"fingers" on edge connectors

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brianroth
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"fingers" on edge connectors

Post by brianroth » Sun Feb 12, 2017 10:50 pm

OK...lol...giving a hint on a new project here! <g> 500 cough cough.

15 contacts at 0.156" spacing.

(/sidebar) WHERE DID 0.156" COME FROM???? 5/32" equals 0.15625". I would think that over many fingers the spacing would drift...(/sidebar).

ANYWAY...

What would be suggested for plating on a circuit board? yes...I've read this and that re. "hard" nickel and gold.

What should I specify for Olde School circuit edge connectors that will last for many insertions? What vendor can do that without a huge quantity order?

Thanks!

Bri
Professional audio and video systems design/installation/maintenance.
www.BrianRoth.com

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JR.
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Re: "fingers" on edge connectors

Post by JR. » Mon Feb 13, 2017 11:28 am

I would avoid these unless there was some compelling reason.

There are more robust modern connector systems.

Of course the customer is always right.

Gold plated fingers (over nickel) on PCB are not cheap.

JR
Don't only half-ass tune your drums. Visit https://circularscience.com to hear what properly "cleared" drums sound like.

brianroth
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Re: "fingers" on edge connectors

Post by brianroth » Mon Feb 13, 2017 11:52 am

The standard connector for 500 series modules and the "lunchboxes" is that infernal edge connector which API began using decades ago.

Bri
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JR.
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Re: "fingers" on edge connectors

Post by JR. » Tue Feb 14, 2017 9:54 am

I used them in very early consoles (decades ago),,, absolutely horrible... poor mechanical indexing for self alignment, etc. Probably less of an issue for small modules.

Contacts exposed to environment so easily corrupted, gold is necessary, but I've seen fingers come off PCB due to poor adhesion (and perhaps heating).

Good luck.

JR
Don't only half-ass tune your drums. Visit https://circularscience.com to hear what properly "cleared" drums sound like.

brianroth
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Re: "fingers" on edge connectors

Post by brianroth » Tue Feb 14, 2017 7:55 pm

I regularly encounter edge connectors on the older desks that I service/restore. SSL, MCI, Trident, and API just to name a few. I would NOT use that style connector on a new design except for the fact that the 15 pin format is standard for the highly popular 500-series "lunchbox" gizmos...and there are dozens (hundreds?) of preamps, EQ's, compressors, etc. manufactured by dozens of companies in that form-factor. For instance:

https://www.sweetwater.com/insync/500-s ... ing-guide/

I discovered that Sullins offers a "male blade" connector which looks like an attractive alternative. Example which has a fairly decent photo:

https://www.digikey.com/product-detail/ ... ND/1922847

Alas, the correct form factor I would require seems to be a special order item, so I'm back to finding a PC board fabricator which can apply the appropriate plating(s) on the fingers.

BTW....what connectors did you use for the AMR modules?

Bri
Professional audio and video systems design/installation/maintenance.
www.BrianRoth.com

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JR.
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Re: "fingers" on edge connectors

Post by JR. » Wed Feb 15, 2017 9:02 am

brianroth wrote: BTW....what connectors did you use for the AMR modules?

Bri
Ribbon cable and multi-pin (molex?) headers/connectors.

Back at Loft (70s) we/they used edge connectors, mechanical alignment in big modules was another PIA.

JR
Don't only half-ass tune your drums. Visit https://circularscience.com to hear what properly "cleared" drums sound like.

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mediatechnology
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Re: "fingers" on edge connectors

Post by mediatechnology » Sun Feb 19, 2017 8:56 am

Part will become a non-stocking item when stock is depleted
Looks like that Sullins part is discontinued at Digi-Key.

MicMix used a male right angle similar to the Sullins in some of their very early Studio C Reverbs.
John Saul, one of the co-owners, had been an aerospace engineer and refused to use PC edge fingers.

With the 500-series format you're just stuck using them and finding a PC board house that will do it in gold may be difficult.
https://ka-electronics.com

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emrr
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Re: "fingers" on edge connectors

Post by emrr » Sun Feb 19, 2017 11:23 am

That Sullins part looks like a miniaturized Amphenol blue ribbon connector, which also seems unloved.
Best,

Doug Williams
Electromagnetic Radiation Recorders

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