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rocks66ss
01-02-2010, 04:27 PM
One of the lugs is broken off of the rotary switch. Lug #6, the one the Red coil wire goes to. Is there anything special about this switch? Is it just a 2 pole three position switch?

Is there anywhere I can get these? Also while I have this crossover opened up it almost seems I should replace the caps. No where on them does it state what value they are rated. I know i need a 12uf, a 16.5uf, and a 13.5uf what VDC should they be rated at. I have the JBL part numbers, but can they even be found.

I found this forum by searching for parts. I've had these speakers for 31 years. D130's and Le175's and I bought them used then. I have never had to look for parts or components. It look like it might be tough to find them.

If anyone can offer up any advice on what to use, and where to find them. I would be most appreciative.

Thanks.

Rocky

BMWCCA
01-02-2010, 04:58 PM
Welcome.

The "search" function is your friend: http://audioheritage.org/vbulletin/showthread.php?t=26874

I believe there was something quite recently on the switch, too. I'll let you look for a while. :)

rocks66ss
01-02-2010, 06:16 PM
I have used the search function extensively, maybe it's the combination of words I am using but I cannot find the information I am seeking on the the switch and where to find one, and the voltage values on the caps.

I had already found and printed off the Two different schematics in the link you provided me, thank you for it anyway. I am not well versed in interpreting them, hence the question about what type of switch, ie a 2 pole, and I guess it's quite obvious it's a 3 position switch.

Is this a special switch, or is it something I can pick up at an electronics store here in Kansas City. I'm capable of doing the work, I just want to insure I get the correct parts, as I would like to do this once,

Thanks

Rocky

BMWCCA
01-02-2010, 07:12 PM
Can't help with the specs and I'd have to guess if your electronic store has parts leftover from the '50s you may have a shot.

Using Google Advanced search netted this thread which might interest you:
http://www.audioheritage.org/vbulletin/showthread.php?p=263489

:dont-know

rocks66ss
01-03-2010, 05:40 AM
Well can anyone tell me what I can replace my rotary switch with??
If the part number and what type of switch it is now seems to be so specialized and elusive, somebody somewhere has to have replaced it with something!

I have spent a whole day yesterday trying to find an answer as to what I can replace this switch with, I can't imagine everyone who has a N1200 crossover who had a rotary switch go bad just go oh well and toss it in the can.


Rocky

BMWCCA
01-03-2010, 07:05 AM
Well can anyone tell me what I can replace my rotary switch with??
If the part number and what type of switch it is now seems to be so specialized and elusive, somebody somewhere has to have replaced it with something!

I have spent a whole day yesterday trying to find an answer as to what I can replace this switch with, I can't imagine everyone who has a N1200 crossover who had a rotary switch go bad just go oh well and toss it in the can.
You're missing a "lug". Is it repairable? Can you kluge around it with solder?

Maybe a picture would help with repairing what you've got. I'm not taking mine apart to find out. It's not really so unusual for a mechanical part from fifty-years (or more) ago to be unavailable. The deafening silence you're getting in response to your question might be because it's a holiday weekend, or just that no one's had to repair something like that. A picture would help since I'm curious how a part can get physically broken beyond repair on a switch sealed inside a box and subject to infrequent use. You could always pick a setting and hard-wire around it if it comes to that. The positions are 3dB steps. As they say on Ebay, "It doesn't affect the sound!"

There's always a used crossover on Ebay and the switch may fit other models such as the LX-1, but I'm no expert. I don't know which vintage yours is but there are four on Ebay right now.

:dont-know

Mannermusic
01-03-2010, 07:18 AM
Well can anyone tell me what I can replace my rotary switch with??
If the part number and what type of switch it is now seems to be so specialized and elusive, somebody somewhere has to have replaced it with something!

I have spent a whole day yesterday trying to find an answer as to what I can replace this switch with, I can't imagine everyone who has a N1200 crossover who had a rotary switch go bad just go oh well and toss it in the can.


Rocky

Hi Rocky,
I've had to refurb a pair of 3120s which are the later "pro" equivalent of the N1200 - same schematic. My 3120 schematic says 2 pole, 3 position, PN 10290 for the switch (12 solder lugs) and I wonder if it isn't a standard JBL part for their 3 position X-overs. If so, you could pirate one from any old JBL crossover with a 3 position switch - check the info on the schematics in the Tech Info section at the bottom of the web site intro page . . . you have to get into the pro audio "networks" section. But, I'd probably try to save the switch, resolder the lug? Perhaps you could jumper over to an unused lug or similar? Thinking out loud, here (dangerous!).

