MCS amp. info. needed

djhurt1

New Member
I'm searching for a power transformer for an older component stereo amp. It's lasted 30+ years and I'd like to keep it going for nostalgia. Anyways It's an MCS 3842 amp distributed by JCPenny back in the day. The model is 683-3842. The part number of the transformer is SLT5M231. There's lots of references from Google but nothing is available sadly. I'm hoping someone here may have some information on either finding another replacement transformer or specifications so I can retrofit another one in there?
 
whew....transformers are tough, even on the mainstream stuff. Is this an NEC-built unit? If so, discover the NEC model number and better luck might be had...
 
Well, it was originally a Panasonic part. I did a quick search using something OTHER than Google (Yahoo, but there are other 'deep web' search engines that don't serve you the most popular hits or who paid the most...).

From the hits I saw at vendors, it is no longer made. If you could find any specs on it, either from the original MCS or JVC service manual for the amp, or from Panasonic, it might be possible to find a sub.

Here's someone who says they don't stock it but can deliver it in April. Good chance if you ordered it they would come back with 'no longer available', but you could give it a shot.

http://www.ued.net/ued/viewItemAction.do?itemCode=MSCSLT5M231
 
SLT is Matsushita

Most of whom had a thermal fuse on primary winding. Being American id imagine the set to Ve 120V only. Is there 3 pins on the primary side? If so 2 pins most likely have continuity. The thermal fuse pins are notable by the silver leads of the fuse, whereas primary winding one will be copper to terminal, other being copper attatched to thermal fuse....
 
I can't see much about the amp..... It looks auspiciously like the Technics SU-Z45

Is it based on STK2038 ?
 
Is that thermal fuse fixable/replaceable, and what would cause it to burn up in the first place? Presumably there is something else wrong with the amp.
 
I can't see much about the amp..... It looks auspiciously like the Technics SU-Z45

Is it based on STK2038 ?

It does in fact use the same transformer as the SU-Z45. But I'm having no luck under that brand either.

I have another post in another forum that shows alot of what's already been tried etc. Any issues posting a link to that in this forum?
 
Shouldn't be, people do it all the time. Just ebay links are prohibited outside the Dollars & Sense forum. We got no problem with collaboration!
 
Just curious, what led you to the conclusion that the transformer is dead. It is fairly rare to see this happen.
 
Just curious, what led you to the conclusion that the transformer is dead. It is fairly rare to see this happen.

I tested all of the secondary pins. No voltage at any of them. Primary pins all had voltage. I agree a very rare thing to happen.
 
From the hits I saw at vendors, it is no longer made. If you could find any specs on it, either from the original MCS or JVC service manual for the amp, or from Panasonic, it might be possible to find a sub.


The MCS 3840 & 3842 (1982-83) were the first Technics made integrateds for MCS. The specs were:

45 wpc from 20-20k hz with less than 0.05% THD.

It looks a lot like the Technics SU-Z45. I have the matching tuner, and it is a rebadged Technics ST-Z45, with a few cosmetic changes to the face.

They also sold a 3860 & 3862 - with identical looks - that had 60 wpc.

I've seen the owner's manual show up on ebay, but it included no schematic, or service manual, unfortunately.
 
Saw the pic of the Xfmr in that remote thread ... Bottom is primary

What resistance between pin 1-2 1-3 2-3 ?
 
Do not clean the face of MCS 3840 or matching components with alcohol. The print will wipe right off easier than the dirt. I don't care what anyone says, the Arvin Taiwan 3245 built units are better quality than most if not all of the Japan stuff. The sound from the 3840 is really dull compared to the 3245 on the same speakers, especially from the phono input. Had it hooked up to a Garrard GT35AP that sounded amazing on the MCS 3245 and Soundcraftsmen DX4100. This was immediately noticed by another person listening that doesn't even have good hearing....
 
Last edited:
I got the 3840 with a 3762 tuner. Looks great and specs are excellent, but real-life sound just isn't there. The brilliance of the sound is gone. Probably won't be buying another one when this one is gone. The tuner on the other hand picks up stations like the best of the best. Not sure how it sounds yet, haven't hooked it up to anything but the flat sounding 3840 amp. They are a compact size form-factor which is nice.
 
Do not clean the face of MCS 3840 or matching components with alcohol. The print will wipe right off easier than the dirt. I don't care what anyone says, the Arvin Taiwan 3245 built units are better quality than most if not all of the Japan stuff. Letters wipe right off and the inside of this thing looks like a mess compared to the 3245. What a joke...

I don't think you've found the "good" Japan stuff yet. The MCS integrated amps sourced from Matsushita were nothing to write home about. If you find one that still works, consider yourself lucky. Most either died from overheating, or had a power switch that failed. I have a handful of different models, and while they all sound fine through headphones, they also look like they could break if I look at them wrong. Fragile, almost flimsy construction. The NEC-made integrated amps were all well built, and very reliable. Those are the ones people love.
 
The MCS 2270 is no slouch... and would knock off some of the NECs off their pedestal

So I wouldn’t write off Matsushita...
 
Back
Top Bottom