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HP Forum Archive 13

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34C weights
Message #1 Posted by james (UK) on 29 Oct 2003, 8:39 a.m.

Since my last queries on the 34C Calling Captain Zener I have been thinking about how to tell whether mine is a solderless one without finding a crowbar to lever the case halves apart - is weight a reliable indicator? The 34C specs in the Museum give the weight as between 6oz and 8oz with earlier models weighing about 1.5 oz more than later. Mine tops out at 6.5oz - is it safe to infer that mine is a later model and has soldered chips or do I need to have a couple of stiff drinks and go inside the machine?

Captain Zener to the Rescue...
Message #2 Posted by CAPTAIN ZENER on 29 Oct 2003, 3:52 p.m.,
in response to message #1 by james (UK)

Sorry to have missed your urgent cries for help, but even if you were on a speeding locomotive that just shot off a cliff, on October 17th, Captain Zener was preoccupied on the planet Krypton with this georgeous Hollywood gal wearing a tinfoil brazierre.

NOW THEN......

Dear Captain Zener

1) The dreaded 2 disease - fortunately it seems to be OK with full blanking when calculating functions (eg the Gamma function) - is there any preventative maintenance that can/should be undertaken to try and keep it sound?

YES DONT TAKE IT APART!!!!!!! Here is the best plan to avoid "2 disease", based on our limited knowledge thus far ....... if it works properly, do not disassemble to the level where the chips fall out. YOu can, however, take it apart enough to lubricate the slide switches :o)

If it's a soldered unit, you really stand a good chance that it will keep on tickin' for the long haul.

If its a solderless unit, use it and enjoy it until the very first bit of obvious unreliability (display flickers, you get an "Error 9" etc etc). Then its like you have a kidney stone and you have to go to the hospital. And who knows if it will be fixed right or not.... you have to take a chance then. At that point you DO take it apart and you DO have the chips fall out onto your desktop. You have to clean all the contacts underneath all the chips, use a bit of lube-oil to help keep things bright & shiny, and then reassemble.

(that's the Luiz Viera plan, haven't heard from him in awhile).

THE PROBLEM is if you take it apart to the chip level, and try to clean each leg of each chip, your ESD (your polyester socks, the flourescent lamp whining overhead, etc) are going to induce "2 disease" into the prehistoric non-ESD protected chips (probably NMOS, etc, or heck maybe they are bipolar, except bipolar was fairly rugged, so must be NMOS w/o static protection).

At that point you would be on a metal desktop, with aluminum foil stuffed into your socks and alligator clips grounding you to the desktop surface. At that point MAYBE you would not destroy the chips (50-50 chance) I have yet to try these methods but have great fear, just because one can, in theory enter the cave and slay the dragon, does not mean you will succeed when YOU try it.

"2 disease" is a miserable outcome, like you are still alive but you are stuck in a wheelchair, its just not the same as being 100% functional.

**** So in summary, and I hope I did answer clearly, take it apart and lube the slide switche (I preferred a Q-tip well-moistened with "TRI FLOW" which is a WD-40 with Teflon particles added) and don't take it down to the chip level. Even for taking apart just to the circuit board level, it would be prudent to ground your own body to one of the battery terminals of the calculator, or to the main circuit board frame, even while lubricating the slide switches. (aluminum foil stuffed into your smelly moist socks would be a very expedient ground path).

2) I haven't psyched myself up yet to try and open it - without opening it is there anyway to tell whether it has the solderless construction - serial no. 2033S?

Weight really and truly is a good indicator. If its "heavy" its probably solderless. If its "light" its soldered. Just use your best imagination and judgement.

3) Should I open it anyway in order to lubricate the on-off and run-prog switches?

Yes. If you plan to use it more than once a month.

4) What's the best stuff to clean the display (a few minor scratches) and the keyboard (suffering from bits of sticky black plastic from the pouch - I have just put the pouch through the washing machine [yes - I remembered to take the 34C out first] following a post I saw a while ago on the forum which did the trick on a 41CV pouch which suffered from the same problem)?

I've never had to cover up any scratches, most people wind up recommending Armor All, or other equivalent automotive products (dashboard polish, etc).

WELL THAT'S IT FROM CAPTAIN ZENER.... and about that gal on Planet Krypton, her name is Kryptonia and that tinfoil brazierre is just too hard to forget.... so I'm up and awayyyyyyyyyy.......... until next time!

- CZ

aluminum capacitors
Message #3 Posted by CAPTAIN ZENER on 29 Oct 2003, 3:58 p.m.,
in response to message #2 by CAPTAIN ZENER

If you do take the electronics module apart on a SPICE calculator, there are two aluminum electrolytic capacitors on the power supply board. It would be prudent to replace them with dipped-tantalum so that they never need to be serviced again.

Their values are unpopular (22uF, 10V dipped tantalum replacements) therefore have to locate them in advance of taking the unit apart.

These are all reasons why SPICE calculators are just tough enough to service that there ought to be a little service shop somewhere to deal with it (my garage?).

Rubber keypad membranes are not always present. Its a part that we ought to be able to have tooled up and more of them stamped. I tried to specify the material and simply could not thus far. There is a "dry lubricant" on the rubber sheet. I will however try again in the future.

BTW if any of us gets the least-bit serious about the SPICE calculator series, it ought to be fairly easy to have new manuals printed up, new boxes printed up, and a textile sewing shop make us a few thousand new HP furry cases.

C'mon guys.... think big! We can slay the Carly beast !

Thanks for the info Captain.....
Message #4 Posted by james (UK) on 30 Oct 2003, 5:50 p.m.,
in response to message #2 by CAPTAIN ZENER

At least it looks as if mine is soldered from the weight so one less thing to lie awake at night worrying about. My 34C is in daily use at the moment as I'm still exploring it (code for being so over the moon with it that I can't keep my hands off it - another advantage of red leds - you can still play with it at night!!) so I guess I will need to have a go at lubing the switches.

Enjoy Kryptonia, the tinfoil bra should sort any static! And keep a wary eye out for any lumps of Carlyite lying around.

Thanks again.

Carlyite kills everything, HP-34C rules
Message #5 Posted by CAPTAIN ZENER on 31 Oct 2003, 4:50 a.m.,
in response to message #4 by james (UK)

Glad to hear you are enamored with your HP-34C . Isn't it a sweetheart? Captain Zener says confidence it could be manufactured profitably even now, because it's just that cool. There is however an MBA Mafia Marketeer's society that says 'nay nay nay' and some are even on this chat board. They are kind of like sheep. Sheep say 'baah baaah baah'.

Yes, Carlyite kills everything. It's a real bitch if you get any on you.

Back to that tinfoil brazierre...... yeah, the tinfoil must offer ESD protection.

But I can "run the system" with the ESD protection removed.

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