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

Hi

In the, what seems to be a, never ending process, of restoring my SX-1080, I'm about to replace the 2 relays on the AWM-120 protection board.

As MTF has mentioned in post #30 http://audiokarma.org/forums/index....-relay-replacement.150439/page-2#post-6759577, a replacement for the speaker protection is mouser part# 653-MY2-02-DC48, which is in stock.

When it comes to the soft start relay, the mouser part is 653-LY1-0-DC48, but since it isn't available I have the choice to either:

replace 2.2 K Ohm R12 with a 1.7 K Ohm +3 watt and use the 24 Volt version 653-LY1-0-DC24​
or
use the 653-LY1F-DC48.​

If the only difference between 653-LY1-0-DC48 (unavailable) and 653-LY1F-DC48 is the flanged cover, I would think that 653-LY1F-DC48 is the better choice?

From photos from the net it looks like I must be prepared to file down the width og the pins, to make them fit the mounting holes - is this correct?

When I look at the drawing on the data sheet for the MY it shows 8 pins, but only 6 pins can be seen on the schematic in the service manual. How do I treat this difference - is it self explanatory, once I have the MY2-02-DC48 in hand?

Thanks
Ole
 
After this answer, any further discussion should be directed at a new thread dedicated to the problem.
BUT this has led to some improvements and clarifications in my big post #30 of this thread.


The easier question first:
protect relay MY2-02-DC48 - just clip the two pins that don't line up with the PCB holes.

the other, the soft start relay is a toss up, BUT you misread the post - the resistor thing was intended only for the sx-1280
either:
1. use the 653-LY1-0-DC24 relay that HAS the correct pins for the pc board mount, tap 24v from another board
or
2. use the possibly too tall flanged 48v relay 653-LY1F-DC48, but it's PINS are too wide for the holes provided - and the pins may just have holes in the center that make "narrowing them down" problematic.

I have in the past when forced to use wider pin relays, taken a dremel tool and 1/32 inch (0.031" , or 1mm will do) drill bit and changed the pc board holes to slots.
but this was NOT in an sx-1080, YOU will have to worry about adequate clearance between the top of the relay and the bottom plate when both the pc board and bottom plates are mounted. The Flanged relay may be too tall - you will have to measure the clearances on your unit and decide if there is enough room.
YOU have to decide if your hand is steady enough to turn four holes into slots - as opposed to removing a resistor and adding a wire.

The SX-1080 relay power (BOTH relays!!) is drawn from the regulated DC supply's raw DC source that is already pretty loaded, and the magnitude of the doubled load (37mA to pull in a 24v relay coil versus 18.5mA to pull in a 48v relay coil) caused by using a lower resistance to operate a 24v relay from it may induce problems, while the tapped raw 24v supply should shrug off the increase.

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 +
 
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After this answer, any further discussion should be directed at a new thread dedicated to the problem.
BUT this has led to some improvements and clarifications in my big post #30 of this thread.

The easier question first:
protect relay MY2-02-DC48 - just clip the two pins that don't line up with the PCB holes.
:thumbsup:

the other, the soft start relay is a toss up, BUT you misread the post - the resistor thing was intended only for the sx-1280
either:
1. use the 653-LY1-0-DC24 relay that HAS the correct pins for the pc board mount, tap 24v from another board
or
2. use the possibly too tall flanged 48v relay 653-LY1F-DC48, but it's PINS are too wide for the holes provided - and the pins may just have holes in the center that make "narrowing them down" problematic.
Yes, I see now that I mixed the 24 volt solutions.

I have in the past when forced to use wider pin relays, taken a dremel tool and 1/32 inch (0.031" , or 1mm will do) drill bit and changed the pc board holes to slots.
but this was NOT in an sx-1080, YOU will have to worry about adequate clearance between the top of the relay and the bottom plate when both the pc board and bottom plates are mounted. The Flanged relay may be too tall - you will have to measure the clearances on your unit and decide if there is enough room.
YOU have to decide if your hand is steady enough to turn four holes into slots - as opposed to removing a resistor and adding a wire.

The SX-1080 relay power (BOTH relays!!) is drawn from the regulated DC supply's raw DC source that is already pretty loaded, and the magnitude of the doubled load (37mA to pull in a 24v relay coil versus 18.5mA to pull in a 48v relay coil) caused by using a lower resistance to operate a 24v relay from it may induce problems, while the tapped raw 24v supply should shrug off the increase.
Well, I find your option 1. to be the optimum solution; the relay will fit (after clipping the unused pins), won't need to modify the pc board, very easy to remove R12 and draw a wire from the 24 volt at the positive pin on C23 on AWR-152.

