Snubber (or Arc Suppressor Network?) value significance in receiver power switch

[pumablues]

Hi all!

I'll try to keep this to the point.

I'm replacing an ALPS toggle power switch in a Sony STR-6055.

The old switch (which broke in shipping) had a snubber (or I've heard some call them arc suppressor networks) soldered onto two of the switch contacts.

The component is orange, branded "NCC", and has these values on the side:
PSR
.033 + 120 ohm
500V
03 0

I've attached a photo as well.

My questions are as follows:

1) Should/can I just re-use this old component, or given that I'm replacing the switch, should I replace it outright?

2) If I need to replace it, I'm having a hell of a time finding an exact match. How much wiggle room in those values do I have?

For example, I've found one near match that is out of stock, with these values:
.033uf
120 ohms
250 vac

or I've found this Kemet: https://www.mouser.com/ProductDetail/KEMET/PMR210MB5330M100R30?qs=ffqAhwBssBv78vSR4Bl5Bg==
with the correct .033uf, but only 100ohms (i think??), and 250VAC (600VDC)

And finally, this C-D "quencharc" units, and the smallest uf they offer is:
0.1uf
100ohms
250vac (600vdc)
https://www.mouser.com/ProductDetail/Cornell-Dubilier-CDE/104M06QC100?qs=N93jU/OIph6DEMraSx0M3A==

I'm totally lost on how best to deal with this part. Any help you can provide would be very much appreciated, because replacing this switch has been a weeks long affair and I just want to get it done now

 

[pumablues]

Oh, and question 3 -- could I just make my OWN snubber RC, with a .033 uf capacitor of some kind and a 120ohm resistor in parallel?

 

[elnaldo]

The RC are in series. Search for "snubber rc network"



You could use the old part if you don't damage it while desoldering.

You can make your own part. Many old amps come this way. The capacitor should hold the AC mains since it will be energized while the amp is OFF. The resistor should hold some watts too.

250VAC is ok

A few ohm shouldn't make a difference in a mid sized amp. I can't tell about very large amps with very powerful transformers. But most small amps have just the capacitor without any resistor.

 

[gadget73]

I would go with an X rated safety cap for this job. Or an XY rated will also work just fine. X is for across the line, Y is line to chassis. With the switch in the off position, the cap would effectively be across the power line.

 

[50 Green]

No need to replace it unless you've damaged it somehow. Just reuse it with the new switch.

 

[pumablues]

I did damage it, after all that I cut the leafs too short when removing from the old switch -- and then, when trying bto position for the new switch, one lead snapped clean off at the base.


So...I need to buy a replacement now. I think I found a suitable one:
.033uf, 120ohms, but only 250V.

It sounds that should work fine, though, from everyone's helpful comments above.

Once I get it, does it matter how I orient it as long as it's connecting to the same contacts as the original?

Or us there a "correct" orientation that I need to be aware of?

Also -- last question -- if I needed to replace with a different value, could I go up in uf, from .033 to .046 or even .1

Thanks all, very much!

 

[elnaldo]

It doesn't have an "orientation", any way is the same.

Don't worry about the 250V. The old part is probably rated for 500VDC and the new part probably 250VAC.

If 0.033 is not available I'd go with 0.022 or 0.047. Larger caps allow more AC current flow when the unit is off. Not too much, but I'd stay around the original value.

 

[pumablues]

Thank you @elnaldo !!

 

[pumablues]

If anyone stumbles across this in the future, here is the part I ordered, and who I ordered it from:
https://www.tme.com/us/en-us/details/re120033/tht-suppression-filters/roxburgh-emc/

Roxburgh EMC RE120033 (seems to be re-branded Okaya maybe?)
Filter: RC; 0.033uF; THT; 16x13.5x6mm; Pitch: 14mm; Capacitor: X2

Specs: 0.033uf, 120ohms, 275V AC, x2 capacitor

I ordered this to replace a broken snubber cap (aka, arc suppressor, aka RC Filter / Network) in a Sony STR-6055 receiver that I'm trying to repair.

I ordered my part from TME, which is an EU based company (headquartered/started in Poland, I think), but shipping seems to be only about $10 USD for the small parts I ordered. The ordering process was definitely bit different, likely because the better restrictions on online sales and data gathering/selling in the EU.

Mouser and Digi-Key did not have close to exact replacements for me; Newark had this same unit on its site, but listed as backordered for many months. Parts like this just did not seem to be well stocked in the US. So, TME it was.

I ordered 10, so in case I break one, or find another receiver that needs a similar snubber cap, I'm all set. I can also offer a few as replacements, this way, to other AK'ers through Bartertown or whatever.

Thanks again for your help, all. Especially to @elnaldo for all the technical responses. Cheers!

 

[boke]

Maybe this might help :

https://www.digikey.ca/en/products/detail/kemet/P410QS333M300AH101/5272263

33nf == 0.033uf
100 ohm….close to 120 ohm

Should do the trick. And there’s still around 400 in stock. But at over 3 smackaroonies, they’re not cheap. Buy 10+ price drops to $2.50 .

Bought some to fix my Sony Str-6120 after I had to replace a defective (open/completely corroded, arc-ed out) spst switch….because…..the snubber was MIA.

 

[michael_w]

Well, here is another possibility for the Okaya AU1201 RC snubber (cap 20%, resistor 30%).
At $0.33 each (100 minimum plus $8.99 shipping as of December 2024), this seems to be a bargain option, especially since they look to be drop in.
https://www.onlinecomponents.com/en/productdetail/okaya-electric/au1201-12040263.html
I note that I've not ordered from onlinecomponets.
So far I've been making them by using a 0.1uF X2 cap (10%) in series with a 1W (5%) 120 resistor (for about the same price). It takes about 30 seconds to put one together though they don't look quite so professional.

 

[gadget73]

I guess if you go through a lot of them it makes sense but fair bet if I bought 100, after I kick the bucket someone will throw away 95 of them.