Nivico 4210 Primary speaker jacks are unusual. Which is Positive?

[Ric Harris]

Saved a solid state relic from the recycling pile. It's ugly and needs some love but it works great. Has a bit of a reverb quality to the sound and has a real stereo separation. IDK it has a different flavor to the sound anyways.
My question is the primary speaker jacks are bit different. Had a Panasonic 44 series that had the same jacks but it had the original speakers with the male end on them. Nevertheless which is pos and which is com?
An what are those old jack called anyway?

 

[Ric Harris]

It's filthy and scuffed but I'll make it pretty again.

 

[cademan]

Take your pick. It really doesn't matter in your case except for phasing purposes. In other words, if your left speaker negative is the bottom hole in the speaker plug, then just make sure your right speaker's negative is also the bottom hole in the right speakers plug.

If you want to be proof positive, just take an ohm meter to the negative screw on the EXT speakers and see which hole is common.

Better yet, just remove the cover and see where the EXT speakers negative screw is connected to the main speaker hole.

 

[Tom B]

Use you meter to see which two connections are connected together, and to chassis common.If easier, take to top off, and see which connections are in common (connected from left to right.)
I would bet that the top are + and the bottom are common.

 

[Ric Harris]

I plan on opening it up in the next day or two so I can clean it up and begin repairs on the box. I am going to re-veneer it with a type mahogany African Makore. I've got a pair of Realistic cabinets done up already. I just need to decide on what 6 1/2" drivers to use. I am not sure what the WPC are on the JVC but my guess is in the 10-15 watt range. It's not easy to find quality low watt speakers in this day and age. I have some 3 watt Sony 6 1/2" as well as a pair of Pioneer 5 watt ones. I want 10 watt ones as I have some EAS 5 watt tweeters ready to go but I'm not finding much out there for low watt systems.

 

[KingBubba]

I've only seen one other Nivico. It was similar in nature and looked well made. I did not get it. I learned later that Nivico was the starting point for JVC.

 

[Ric Harris]

Nivico is just older branding for Victor of Japan aka JVC Japan Victor Corporation if memory serves. I considered them as grandpa's garage fair when I was a kid. Now I'm 53 and old enough to be one and I have a certain admiration for 60's solid state. I'm cleaning it currently as it looks to have been in grandpa's garage for about 40 years by thickness of the fuzzy gunk it's covered with. Once I clean it thoroughly I'll test it out again and then decide if I should replace a few of the ELNA caps. There's a few Nichicon caps in it that make me wonder if it was serviced at one time being that most of them large and small are ELNA's. The large silver one next to the transformer as well as the two largest ones toward the front are the ones I want to know if those are the key ones to replace.
Grunge of the highest order. YUCK!

 

[Ric Harris]

Nivico is just older branding for Victor of Japan aka JVC Japan Victor Corporation if memory serves. I considered them as grandpa's garage fair when I was a kid. Now I'm 53 and old enough to be one and I have a certain admiration for 60's solid state. I'm cleaning it currently as it looks to have been in grandpa's garage for about 40 years by thickness of the fuzzy gunk it's covered with. Once I clean it thoroughly I'll test it out again and then decide if I should replace a few of the ELNA caps. There's a few Nichicon caps in it that make me wonder if it was serviced at one time being that most of them large and small are ELNA's. The large silver one next to the transformer as well as the two largest ones toward the front are the ones I want to know if those are the key ones to replace.View attachment 901864 View attachment 901865 View attachment 901866
Grunge of the highest order. YUCK! View attachment 901867

By the way I am a novice at electronics repair. Speakers are my specialty. Mostly repair and restoration these days, don't build many anymore as I am not nearly as ambitious as I once was. Besides towers and home theater seems more the desires of most peeps not the 5 speaker w/15" woofer variety I used to build. In fact my last creation was some single speaker full range towers. Ah but I'm digressing. Anyhow this is fun to make the old Victor new again.

 

[analog]

That receiver was my first complete with matching speakers . I got it for Christmas somewhere in my teen years. As I remember it wasn't the be all end all but it sure made me happy. I would love to find another just because.