As far as the caps, I've used both Solen and Dayton metallized polypropylene which are rated at 400 VDC and 250 VDC respectively with excellent results (Parts Express has both) - parallel 'em together to get the values you want - the normal spec. is +/- 10%. There are some old time JBL engineering guys on the site who may chime in here to verify the above. Good luck - it's always satisfying to keep this old technology running! MM

rocks66ss
01-03-2010, 09:39 AM
You're missing a "lug". Is it repairable? Can you kluge around it with solder?

Maybe a picture would help with repairing what you've got. I'm not taking mine apart to find out. It's not really so unusual for a mechanical part from fifty-years (or more) ago to be unavailable. The deafening silence you're getting in response to your question might be because it's a holiday weekend, or just that no one's had to repair something like that. A picture would help since I'm curious how a part can get physically broken beyond repair on a switch sealed inside a box and subject to infrequent use. You could always pick a setting and hard-wire around it if it comes to that. The positions are 3dB steps. As they say on Ebay, "It doesn't affect the sound!"

There's always a used crossover on Ebay and the switch may fit other models such as the LX-1, but I'm no expert. I don't know which vintage yours is but there are four on Ebay right now.

:dont-know

As far as the lug goes, no it is not repairable. where the body of the switch is sandwiched and the lug comes out of the center, it is broken off flush. And as far as the configuration of the switch, I dont believe another lug can be utilized, but like I said, I have a hard time interpreting the schematic.
I am watching the auctions on ebay



Hi Rocky,
I've had to refurb a pair of 3120s which are the later "pro" equivalent of the N1200 - same schematic. My 3120 schematic says 2 pole, 3 position, PN 10290 for the switch (12 solder lugs) and I wonder if it isn't a standard JBL part for their 3 position X-overs. If so, you could pirate one from any old JBL crossover with a 3 position switch - check the info on the schematics in the Tech Info section at the bottom of the web site intro page . . . you have to get into the pro audio "networks" section. But, I'd probably try to save the switch, resolder the lug? Perhaps you could jumper over to an unused lug or similar? Thinking out loud, here (dangerous!).

As far as the caps, I've used both Solen and Dayton metallized polypropylene which are rated at 400 VDC and 250 VDC respectively with excellent results (Parts Express has both) - parallel 'em together to get the values you want - the normal spec. is +/- 10%. There are some old time JBL engineering guys on the site who may chime in here to verify the above. Good luck - it's always satisfying to keep this old technology running! MM

I will check that section on schematics. thanks for the info on the caps, I just didn't know what VDC they should be rated at. As far as re soldering to another lug, looks like that's not possible.

Thanks again for both of your time.


Rocky

BMWCCA
01-03-2010, 11:35 AM
As far as re soldering to another lug, looks like that's not possible.Aw, throw us a bone...err, photo...anyway so we can see for ourselves what you're talking about.

http://audioheritage.org/vbulletin/showthread.php?t=817

Beowulf57
01-04-2010, 05:57 AM
Any good quality 2P-3T switch will do. I replaced the switches in my LX5 networks years ago using sealed types: less likelihood that contact oxidation/corrosion requiring cleaning will develop. I didn't bother replacing the caps...but seem to recall I added small value bypass caps in the HF section for a little smoother treble.

rocks66ss
01-04-2010, 07:42 AM
Any good quality 2P-3T switch will do. I replaced the switches in my LX5 networks years ago using sealed types: less likelihood that contact oxidation/corrosion requiring cleaning will develop. I didn't bother replacing the caps...but seem to recall I added small value bypass caps in the HF section for a little smoother treble.


Thank you very much for your reply. I just couldn't imagine that the rotary switch was so proprietary that there wasn't something to replace it with.

I have the schematic so I assume that the numbering will be the same on the new 2P-3T switch? A direct swap? So everything that lands on it's prospective terminal will land on the same on the new switch?

I am going to fix this crossover, but luck would have it, there was a nice pair of N1200's on ebay that the auction ended last night at 6:00pm I was able to pick them up for $285.00

I don't know what a pair is going for, but these were almost mint and I didn't think I got hurt.

I've had these speakers for over 30 years, and other than having my D130's re-coned about 12 years ago (luck would have it there is a authorized JBL service center here in Kansas City). They have been rocked pretty hard and never a second of trouble.

Thanks everyone for your help and advice.


Rocky

Beowulf57
01-04-2010, 09:37 AM
I have the schematic so I assume that the numbering will be the same on the new 2P-3T switch? A direct swap? So everything that lands on it's prospective terminal will land on the same on the new switch?

Rocky

If the new switch has the exact same terminal configuration...yes, a direct swap. Otherwise confirm the three switch positions make connections as per the schematic before soldering. A multimeter in DC resistance mode will help you to figure it out for sure.