Timex Sinclair 1000 power supply polarity?

[Roger Blake]

I picked up an old Timex Sinclair 1000 computer from a thrift store
recently. It came with a 16K RAM pack, but no power supply. The power
jack looks like a 1/8" earphone jack and is marked "9V" -- but no
polarity is indicated. I don't want to fry this thing, anyone know
what the polarity is supposed to be on this thing? (I've done some
web searches and not found the answer yet...)

 

[NoSp]

I don't want to fry this thing, anyone know
what the polarity is supposed to be on this thing?

I suggest you track down someone else with a Timex Sinclair 1000 who
will hopefully read the polarity diagram from its power supply, or has a
multimeter handy in order to check.
Contacting the guy behind this page for instance may give some positive
results: http://www.vidgame.net/timex/timex.htm

eBay may be another place to look. Find someone selling one, and kindly
ask if he/she can check the polarity.
Other than that, spend some time searching the web for "Timex Sinclair
1000", even if it doesn't have the word "polarity" in it.
Good luck!

 

[Roger Blake]

Contacting the guy behind this page for instance may give some positive
results: http://www.vidgame.net/timex/timex.htm

Thanks for the lead, I'll fire him off a note...

 

[N_Cook]

I picked up an old Timex Sinclair 1000 computer from a thrift store
recently. It came with a 16K RAM pack, but no power supply. The power
jack looks like a 1/8" earphone jack and is marked "9V" -- but no
polarity is indicated. I don't want to fry this thing, anyone know
what the polarity is supposed to be on this thing? (I've done some
web searches and not found the answer yet...)

spam.)

I would take it apart and trace the wiring to any diodes or regulators.
If I remember back that far, Sinclair had a habit of using 9V ac.
9V or so DC will usually work , either way round in this situation, but you
need to get an idea of the current as well.
9V ac supply onto a requiremnent for 9V dc will not work

Was Timex the brand name given for Sinclair stuff sold in the States ?

 

[Adrian C]

I picked up an old Timex Sinclair 1000 computer from a thrift store
recently.

(I've done some

web searches and not found the answer yet...)

Must attend google school? Site found looking for "ZX81 schematic"
<http://www.mainbyte.com/ts1000/man.html>

Check here, trace the connections to C3 and the regulator.
<http://www.mainbyte.com/ts1000/good_schematic_hi.jpg>

 

[NoSp]

Must attend google school? Site found looking for "ZX81 schematic"
<http://www.mainbyte.com/ts1000/man.html>

I read (http://oldcomputers.net/ts1000.html) that there were some slight
differences between the TS1000 and the ZX-81 which also included the
circuit board.
I'd physically inspect the traces from the power connector or wait for
information from someone else who has a TS1000 instead of risking damage.

 

[Roger Blake]

I'd physically inspect the traces from the power connector or wait for
information from someone else who has a TS1000 instead of risking damage.

I had someone respond via email who said that the plug tip is positive.

Not sure how tough these are to open but if possible I'll verify by
looking at the connections inside.

 

[Adrian C]

Adrian C wrote:

I read (http://oldcomputers.net/ts1000.html) that there were some slight
differences between the TS1000 and the ZX-81 which also included the
circuit board.

The schematic I pointed out has the US/UK differences marked. Video
stuff. The site it's on is dedicated to the TS1000.

I'd physically inspect the traces from the power connector

Yup, the UK drives on the wrong side of the road, so it's possible that
the connector polarity had originally been wired the wrong way up as
well :-|

Nope, just kidding - The French would do that. For the OP, the web site
has a ZX81 assembly manual. Section 9 gives details of the power supply
and polarity required. <http://www.mainbyte.com/ts1000/install_man.html>

 

[Aurel Boisvert]

The TS1000/Sinclair ZX81 are not protected with a diode.
The 9VDC goes directly to the 7805 voltage regulator.

 

[Roger Blake]

9. POWER SUPPLY
If you wish to use your own power supply with the ZX81, it should conform to these specifications -
D.C. only -positive to the tip of the 3.5mm jack plug. Need not be regulated, but should be well
smoothed.
...

Thanks -- though the result is kind of anticlimactic since after hooking
up a decent power supply as specified, this particular TS1000 appears
to be dead as a doornail. I'll open it up and check it out when I have time...

 

[[email protected]]

Thanks -- though the result is kind of anticlimactic since after hooking
up a decent power supply as specified, this particular TS1000 appears
to be dead as a doornail. I'll open it up and check it out when I have time...

I've used this approach on occaision and its worked. Connect the UUT
to a variable power supply. Slowly advance the voltage while keeping a
sharp eye on the current. If the current seems to begin to rise
disproportionately, then you probably have the supply reversed. Lenny.

