ZXpand+ compatibility with TS-1500

[FrancoisLanciault]

Hi,

Maybe it is common knowledge, but I was wondering if the ZXpand+ would work on a TS-1500.

I know there is a issue with the zxPand being in the way of the connectors at the back but, that aside, would it work ? Specially how would it reacted to the fact that the TS-1500 comes with 16k RAM ? Would it replace/ignore the internal RAM ? Or add it to its own 32k making a 48k ZX Or would it hang, or catch fire ?


François

[Moggy]

I currently have a loaned TS-1500 and I have no problems using the ZXpand with it other than those you mention.

[FrancoisLanciault]

Ok thanks! Will try as soon as my rear connector expansion board comes in.

François

[Spinnetti]

Yep, works fine, I have it on mine. I did a composite mod and put the rca jack out the left side to resolve the blocked port on the back

[FrancoisLanciault]

I received my bus expansion board. But in my case, the TS-1500 does not work with the ZXpand+, no cursor, no display.

I tested the ZXpand+ with the same bus expansion board on my zx81, and it works, so that rules out the bus expansion…

Ideas ? Insufficient power supply ? (Same power supply was used in the test) Special ZXapnd+ configuration needed ?

François

[Lardo Boffin]

Is the edge connector inside the TS1500 clean?

[Moggy]

No special set up needed for the TS1500 and spand+.

I am running my TS1500 and spand+ as I type this and the only thing different I'm doing when using with normal ZX81 is that I have had to switch my power supply up to a slightly higher level.

My supply for this particular ZX81 and spand+ is an unregulated type which runs at just over 8.5 volts off load but I have to set it to nearer 13volts to use with the TS1500 other wise I get a blank screen, so perhaps that could be your problem.

[FrancoisLanciault]

Hi again,

I have moved the TS-1500 to the lab and hooked it to a bench power supply. The power supply was set to exactly 9V and current limit to 2 Amps.

When attached to the supply the equipment draws the following current:

ZX-81 1K : 350mA
ZX-81 + zx-pand : 550mA
TS-1500 : 550mA
TS-1500+zx-pand: 790mA

But still no image on screen

So we can see that the zx-pand+ draws current but something is not right because the computer stalls. Normal that it draws a little more current than when installed on the zx-81 ?

I can probe all line of the rear connector easily with the bus expansion, but I don’t know want to look for.

Francois

[FrancoisLanciault]

Hey, you were right!

Boosting to voltage of the bench power supply just to 10V did the trick!

It seems the voltage regulator in the TS-1500 needs a bit more than 9 volts to supply the need of both TS-15000 + zx-pand+.

Thanks!
François

No special set up needed for the TS1500 and spand+.

I am running my TS1500 and spand+ as I type this and the only thing different I'm doing when using with normal ZX81 is that I have had to switch my power supply up to a slightly higher level.

My supply for this particular ZX81 and spand+ is an unregulated type which runs at just over 8.5 volts off load but I have to set it to nearer 13volts to use with the TS1500 other wise I get a blank screen, so perhaps that could be your problem.

[Spinnetti]

Save some headaches and swap out the 7805 for a buck converter?