The No.1 Website for Pro Audio
Alternative Rack/Power Supply for Kepex Gates?
Old 6th July 2005
  #1
Lives for gear
 
James Guitar's Avatar
 

Alternative Rack/Power Supply for Kepex Gates?

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
Old 7th July 2005
  #2
Lives for gear
 
brianroth's Avatar
 

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
Old 7th July 2005
  #3
Lives for gear
 
James Guitar's Avatar
 

thanks

thanks a lot for that info. very helpful!
-J
Old 7th July 2005
  #4
Lives for gear
 
brianroth's Avatar
 

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
Old 7th July 2005
  #5
Lives for gear
 
James Guitar's Avatar
 

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
Old 7th July 2005
  #6
Lives for gear
 
nosebleedaudio's Avatar
 

I had one of those and have schematic, it is a single 24 volt supply.
Old 7th July 2005
  #7
Lives for gear
 
James Guitar's Avatar
 

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
Old 7th July 2005
  #8
Lives for gear
 
nosebleedaudio's Avatar
 

Quote:
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
Old 7th July 2005
  #9
Lives for gear
 
James Guitar's Avatar
 

here's one...
-J
Attached Thumbnails
Alternative Rack/Power Supply for Kepex Gates?-kepexes.jpg  
Old 7th July 2005
  #10
Lives for gear
 
nosebleedaudio's Avatar
 

Quote:
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.
Old 7th July 2005
  #11
Lives for gear
 
James Guitar's Avatar
 

will do right now. thanks...
-J
Old 8th July 2005
  #12
Lives for gear
 
brianroth's Avatar
 

Quote:
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
Old 8th July 2005
  #13
Lives for gear
 
brianroth's Avatar
 

Quote:
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
Old 8th July 2005
  #14
Lives for gear
 
James Guitar's Avatar
 

thanks a lot!
-J
Old 8th July 2005
  #15
Lives for gear
 
brianroth's Avatar
 

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

Bri
Old 8th July 2005
  #16
Lives for gear
 
nosebleedaudio's Avatar
 

Quote:
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.
Old 8th July 2005
  #17
Lives for gear
 
James Guitar's Avatar
 

Quote:
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
Old 23rd September 2008
  #18
Gear Nut
 

kepex/gain brain schematic/manual

Thanks for the kepex schematic.

Doe anybody have a gainbrain schematic?

What about kepex or gain brain manual?

Douglas
Old 27th September 2008
  #19
Gear Nut
 

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..
Old 28th September 2008
  #20
Lives for gear
 

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.
Old 2nd March 2014
  #21
Gear Maniac
 

Maybe someone has some input regarding my RM-160 as well? With new caps, it's putting out 43.2V unloaded; with 8 modules racked it was still supplying mid-30s. The current limiting resistor feeding the LED was toasted, perhaps from receiving 43V?

Nothing is visibly fried, the resistors measure on spec. The trimmer pot (R4) measures fine, but it doesn't have any effect on the output voltage. Is there something obvious I'm missing?

Many thanks,
Seth
Attached Thumbnails
Alternative Rack/Power Supply for Kepex Gates?-rm-160.jpg  
Old 5th April 2014
  #22
Lives for gear
 
nosebleedaudio's Avatar
 

You could simply install a 7824 and forget it...
it Should be 24V....Not 43V...Loaded or not...
Old 5th April 2014
  #23
Gear Maniac
 

Thanks! I finally got it sorted with a couple of new transistors. Transformer is awfully noisy, but the thing seems to be working properly....
Old 28th October 2015
  #24
Here for the gear
Hi,

I'll be receiving 6 original Kepex 500 units soon, they come with the CM-001 Console Mount enclosure.

Does anybody has a Allison Research LX-100 Power Supply i can buy and use to properly fire them up ?

Another option would be to buy a RM-160 and Rack Mount em.

I'm also considering doing an alternative PSU for them, but i'm not that expert with electronics to build myself one, can anybody recommend some compatible PSU i can buy ?

@ nosebleedaudio : i think i read somewhere on GS that you also modded some of them with normal LEDs instead of neon lamps.

I think i can do that if its not that difficoult, but could you provide that document Buff did to realize the mod circuit ?

Thanks everybody for all the help you may send !

K
Post Reply

Welcome to the Gearslutz Pro Audio Community!

Registration benefits include:
  • The ability to reply to and create new discussions
  • Access to members-only giveaways & competitions
  • Interact with VIP industry experts in our guest Q&As
  • Access to members-only sub forum discussions
  • Access to members-only Chat Room
  • Get INSTANT ACCESS to the world's best private pro audio Classifieds for only USD $20/year
  • Promote your eBay auctions and Reverb.com listings for free
  • Remove this message!
You need an account to post a reply. Create a username and password below and an account will be created and your post entered.


 
 
Slide to join now Processing…
Thread Tools
Search this Thread
Search this Thread:

Advanced Search
Forum Jump
Forum Jump