Hello All,
>
>While I was checking the spelling, I notice that wikipedia mentions
>another name for pop rivets is blind rivets.
>
I _love_ Wikipedia, but it certainly has its share of errors. Please: Never equate
pop rivets with "blind" rivets. Blind rivet is a sort of generic term -- meaning that
it's a form of rivet that can be used even though you do not have access to the other
side of the rivet. Blind rivets are used on commercial aircraft, but only in relatively small
quantities -- and -- each catagory of (blind) rivet is carefully chosen to perform a certain
task. Most times, when we install blind fasteners (rivets fall into the broad catagory
of fasteners), we have to get Engineering approval. Most installations of blind rivets are
actually considered temporary. They will usually be removed during a Heavy Maintenance
Visit (often several years later).
Pop rivets fall at the very bottom of the rivet catagory. Pop rivets are never used on commercial
aircraft structure, although I've used a lot of (a certain higher quality catagory of) them to fasten
things like nutplates (all they are doing is holding what amounts to a nut, in place, while a bolt is tightened).
Once tight, the bolt is tight the rivets are meaningless until you need to remove the bolt again. If the "pop" (type)
rivets don't hold, then a veritable stream of cursing insues, while you go and try to find the right drill bits
to remove the offending nutplates. Then, the little buggers almost always spin while you curse more and
try to get a small pair of ViseGrips on the bottom of them (often very difficult due to space constraints), so you
can smash them into submission, while you continue to drill them out.
"Cherry-Max" rivets are a very popular form of blind fastener (in this case, blind rivet). They have a solid
core of wickedly hard stainless steel that remains in place as the rivet is "pulled" into its compressed final
product. Not only are they relatively heavy, they do not expand in the same way that solid rivets do -- plus
you now have a dissimilar metal situation.
Speaking of pop rivets: There is a kitplane (an excellent work horse of a plane) that makes use of thousands of
closely spaced pop rivets. I used to be able to recall its name off the top of my head, but this library computer
will not allow me to open another instance of my browser (to search google and figure it out). It was a sort of ugly, boxy, utilatarian looking plane. It was so "ugly" that it was actually very cool!! It's supposedly nearly
"indestructable."
Oh, BTW, "regular" solid aluminum rivets are only very slightly smaller than their correctly drilled, and in some
cases, reamed holes. When the are compressed (bucked), they expand and tightly fill the hole. It's certainly an
impressive art to get a properly shaped "bucked" head (also called "shop head"). If the bucked head is smashed
too much or "leans" over, you've got to remove them. Technically, you are supposed to go to the next larger
size because the material around the hole is now work hardened. If everyone actually removed ever screwed
up rivet, there would be little hope of repair at a later time (because you don't have much leeway as to size).
I'm pretty sure that that's how ships remained fairly water-tight. The final result of solid rivets are not always perfect. Upon close inspection of any commerical airliner, I can find dozens of leaking or "smoking" rivets. Technically speaking, they should be replaced. Realistically, it's a case of "what are you going to do?" I did a lightning inspection on a 757 that said they were hit on short final. It was raining and miserable (and very dark). It wasn't until the last section of inspection that I realized that I'd forgotten to check a few antennas. One thing led to
another, and we eventually found way over 100 affected rivets (and outright holes). The plane was taken out of service for a couple of months, but I saw it again (with lots of very large rivets, which were used to "fill" some
of the lightning strike holes).
Always choose the correct rivet for the job(!!!).
Regards,
Robert Greenstreet
> Does anyone have any recollections or information
> about the DTC MicroFile? Data Terminals and
> Communications made it. It's a piece of furniture
> on wheels, contains a box with a dual 8" floppy drive and
> appears to be designed to sit in between a terminal
> and a daisywheel printer -- a primitive word processor?
> Haven't had a chance to crack the box open yet, and am
> curious if anyone has any concrete information.
