Alternative Rack/Power Supply for Kepex Gates?

[James Guitar]

howdy:
i have 2 kepex gates that are in need of a rack and power supply. anybody know if there is an alternative to the valley people rack/p.s.? i searched the previous posts and couldn't find anything about them. i would happily use the valley racks but i can't seem to find any around.
any help would be greatly appreciated,
thanks,
-J

[brianroth]

Sounds like you'll need to build up an enclosure for the two modules. All I can find in my files is service info for the Kepex II (Valley People). It used a double sided edge connector (center spacing unknown) with 30 contacts on each side (60 total). The power supply was bipolar +/- 15 VDC. A Power-One or similar open frame linear module would work fine.

I don't know how similar the original Kepex (Allison Research) is to that in terms of edge connector or power spply voltages.

Bri

[James Guitar]

thanks a lot for that info. very helpful!
-J

[brianroth]

So, which Kepex version do you have..the original, or the "II" version?

I *just* came across a schemo of the original (Allison), but that's it...just the schemo. My Valley Kepex II info-stash is much more extensive.

Bri

[James Guitar]

i've got the allison kepexes (the originals). what would be missing from the schemo in order to build the box? sorry if that's a stupid question...
-J

[nosebleedaudio]

I had one of those and have schematic, it is a single 24 volt supply.

[James Guitar]

nice. did you build the box? is it possible to send me a copy of the schematic? i would appreciate it greatly and would of course cover any costs. if not, i understand...
-J

[nosebleedaudio]

Originally Posted by James Guitar

nice. did you build the box? is it possible to send me a copy of the schematic? i would appreciate it greatly and would of course cover any costs. if not, i understand...
-J

Just to make sure we are talking about the same unit do you have a pic of it?
WWW.jmkaudio.com

[James Guitar]

here's one...
-J

[nosebleedaudio]

Originally Posted by James Guitar

here's one...
-J

That's it...go to web site and email me. I could build a power supply if you need one, single 24 volt is pretty common.

[James Guitar]

will do right now. thanks...
-J

[brianroth]

Originally Posted by James Guitar

i've got the allison kepexes (the originals). what would be missing from the schemo in order to build the box? sorry if that's a stupid question...
-J

Well, the basic schemo for the Allison should give you enough info since it seems to have the pinouts for the edge connector. My Valley version has a detailed diagram of the edge connector, parts layout, etc.

I just posted the Allison 500 version here:

http://www.brianroth.com/library/kepex_500.jpg

(No link on my "library" page yet).

Bri

[brianroth]

Originally Posted by nosebleedaudio

I had one of those and have schematic, it is a single 24 volt supply.

Now that I looked closer at the Allison schemo, in addition to +24V, it also requires +100 VDC for the neon lamps in the "light meter"!

Bri

[James Guitar]

thanks a lot!
-J

[brianroth]

James, you'll need to do your own reverse engineering of the edge connector (contact center spacing, which end is which, etc).

Bri

[nosebleedaudio]

Originally Posted by brianroth

Now that I looked closer at the Allison schemo, in addition to +24V, it also requires +100 VDC for the neon lamps in the "light meter"!

Bri

If yours has LED's instead of Neons the 100 volts is not required. Should be easy to see which ones they are. Both of mine were LED's.

[James Guitar]

Originally Posted by nosebleedaudio

That's it...go to web site and email me. I could build a power supply if you need one, single 24 volt is pretty common.

i went to jmkaudio.com yesterday and emailed you. did you get the message?
-J

[thedug]

Thanks for the kepex schematic.

Doe anybody have a gainbrain schematic?

What about kepex or gain brain manual?

Douglas

[thedug]

I'm repairing a kepex and R26 is bad and I have no idea what it is. It is a big metal disc and on the schamatic it is either labeled 30 or 50 I can't tell..

[dbbubba]

On my original schematic that is circa 1972 R27 only says "R27 50 THERM"

It appears to be a thermal "protection" resistor linking the +24V audio rail and the input and GR circuitry.

BTW, I have a lone an original Kepex power supply.
It functioned fine last time I used it.