts, but it looks like there are wires on each side of the board that would not let me turn the board to solder on it. Do you desolder wires that go to output transistors? Or do you have to disconnect all wires?

Thank you!
 
First, just wanted to thank for the useful thread. The LY DPDT relays are still available from Amazon, which is great.

Second, I have a question. I have SX-838 with blown left channel. DC offset on the channel slowly rises from 0V to -13V, and obviously at one point the protection relay shuts down the amplifier section.

My question is what is the easiest way to remove the amplifier board from the receiver? There are two bolts, but it looks like there are wires on each side of the board that would not let me turn the board to solder on it. Do you desolder wires that go to output transistors? Or do you have to disconnect all wires?

Thank you!

This is way off subject, you are HIGHLY encouraged to PLEASE start your very own repair thread.
 
having read this thread and identified the OMRON MY4-02DC24 as the replacement, I found I had one. I then removed the case of the original and the new one, and found that the old case very "nearly" fits on the new base, however there is about an extra 0.5mm on the new OMRON base.

I then used a very fine file to file down the OMRON plastic base (being careful so as to not get any plastic filings in the relay mechanism) on the opposite side to the metal frame, removing the small rectangular section at the base, and hey presto, it fits very snuggly into the original case held by the lugs at the side.

The result, is a a new OMRON relay mechanism in the original case with no mounting adjustments, and all works very well.

As has been pointed out this may not work for all relays, but is worth looking into for the convenience
 
It has taken a year since Avionic's post, but I finally have a real need for one of these. I have a Pioneer quad that uses a MY4-style relay that cannot be replaced with an LY2-style, and I know of no source for an MY4 with a flange.

Got a couple on the way from Mouser. We'll see how they fit.

A little bit of a thread bump, but I just recently had a SA-8100 that used a MY4 with the flanges and wanted to share my success story with using the relay flange adaptor (528-16-782C1) with a 653-MY4-DC24 (with the plug in terminals). The original case had been broken pretty badly by something and it was haphazardly taped onto the chassis. I could not replace it with a LY2 due to the fact it uses one of the contacts to switch on and off the protection lamp. So, I ordered the MY4 relay and the adaptor. I first tried to see if the adaptor would fit without modding it, but it was clear that it would not fit through the chassis hole for the relay.

I then got a brainstorm and cut off the little tabs on either side flush with the main part of the adaptor, then centered it and loosely tightened the screws so it would hold it in place on the chassis but still move a little. Then, I put the relay down through the chassis hole into the socket and centered it up with the chassis hole using the relay. After that, I tightened the screws evenly on both sides and just as I had hoped, the socket flexed, tightening it around the relay and held it firmly in place. I could not pull it out unless I pulled hard enough I thought I might break the socket or the relay case, even then it only budged a little. All in all a easy mod, only took me 15 minutes. Some photos of the fit and the modded socket:

mbP26RD.jpg


p1y1WCM.jpg


9ODvwms.jpg
 
Pretty sure I did something similar, though I might have used a few drops of epoxy to make sure it all stayed in place.
 
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