>
> Cheers
> Brian
I just uploaded several documents on it to
http://bitsavers.org/pdf/dtc/microFile
> Date: Wed, 10 Jan 2007 18:52:14 -0800
> From: "Chuck Guzis" <cclist at sydex.com>
> Subject: RE: Compuserve wayback machine
>
> On 10 Jan 2007 at 21:29, Richard A. Cini wrote:
>
> So, exactly the same thing happened to you that happened to me.
>
> > They actually want you to pay $18/month for access, which I guess
represents
> > the legacy dial-up business.
>
> Which is exactly the opposite of what you'd expect. When I dropped
> service at the end of 2004, my monthly bill was about $9.50
/month.
> How do they expect to compete with the likes of NetZero and
PeoplePC?
>
I've actually kept my Compuserve account alive all this time as an
emergency travelling ISP.
One of the incarnations of my cable internet provider didn't allow off
net access to POP and SMTP
so I discovered that the extensive network of dialups was useful.
Under the later revs of their network, you can dial in, authenticate,
and then just use PPP to access the internet directly. You get about
3/hours/mo dial-in time for free and usage rates there after.
I logged in yesterday via the web.... it takes a little redirection to
the "native" Compuserve site as the inital screen wants a "Screen Name"
and won't accept a PPN. I thought I set a name for my account but I
don't remember it and I didnt write it down anywhere (it was too
"obvious" ;^} )
There is a Vintage Computing forum still active, and the files area
still has stuff dating way back at least to the 80s.
I am still carrying a $9.99/mo legacy subscription, but I don't think
they'll let you sign up for that anymore.
They now have a BYOA (Bring Your Own Access) rate advertised.
I noticed someone in a support forum mention some sort of backup rate
of $3/month. I'm guessing that they'll have deals to try to keep
getting some money from you if you may quit.
I just got a Cingular 8525 and an unlimited data rate, so I'll
probably drop this soon. I'm off to learn more about Windows CE.
Dave.
Date: Fri, 12 Jan 2007 13:56:17 -0800 (PST)
From: Cameron Kaiser <spectre at floodgap.com>
Subject: Re: only on govliquidation.com could this happen....
> <http://cgi.govliquidation.com/auction/view?auctionId=1090219&convertTo=USD>
>
> Lot includes....
> ...
> 10 RECTAL SPECULUMS - what?!?!
That's for inserting the typing element.
---------------------------------
ROTFL!!!
Cameron, your humour (and medical expertise) make
wading through the dreck worth while; thanks for a
good laugh!
mike
At 11:30 -0600 1/12/07, Mike wrote:
> I just checked my TI-58C, and it does indeed take a 3.3VAC 500ma power
>pack. The links I posted earlier agree. The connector is keyed. The
>part number is AC-9131. Are you sure that's the right pack, Stan? The
>references say the TI-58 uses the same AC-9131 pack.
The numbers so far are not totally inconsistent. The wart might
supply 6.x V open-circuit or low-current, but rely on the battery
pack to pull it down to 3.3V at 500 mA, running or charging. The
circuit diagram on xgistor seems to indicate there's just a 4.7 Ohm
resistor keeping the bus from being completely battery-limited.
That said, the battery pack definitely contains 3 Ni-Cad cells, each
typically around 1.1 or so V. (I have had mine apart, rebuilt with
stock Ni-Cads, ond not fried anything.) Therefore 3.3 V to the
electronics makes good sense.
One thing I would *not* do would be to plug in the calculator without
a good battery pack in place, based on the circuit diagram and on
Tony's advice pertaining to the dire consequences of similar actions
with HP calculators.
FWIW, there is one more factor in the story. TI made a printer base
(PC-100?) that you could place the calculator (TI-58, -58C, or -59)
on to generate printouts. The method of connection was to take out
the battery pack, and place the cavity that it just vacated over a
protrusion on the face of the printer, which would then expand to
lock the calculator into place. (There was also a compartment to put
the battery pack into so it could charge while you printed.) Whatever
the power supply in that doohickey was, it circumvented the battery
completely. If anyone has one of those and could measure the voltage
on its power pins, that would likely shed lots of light on what the
calculator expects. (Sadly, mine went at a garage sale while I was
away from home.)
