Re: [CAD_CAM_EDM_DRO] LONG floppy drive cable source

On Saturday 11 May 2002 12:33 am, you wrote:

> On Friday 10 May 2002 11:57 pm, you wrote:
> > Any sources for shielded floppy drive cables (power
> > and data) in the 20FT range? Need to go from the
> > enclosure to the operator pendant. I suspect this is a
> > DIY length
> > cable. Anybody make shielded connectors for them? Or
> > isn't sheilding critical?
> >
> > thanks
> >
> > dk
>
> I'm not sure the floppy interface will run with a 20' cable. Power would be
> OK if you used big wire and maybe put a decoupling cap at the floppy end.
> The data rate over rhe data interface is probably is too fast to be happy
> about 20' of ribbon cable. Maybe 20' pieces of coax terminated in the
> characteristic impedance of each data and control circuit. That'd be a heck
> of a cable! I'll see about looking up the max cable length for floppies.
>
> Matt

Well, here's a usenet thread on it:

http://groups.google.com/groups?hl=en&frame=right&th=c1abb89f47115d37&seekm=45AB1F7DB1E266D3.BFDE8F608500D19F.98D8CEAE5F0F41C9%40library-proxy.airnews.net#link1

Basically, the length limit is officially 18". Several guys reported having
working drives with 5' and even 8' cables. One old timer said he had run old
floppies on S-100 systems on 25' of cable.

Alpha makes shielded ribbon cable, but it's very stiff and should be used
with idc connectors specially made for that cable. I don't know if shielding
would really help unless there was a lot of EMI/RFI.

Let us know how it goes.

Matt