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Hi from a newbie member

PostPosted: Sun Jan 08, 2012 12:39 pm
by sully
Hello folks i am in the UK i have been a user of of Sinclair and jupiter Aces since they came out in the early 80s i had a Jupiter Ace and a ZX80 as soon as they came out and I Have been hooked on them ever since.
Ive been a collector of Jupiter aces and ZX80s I own a number or other vintage computers but i feel the jupiter Ace is the most important vintage computer as its the only computer ever to ship with the Forth language as standard.
These are some pictures of my collection
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Re: Hi from a newbie member

PostPosted: Sun Jan 08, 2012 1:00 pm
by lizardb0y
Dude! Wow! That's a fantastic collection of some truly classic machines :)

I'm a Sinclair enthusiast myself, and have also wanted a Jupiter Ace every since they were first advertised in magazines. The difference is I never had one, and now there's no way I can afford one.

Welcome to the forums :)

Re: Hi from a newbie member

PostPosted: Sun Jan 08, 2012 1:44 pm
by tezza
Far out! A field of Forth footsoldiers!

The Jupiter Ace is also on my "yet-to-acquire-but-unlikely-to-afford" list.

Welcome to the forums!

Re: Hi from a newbie member

PostPosted: Sun Jan 08, 2012 3:15 pm
by Gibsaw
Holy god... These are in the category of "never likely to get even ONE" and you have six? :shock:

I take it these were acquired closer to their original time of relevance?

Re: Hi from a newbie member

PostPosted: Sun Jan 08, 2012 3:41 pm
by sully
Cheers yes i got these about 9 years ago
With The Jupiter Ace 4000 There was there was only 800 ever made
On Ebay there is only Two or Three a year for sale.
I would never switch these on as electricity would Damage the circuitry because of their age.
I seal them all in oxygen Proof anti-static bags and hope they last the years.

Re: Hi from a newbie member

PostPosted: Mon Jan 09, 2012 10:24 am
by tezza
sully wrote:I would never switch these on as electricity would Damage the circuitry because of their age.

Really? But surely if you won't switch them on for fear of damage they might as well be non-working, yes? The end result is the same as you can't demostrate them working or play with them?

Each to his own I guess. For me, I like to know the status of the electronics. I'm sure you'll find most will work. Most Zx81's do and they are the same vintage. The keyboard as the weakness with the ZX81's though. The keys do tend to stop functioning after a while as the connector gets brittle and snaps. Most of the time they boot up though.

Re: Hi from a newbie member

PostPosted: Mon Jan 09, 2012 12:50 pm
by sully
I have had them working but i keep it to a absolute minimum it was 2-3 years ago when i last tested them all and they were all working fine. As you may or may not know with Modern computers eventually after use Main-boards fail.
These computers are 30 years old
So the less they are used the better for the long term.
What use is a original Jupiter ace if it has a blown main-board that can never be replaced?

Re: Hi from a newbie member

PostPosted: Mon Jan 09, 2012 3:18 pm
by Gibsaw
sully wrote:As you may or may not know with Modern computers eventually after use Main-boards fail... <snip> ...These computers are 30 years old So the less they are used the better for the long term.

Yeah, that's not strictly true. It's a bit more of a compromise than that. While it's true that some electrical/thermal fatigue does happen, most of the reasons a vintage machine dies are related to sheer age or disuse. Capacitors dry out.. Batteries leak... Motherboards delaminate.. Moisture gets into places that normally stay dry when a machine is in use..

The machines that are used and maintained regularly are the ones that stay going. Unless you've got some seriously controlled environment storage facilities, I'd switch on your machines regularly.. bring them up on a really good power conditioner, of course, if you're worried.
sully wrote:What use is a original Jupiter ace if it has a blown main-board that can never be replaced?

About the same as one that never gets switched on. Schrodinger's cat springs to mind. :)

Also, unless something absolutely catastrophic (like a lightning strike) happens, a "blown main-board" is usually fixable. It's usually a component fault, and very few IC's are truly "rare". (despite what the sellers on EBay would have you believe.) Actual "board faults" are rare and much more repairable than a modern 15 layer board with microscopic, surface mounted components.

Re: Hi from a newbie member

PostPosted: Mon Jan 09, 2012 3:32 pm
by tezza
Yes, that's right. I tend to be of the same school of thought as Gibsaw. From what I've read about these old machines it's good to give them a good spin once in a while. It keeps the capacitors fresh. In fact it's bad for the electronics to lie idle for too long. I generally regard something that's been off for 20 years as very likely broken if I'm looking at buying it.

I try to give all mine a full diagnostic check and a run for a few hours at least once a year, more regularly than that if I can. As distressing as it is when one occasionally fails (and they do sometimes), I can usually fix them and I like to have them in a state where if anyone visits, I can drag the unit out and show them just what a user would have seen in the day.

That said, individual collectors have different feelings on the matter. If you are happy to leave them off, that's entirely your preogative. Collectively, they certainly would be worth a bit, dead or alive.

(I haven't done any research on it but (given it's age) I'm assuming the Jupiter Ace would be relatively easy to fix? Apart from the ROM (which could probably be replaced with an EPROM), were any of the other chips proprietry? I'll have to Google it.)

Re: Hi from a newbie member

PostPosted: Mon Jan 09, 2012 3:49 pm
by Gibsaw
tezza wrote:(I haven't done any research on it but (given it's age) I'm assuming the Jupiter Ace would be relatively easy to fix? Apart from the ROM (which could probably be replaced with an EPROM), were any of the other chips proprietry? I'll have to Google it.)


Also, if the machine's rare, it pays to prepare for the inevitable. If I saw myself as one of the caretakers of this machine's future, and my main concern was longevity... then I would definitely be taking measures to mitigate any "rarity". i.e. Take dumps of the ROM's. Buy spares of standard chips. Get schematics & reference manuals. Find out what can be found out about any custom IC's that may be present.