--
Mark Tapley, Dwarf Engineer
(I haven't cleared my neighborhood)
210-379-4635 Dwarf Phone, 210-522-6025 Office Phone
>From time to time, I've wondered about riviting whenever I come across a
piece of computer cabinet metal that has rivits that have come loose or
fallen out. The current case in point is the tilt latch on an 11/44 when
it's in the 11X44-CA configuration (it's in the top of the rack, and tilts
up on gas pistons). There is a little latch on the side (best way I can
describe it is a metal rectangle cut on a diagonal) which is spring metal.
You pull this latch in from the front with a pen or screwdriver, and it then
clears the tab on the outer rack so it can tilt up. At the very back of this
spring metal latch is a rivet holding it in place. This rivit has come
loose. You can really only get to one side of it, that's when the cpu
chassis is tilted up. I believe that in other (more common) rackmount
configurations of the /44 when it's on slides that telescope out the front,
this same latch is present but it's used to allow the cpu to slide forward
rather than tilt up.
I've seen riviters working on F18's at Boeing, and it sure appears to be a
higher art form. Not sure it's something I could do, but thought I'd ask
here. I've seen all kinds of rivits - different sizes - on an H960 I believe
there are a couple? Anyways, what tools are required, where can one get
rivits, what different types are there, and is it something a neophyte like
me who has never done a rivit before can do? I'm looking for the basic intro
to replacing a rivit for someone who has never done it.
Jay West
Another of the interfaces I purchased is called an HP11284 data
communications interface, it's part of the 11285 datacomms option (which
also included firmware ROM modules for the HP9830).
Anyway, this thing is complicated. It's 2 modules that plug into the 9830
I/O slots, each contains a PCB. One is stuffed with TTL and RS232 buffers
(1488s and 1489s), the other has more TTL and 4 custom ICs. 2 20 pin ones
(no idea) and 2 40 pin ones (maybe transmitter and receiver logic).
The modules are linked by a cable, there's another cable from the first
PCB I mentioned to the podem (or whatever). It ends in a 36 pin
microribbon connector, I believe there was another cable which I don't
have that connected to that and which ended in a pair of DB25 plugs, one
for the RS232 signals to the modem, ther other carrying RS336 signals to
an aautodialler.
My first question is simple. Does anyone have this interface with that
last cable and could 'buzz out' the connections so that I can make said
cable, and/or figure out a little of the internal hardware?
-tony
Well, the subject: line says it all really, but I'd better explain if
only to avoid the 'You should be able to figure it out for yourself' (I
could, if I have the drive) and the 'Most of it's the same as the drive
in an HP9830' (it is, but it's the different bits I am interested in)
type of replies.
I've bought a few interfaces for the HP98x0 series of 'calculators' [1].
One of them is the interface for said tape drive, it's a single PCB
containing about 10 TTL chips. What I am looking for, though, is a pinout
of the interface connector on the drve iteslf so I have some idea what to
expect on the end of this interface's cable.
[1] They're called 'calculators' to get past the purchasing depatrments
of the time. They're really computers -- the 9830 in particular
programmed in BASIC, has an alphanumeric display and supports HPIB and I
believe a hard disk. Other machines in the family (9810 and 9820) are
more like calculators, but haev the same bit-serial 16 bit proceessor, etc.
-tony
We are looking for documentation on HP 500 Series BASIC software. Our
immediate need is to learn the syntax of the MSI (Mass Storage Is)
statement. Unfortunately, the form of the statement is not the same as with
HP RMB or 9845 BASIC (we've tried those).
Jon Johnston
HP Computer Museum
http://www.hpmuseum.net