more rack ideas

[Bob Zimmer]

At 01:25 PM 4/29/97 -0400, you wrote:
> -- Excerpt from David Halliday (Volt Computer)
>> There's a number of "standards" used in industrial control systems -
>> don't know that there was any standard for wiring but the card size (
>> and the 22/44 card edge connector ) was pretty stable.  The card cages
>> were cheap and a good size to work with.
>
>And so I challenge; can 22 pins be sufficient for all
>connections for all modules of a voice to the panel?
>Obviously, this depends on the features of the modules,
>but generally speaking, what do you people think?
>
>> Hal Chaimberlain's book on Musical Applications of Microprocessors has
>> the idea of putting a header on each card and using ribbon cable to
>> daisy-chain them.  This is nice since you don't have to worry about
>> making a backplane and you can loop from card to card even if the
>> cards are not in a common rack.  He sugested Molex connectors ( Molex
>> is a prominent manufacturer ) but ribbon cable may be better ( newer,
>> cheaper, denser )  He drove the audio into current sinking inputs so
>
>Hey, using mass produced PC technology saves money
>and results in better availability.  This might better
>lend itself to standardization.  Obviously, if I use the
>aforementioned card cage, I'll be more or less on my own.
>But, I already *have* the card cage so, standard or not,
>I'm obligated by frugality to build at least one...
>
>steve

Be warned as I was, ribbon cable is only capable of carrying about 100ma per
wire.  If I remember right, its like 26 or 28 gauge wire.  If you are doing
a number of modules, IDC connectors and ribbon cable is a very easy and
clean solution, but it just is not capable of carrying enough current.

If someone is only going to do a few modules per run of ribbon, it might
work out!

If so, please let me know, I've got about 20 gold IDC ribbon connectors, 25'
of cable and an IDC crimper that are looking for a good home (reasonable
price!).



  >=== Bob Zimmer -- Philadelphia PA ===<
  >=== bzimmer at voicenet.com          ===<