Thanks, Mark :thumbsup:, and also credits to EchoWars for pointing out, that worn relays also can induce poor sound.
http://audiokarma.org/forums/index.php?threads/sx-1080-no-soft-start-instant-on.723102/#post-9757841

If the new relays doesn't help on the muffled sound I get, I'll dig in on the power supply, which is in a very worn state (in another thread!)

I'll just repeat your call for stopping this thread, and start a new.

After this answer, any further discussion should be directed at a new thread dedicated to the problem.
 
"----------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

4pdt chassis mount using upper ears 24v 653-LY4F-DC24 MOUSER.COM stock level 14 @ $11.61
or a substitute:
dpdt chassis mount using upper ears 24v 653-LY2F-DC24 MOUSER.COM stock level 51 @ $ 6.55

being chassis mount, conversion from double connected 4pdt to dpdt contacts is easy


I ordered the 653-LY4F-DC24 relay from Mouser as shown above for my SX-737, it came as a much larger relay than the Omron one that came in the unit. The tabs on this replacement part are at the top on opposite corners in stead of in-line. I can't see any way of mounting it in the original location. :( I assume it's been superseded to the larger body???

I read where Mark said that the DPST 10 amp 24V relay would work. Not wanting to wait or pay shipping for another one from Mouser, I went over to the local Fry's and bought a NTE R14-11010-24, about $8. It's a properly sized DPDT 10 amp, 24 volt relay. It does not have mounting tabs, but the guts from the new one fit perfectly inside the original OMRON clear plastic case with no trimming. The original relay was 4PDT but with the pins bridged, so it actually simplified the wiring while installing it.

Hope this helps!
 
Marty; When i did mine I ordered the 24v 653-LY4F-DC24 for both the 737 and 939. The new guts dropped right in the old case with a little bit of tightness but that was it. No interference from the casing at all and it fit as original. Sure sounds like they went to a larger body, or Mouser sent you the wrong part?
 
Here's what I got from Mouser along with the packaging for the relay from NTE,(The old Omron guts are inside the NTE clear cover)


Here's the original 4PDT relay showing the bridged pins:


Here's the new DPDT 10 amp relay in place:
 
Stupid Photobucket changed their third party image posting policy:thumbsdown:

To see the pictures I posted above, right click and select Open in a new tab to see them. Hope you have a good pop-up blocker because Photobucket has a lot of them!:(
 
Well, I should have caught this sooner. Marty Socal blazed the trail in June 2017

The LY 4F footprint is INDEED too large to use now. The posted list has been adjusted.
 
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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

This is an older thread, but still helpful. Thanks mattsd.
I bought the same flange adapter and modded it the same way, for use on my SX-850.
I used washers under the flanges to keep it from bowing when tightened, and used a small amount of glue to secure the adapter to the new relay.

upload_2018-7-4_13-21-43.png

upload_2018-7-4_13-22-21.png
 
This is an older thread, but still helpful. Thanks mattsd.
I bought the same flange adapter and modded it the same way, for use on my SX-850.
I used washers under the flanges to keep it from bowing when tightened, and used a small amount of glue to secure the adapter to the new relay.

I bought the relay and the stand offs, only to realize once they arrived that I could just mount the relay on the opposite side of the chassis and (sx-850) and not needed to buy the stand offs.
 
I went with Glenn's method using standoffs to replace the protection relay on my SA-9900. I used a Panasonic HL2-HTM-DC48V-F 48V relay which appears to be nearly identical to the Omron LY2F-DC48.

P8220078.JPG
 
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Okay, let me confirm I understand this correctly. I have an SX-850 that is going to get the now ubiquitous 653-LY2F-DC24, the same type I used in a couple of 737s and a 727. In those cases I reused the shell of the old relay so it would fit in the original position. Can I do the same for the SX-850 or do I need to use the new shell along with some extra hardware/positioning?

I also have an SX-1050 that I'm restoring, which I come to read here that it has TWO relays, one for protection and one for soft start and both are unlike any other Pioneer, being 48v. The protection relay is a PCB pin type mounting, the soft start is the more common "ears" type, and neither is available as a direct fit replacement.

Is that correct?

Feels like I should leave the 1050 alone unless I experience a relay problem?
 
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