[Coco] CocoSDC

[Gene Heskett]

On Monday 13 October 2014 01:40:04 nickma2 at optusnet.com.au did opine
And Gene did reply:
>  > Certainly it is good for the Coco software use and preservation.
>  > Somehow I prefer to use the old, original hardware.
>  > It's a different feeling from using emulators, FPGAs, SCDs, etc.
>  > I'm not saying goodbye to my "obsolate floppy drives" just yet. :)
>  > 
>  > Kandur
> 
> Don't worry. They'll be saying goodbye to you first.
> 
> The drives and media won't last. The media will start deteriorating to
> the point of the magnetic material rubbing onto your drive heads. When
> you start hearing whistling noises from the disks as they spin, it's
> time to do a backup!
> 
> I still keep my old drives too, just haven't had to turn them on for
> over a year.
> 
> Nick

Knock on  wood, I am not yet suffering from the bad media horror stories I 
am reading here.  All my coco stuff, with at least a thousand floppies, is 
in in the basement, setup on its own "computer" desk.  One of the things I 
learned about magnetic media in general is that it is very sensitive to 
both heat and humidity.  High humidity specifically turns the media into a 
very abrasive substance that can eat up a 1000 hour rated vcr head drum in 
150 hours, higher heat multiplies the effect.  We kept our commercial 
tapes in a small vault at KRCR that was held at about 45 degrees and as 
dry as an overworked air conditioner could make it, probably under 20% RH 
on average.  My full basement is ac'd in the summertime, well enough from 
leakage in the ductwork to stay at about 65F and by the same duct leakage 
heated in the wintertime, is about 73F right now and has two dehumidifiers 
running 24/7, set for about 55%, and they pull about 6 gallons of water 
out of the basement air daily.

So my media and drives are holding up so far.  I think the dryer and 
usually cooler environment has something to do with their apparent 
longevity.

At one point when I was the tx supervisor at KXNE-TV19 in Nebraska for the 
Nebraska ETV Commission, they had 3 Ampex 2" quad tape machines in a clean 
room, air conditioned, dry, with precipitron air filters. A 1 hour roll of 
tape went in that room and only left when it was worn out, so the tape 
lived in that clean & cool environment 24/7.

In those days there were several headwheel refurbishers in business.  They 
had a rotary transformer failure so they dug out a spare wheel and 
installed it.

While processing the paperwork to get it fixed, they found 2 things.
1. It was a 'soft' head, pro-rated warranty of only 250 hours.
2. It had just north of 7000 hours of run time on it!
The vendor of that rebuild measured it, saw no reason to do a full 
rebuild, so they fixed the broken wire on the transformer and sent it 
back, gratis.

It was re-installed in that machine and finally wore out a few hours short 
of 11,000 hours runtime.  Not bad for a cheap 250 hour head.  And all 
because of the environment it and the roll of tape on it was kept in.  
What those 3 machines were was the 1 hour delay needed because half of 
Nebraska in on CST and half of it is on MST time.

Cheers, Gene Heskett
-- 
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US V Castleman, SCOTUS, Mar 2014 is grounds for Impeaching SCOTUS