 

[mike]

I've used this approach on occaision and its worked. Connect the UUT
to a variable power supply. Slowly advance the voltage while keeping a
sharp eye on the current. If the current seems to begin to rise
disproportionately, then you probably have the supply reversed. Lenny.

fwiw,
You can use an ohm-meter to determine which of the power pins is connected
do some other system ground/connector shield etc.
The other pin is often, but not always the + pin.
It's a good guess if no other info is available.
mike

 

[Roger Blake]

You can use an ohm-meter to determine which of the power pins is connected
do some other system ground/connector shield etc.
The other pin is often, but not always the + pin.
It's a good guess if no other info is available.

Thanks for the tip. Though it seems I'm having nothing but bad luck
with old computers at the moment. I also have an "Interact" 8080-based
"home computer" that I purchased around 1980 or so. Decided to fire it
up to check out some of the old games, and the thing appears to have
cratered. For those not familiar with this somewhat obscure system,
some info can be found here:

http://www.old-computers.com/MUSEUM/computer.asp?c=1004

Bummer, it's been about a year since firing this thing up and it worked
perfectly last time!

The Interact is powered by a wall wart that puts out multiple AC voltages
with the rest of the power supply located inside the main unit. These
computers were pretty notorious for blowing out voltage regulators, will
have to check and see if that's the case here...

 

[Curtis Brown]

I picked up an old Timex Sinclair 1000 computer from a thrift store
recently. It came with a 16K RAM pack, but no power supply. The power
jack looks like a 1/8" earphone jack and is marked "9V" -- but no
polarity is indicated. I don't want to fry this thing, anyone know
what the polarity is supposed to be on this thing? (I've done some
web searches and not found the answer yet...)

What do you care if you fry the motherfucker or not? I mean what can you
possibly do with the motherfucker?

Something like

10 PRINT "once upon a time, there was this girl named ashleigh cope,"
20 PRINT "and michael terrell bent her over his kitchen counter,"
30 PRINT "and put his penis in her vagina, and she liked it."
40 GOTO 10

 

[Bill]

What do you care if you fry the motherfucker or not? I mean what can you
possibly do with the motherfucker?

Something like

10 PRINT "once upon a time, there was this girl named ashleigh cope,"
20 PRINT "and michael terrell bent her over his kitchen counter,"
30 PRINT "and put his penis in her vagina, and she liked it."
40 GOTO 10

Hey, dipshit Brown,
You can do a hell of a lot if your wise assed big mouth knows how to
program in real assembly and translate it to actual machine code.
A friend of mine bought a lot of 50 of them and drove his wife nuts
wiring a keypad to every thing electronic that broke. Washing machine,
refrigerator, and everything else. They happen to be neat little
controllers and use very little power.
You madame Curtiss are the butt of you own crap. Do you honestly believe
anyone would want a 3GHz super chip just to control the rinse cycles on
the dryer?
One word....STOOOPID.
Bill Baka

 

[Curtis Brown]

Hey, dipshit Brown,

HEY DIPSHIP KAKA

You can do a hell of a lot if your wise assed big mouth knows how to
program in real assembly and translate it to actual machine code.

I could learn if there is a practical use for it like it would land me a 6
figure job.

A friend of mine bought a lot of 50 of them and drove his wife nuts wiring
a keypad to every thing electronic that broke. Washing machine,
refrigerator, and everything else.

Now if only your friend would **** his wife once in a while...

They happen to be neat little controllers and use very little power.

No, they happen to be garbage that nobody with a life would want to have
anything to do with.

You madame Curtiss are the butt of you own crap. Do you honestly believe
anyone would want a 3GHz super chip just to control the rinse cycles on
the dryer?

Just buy a modern dryer and it would have it's own chip to control it's own
rinse cycles.

One word....STOOOPID.
Bill Baka

Five Words....GO SUCK CHUCKII BOOKER'S DICK

Curtis Brown

 

[gimechip]

9VDC Center Positive 1-AMP

9VDC Center Positive 1-AMP is the proper power supply. I see it's already been answered, but I was wondering if anyone could answer the following question:
Does anyone know where I can get a schematic of the TS1500 (Timex Sinclair 1500)? I've just repaired one, but one lead of coil L4 is broken loose and I don't know where to reattach it. The interesting thing about this machine is that several of the 4116's were bad, and the mask ROM was blank (contained all $FF's - I burned an eprom and replaced the mask ROM with that.) After replacing a couple of the 4116's and replacing the ROM the machine works great, but I don't want to leave the lead of L4 unconnected - a schematic would be great. The one from TS1000.us would be great, but it's not there anymore (ts1500schematic.pdf) - I can't find it anywhere. Any help would be greatly appreciated. -Robert