11 Sep
2005
11 Sep
'05
8:50 p.m.
Joe,
I tried to send you an Email ( offline ) from the address on your webpage.
No go. I was trying to spare the rest of the list our ramblings in-so-far as
to the possible purchase of an MMU or two. Please feel free to contact me
offline concerning same.
Best regards, Steven
Joe,
I'm taking a stab at this being your correct Email address ( from your
homepage ). You do indeed have the Mass Memory Unit as described below ( in
a post that hasn't " posted " yet ). Where abouts in the country are you
located ( I'm in Southern California very near Anaheim ). The reason I'm
asking is if possible I would drive some ( reasonable ) distance to obtain
an MMU or two. I would think shipping might be costly ( or not ... ) ? Have
you thought about a price for these guys ( my first-born is spoken for
unfortunately ) ? Believe it or not, new these sold for about $250 K as I
recall. I'm not trying to cheat the system here, just getting impatient with
the slow postings... Please advise ...
Best regards, Steven Canning
----- Original Message -----
From: "Steven Canning" <cannings at earthlink.net>
To: "General Discussion: On-Topic Posts Only" <cctech at classiccmp.org>
Sent: Monday, September 05, 2005 1:35 PM
Subject: Re: Mass Memory Unit from Space Shuttle
John is correct about the 5 Volt logic control
signals. The prime power is
+28 VDC spacecraft power. They have in-rush current limiters on the prime
power input and will run down to + 24 VDC and up to +32 VDC ( there is a
pre-regulator up front ). These are linear scan units ( not helical scan
like a VCR ). Sounds like you have the MMU ( Mass Memory Unit, the smaller
one ) and not the STR ( Standard Tape Recorder, the big guy ). These units
( MMU ) were digital only, and were used to download programs to the five
general purpose IBM computers ( configured like IBM 360s ). Part of this
function was to drive the " glass " dashboard ( CRTs) that provided info
on
engines, etc. There was not enough room for all the
standard instruments
on
the " dash " that would have been required.
So you could pull-up " virtual
instruments " like they have on the Toyota Prius dashboard. The two tape
reels were not driven, but maintained tape tension through differential
gears connected to a " gyrator " spring that provided relatively constant
torque between the two counter rotating reels. The tape was " pulled "
through a proprietary delta drive capstan system which incorporated the
read
/ write heads. Remember this thing has to survive the
G-force of liftoff
and
run in a micro-gravity environment.
Best regards, Steven Canning
----- Original Message -----
From: "John C. Ellingboe" <john at guntersville.net>
To: "General Discussion: On-Topic and Off-Topic Posts"
<cctalk at classiccmp.org>
Sent: Saturday, September 03, 2005 7:39 PM
Subject: Re: Mass Memory Unit from Space Shuttle
a
"Joe R." wrote:
>
> I found a pile of these things this morning. They are made by
Odetics
> in Anaheim Ca. After I got home with them I
realized that they are for
the
> > space shuttle. Does anyone know anything about them? I THINK they use > > tape drive inside. I haven't opened one
up yet but I saw the remains
of
a
> tape drive at the same place and I think it
was the guts out of one of
these.
Joe
I'm not sure about how many the shuttle used but there is one on
each solid rocket booster. The had two tape reels stacked on
top of each other. The control signals are 5V logic and power
is probably 24V DC. I try to locate a contact to get some data
in them.