Oldie but Goodie

[himrockffan]

Looking for mind much greater than mine.

I am in search for an old amplifier in an old receiver. I figure if I can get the amp portion of this receiver working it could be a neat thing for me to continue using it. It is an old Nikko NR-815. It has two SanKen s-60w amps in which one, I believe is bad. I probably could not find an equal replacement. But I have found a s-100w which is on the same spec sheet. My question is, could anyone tell me if I could replace the 60's with the 100's without blowing anything up or without wasting a few good dollars on something that would not work in the first place. What I hope is, attached to this post is a spec sheet showing both of these amps. Would you ever put the 100's in place of the 60's is my question?

Thanks, RLH

 

[MikeMl]

I see no reason that you couldn't use the 100W version. The quiesent current might be a bit higher 50mA vs 40mA, but that shouldn't hurt anything...

 

[BeerBelly]

The pin-out is different.

 

[KeepItSimpleStupid]

Here is one of the 60W things: https://www.littlediode.com/components/search.php?mode=search&simple_search=Y&posted_data[by_title]=Y&posted_data[by_shortdescr]=Y&posted_data[by_fulldescr]=Y&posted_data[by_sku]=Y&posted_data[including]=all&substring=S-60W&search_redirect=Y

Not cheap.

 

[dr pepper]

I have half a dozen or so sanken amp modules in my salvage bin, do you want me to have a look?

 

[himrockffan]

That would be great dr pepper. Thanks. What about you? Do you think a 100 could be used in place of the 60? I just wonder if the supply voltage in my current receiver would be enough to drive the amp. I wouldn't want to be stuck with something I'd never use.

I'll keep a look out for your response. Thanx!

RLH

 

[KeepItSimpleStupid]

My take: If you have a +-50 V supply, then yes provided you re-route the pin numbers.

If you have a +-40 V supply, then probably not.

 

[himrockffan]

Thanks KeepItSimpleStupid. Yes, I'll need to check that out. See what that E is. I'm thinking since there are 60s in there, the supply will only be enough for them. But if it is pushing 50 maybe it could work. But then again even if it did would the surrounding circuitry be able to provide the extra current the 100 will require to take advantage of its extra power? Or is that even an issue?

What do mean about "re-routing pin numbers"?

RLH

 

[KeepItSimpleStupid]

Compare the pin numbers of the 60 and 100 to what they are connected to. They don't match up.

Look closely at the spec sheet. At 50 V they both will work, although I'm never too happy when one channel is different. If you replace a single tweeter with an unidentical one, the system may sound different.

Having a 100 W and a 60 W amp may throw off the balance control.

BTW: KISS works as a substitute for the long name.

 

[himrockffan]

Yeah, if I should try a 100 I certainly will get two(one for each side). I must be missing something. BeerBelly must have been talking about the same thing as far as pin outs. I guess I don't understand what you guys are talking about. The schematics are nearly identical, but the pin numbers are different. Are you saying because of that they couldn't be interchangable even though schematically they appear the same?

Well, now that I think about it, I think I see what you guys are talking about. The pin arrangement might be identical but what each pin has on them must be different? They both must have 7 pins and would mount and connect to the CB in the same way but you are saying that each or some of their pin values are different. I find it curious that the 60 is numbered 1-7 but the 100 is numbered 2, 3, 4, 5, 7, 8, 9 (no pin 1 or pin 6). So I'm not quite sure how to interpret that. I guess I would have to have both to ohm out each for comparison. Right now I have not even removed either 60s. I am just assuming one is bad. I guess I should at least switch them and see if the problem switches to the other side or at least remove both and ohm each one out to see if they are same. At least that way I would be more knowledgable about what to expect the ohm readings of a good component to be. Right?

RLH

 

[dr pepper]

Ok then I'm at work now I'll have a look in the salvage bin back home in the morning.

100s might well work even with a lower volatge supply, its gonna be a heck of a job with the pins though, you'd need to bend most of them up and solder flying leads back to the board, ugly.

 

[Nigel Goodwin]

Ok then I'm at work now I'll have a look in the salvage bin back home in the morning.

100s might well work even with a lower volatge supply, its gonna be a heck of a job with the pins though, you'd need to bend most of them up and solder flying leads back to the board, ugly.

On the assumption that it 'might' work, the technique would probably be to mount it upside down, and run wires from the pins to the PCB.

However, as this thread says 'goodie' - it's not something I'd use for an amp which uses those nasty (and quickly obsolete) hybrid chips

 

[himrockffan]

My goodness, I didn't notice that there was a second page of replies! I bookmarked the first page and didn't notice there were more pages until I went back to the main page of the forum and saw that there were more replies so my apologies to mr. pepper and nigel.

Well, I have some good news. I took out the amps and started ohming them out, looking for differences between the two and low and behold I did notice a difference between pins 2 and 6... the input signal ... between the two. On the one in which came from the bad side it was intermittent. It appeared that when I pressed down harder on pin6 it leveled out. So I bent with my fingers up and down a couple of times and then I started getting a consistent ohm reading. With that I put them back in but switched sides. Both sides are back to full strength. I really do think that there was something with pin6 that was mechanically inteferring with the electrical signal. As old as these are it doesn't surprise me. When in doubt, jostle connections. It seems to so often come down to connections. I believe that was the problem here. So glad am not now tempted to try the 100's! From the different numbers on the pins, that could mean that the surrounding circuits for each of the 60s and 100s are different from each other, which sounds like what you guys had already determined. Figuring that out I think would have been above my head.

Thank you guys for trying to help and I'll be back asking for more, I can assure you. I was impressed by the responses I got.

Appreciate it!!

RLH

 

[dr pepper]

Well done.

I dug out my stk modules, I'm not sure which is what rating, ones a quad and 4 others are duals, but not req now.