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<p>How did you format the tape? A TU55 DECtape could be formatted,
but I thought that the cassette tapes had to be bought
preformated.<br>
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<div class="moz-cite-prefix">On 3/31/20 5:14 PM, Clem Cole wrote:<br>
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style="font-family:arial,helvetica,sans-serif">exactly. You
could use some COTS tapes if you carefully cut the case with a
box cutter to make the notch, which we as students got pretty
good at. IIRC Memorex worked best. You could not use the
really cheap tape, but DEC used saturation recording. The
official DECcassettes and compatible from the aftermarket
sellers cost more than what you got at the music store in
Oakland. </div>
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<br>
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<div dir="ltr" class="gmail_attr">On Tue, Mar 31, 2020 at 5:04
PM Dave McGuire <<a href="mailto:mcguire@neurotica.com"
moz-do-not-send="true">mcguire@neurotica.com</a>> wrote:<br>
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<blockquote class="gmail_quote" style="margin:0px 0px 0px
0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><br>
He's talking about DECcassette, not DECtape. The
DECcassette looks<br>
like a standard Philips-style audio tape (of Walkman fame) but
has a<br>
notch in the top.<br>
<br>
-Dave<br>
<br>
On 3/31/20 5:01 PM, Thomas DeBellis wrote:<br>
> Are you referring to DECtape II? That was a cassette.<br>
> <br>
> I was referring to the (nearly indestructible) earlier
format: simply<br>
> called DECtape or DECtape I. It's the same media as
LINCtape (a small<br>
> reel), but with a very different controller. These could
store a little<br>
> over 70K (36 bit) words.<br>
> <br>
> On 3/31/20 4:40 PM, Clem Cole wrote:<br>
>> Dave the TA11 (DEC proprietary Phillps Cassettes)
were 150 ft long. <br>
>> I just looked in my 1976 Peripherals Handbook --
Tape capacity of<br>
>> 92,000 bytes (not kbytes mind you). Two tapes per
TA11; one for the<br>
>> OS and the other the user. We had a couple at CMU
on 11/20's running<br>
>> RT-11 in the EE Digital lab for the RT system's
course - in fact, the<br>
>> famous "110v non-maskable interrupt" occurred on one
of those machines<br>
>><br>
>> On Tue, Mar 31, 2020 at 3:14 PM Dave McGuire <<a
href="mailto:mcguire@neurotica.com" target="_blank"
moz-do-not-send="true">mcguire@neurotica.com</a><br>
>> <mailto:<a href="mailto:mcguire@neurotica.com"
target="_blank" moz-do-not-send="true">mcguire@neurotica.com</a>>>
wrote:<br>
>><br>
>> On 3/31/20 2:33 PM, Thomas DeBellis wrote:<br>
>> > 32MB really was ginormous back in the day;
our labs had RT on<br>
>> RK05's,<br>
>> > which held about 2.5MB. Way more than a
DECtape.<br>
>><br>
>> When I started out, I had it on RL01s. But I
suspect you have a few<br>
>> years on me. ;) That was quite a bit of space at
the time.<br>
>><br>
>> -Dave<br>
>><br>
>> -- <br>
>> Dave McGuire, AK4HZ<br>
>> New Kensington, PA<br>
>><br>
<br>
<br>
-- <br>
Dave McGuire, AK4HZ<br>
New Kensington, PA<br>
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