HP 2114A value??

From: Jay West <jwest_at_classiccmp.org>
Date: Wed Jan 14 13:03:05 2004

You wrote...
> Ouch! Can you tell me what it looks like or better yet send me a
> or a URL to a picture. I have some old media around. I may have something
> that will work.
I believe the manual states something to the effect of "mechanically
equivalent to an IBM 2313", but NOT interchangeable. There is a major thing
to watch out for here. The disk cartridges are virtually identical between
the 7900, and the 7905/06. However, one is a 50 mil platter and one is a 75
mil platter. I forget which one goes with which drive. I believe the 75 mil
is 7900 and 50 mil is 7905/06 but I will verify this for sure. Most media
has an HP part number on it that will tell you for sure, but once you get
used to looking at them you can tell easily by opening the cartridge access
door and looking at the platter (thick or thin). Put one media in the wrong
drive and it won't work, put the other media in the wrong drive and you're
gauranteed a very expensive and time consuming set of repairs :) To my
knowledge, the cartridges used in the 7900/05/06 are not the same as in
other common 14" drives I've run into at least. You may also run into
problems using other media due to the certification of the density of the
platter. I THINK the ones HP used were 2200?

> I KNOW what you mean! I used to repair hard dirves for Burroughs Corp
> I've replaced many a head and disk cartridge due to bad batteries.
> Burroughs used Saft batteries and they're JUNK!
They are a AA form factor nicad battery. Read the specs off the battery and
get replacements just like it. I got mine at "batteries plus", it's a chain
of battery stores here.

> Nope it's a 7900A. I didn't realize that it had a fixed disk :-) Is
> there any reason I can't use it like it is (without a removeable disk)for
> the time being?
YES there is a reason. The two heads for the removable platter and the two
heads for the fixed platter are on the same armature. You can NOT run the
drive at all without the removable media in place.

> Are the NiCads used for the fixed disk?
They are used to retract the voice coil, which holds both sets of heads.
They are not independent, so the nicads are for both.

> Is the air filter
> system used for the fixed disk or just the removeable one?
Air blows from the vents in front (replace the foam in the access door by
the way), through the squirrel cage to the filter. The filter splits the
airflow in two. One (through the big orange tube) blows over the power
transistors on the regulator board at the bottom. The other air flow goes
into the bottom (fixed) platter chamber. A hole in the top of the bottom
chamber lets the air blow into the media cartridge casing (when you put the
media in place and close the door, a trap door in the bottom of the media
opens right over the hole in the top of the fixed chamber). All air is
exhausted out the opening where the heads go in and out.

> No this one appears to only have the front section of cards and they're
> accessed through the top cover and not the front. It doesn't appear to
> a back section. The back appears to be occupied by a largish core memory
> block on the left side and a couple of power supplies. The core memory is
> in a stack and appears to be about 5" cube.
Then it does have a front and back section, back section for memory. In the
front, there should be some designation as to what slots are for cpu cards
and what slots are for I/O cards. The 2100 for example has blue on the cpu
card section and red on the I/O card section (as the slots are different
electrically), and a black section for the memory. Sounds like the core
memory section on the 2114 is VERY different from the core section on the
2100 (and 2116).

> I'll go back tomorrow and pull the cards and take a closer look.
Ok, with the card numbers off the circuit boards I could probably tell you
more. I'd recommend going to great lengths to find the docs that supposedly
came with the system!!


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Received on Wed Jan 14 2004 - 13:03:05 GMT

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