ZXpand+ video interference

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rkindig
Posts: 17
Joined: Mon Apr 02, 2018 5:54 am

ZXpand+ video interference

Post by rkindig »

Hi,

I'm pretty new to the TS1000. I have a ZX-keyboard and ZXpand+ attached. With just the TS1000 and no upgrades, or with the ZX-Keyboard attached, the video is ok. However, with the ZXpand+ installed I get what looks like interference (dark bands). Is that normal? It's not severe and I can still see and use the computer, but there's definite interference going on.

thanks

Randy
Lardo Boffin
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Re: ZXpand+ video interference

Post by Lardo Boffin »

Its not unusual for plugging something in to affect the picture. The more complex the peripheral the greater the effect it is likely to have. The ‘spand+ has RAM, replaces the ROM, has an SD card reader and does sound!

Mark explained why in one of the threads (possibly in my sparkly pixel thread).
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1024MAK
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Re: ZXpand+ video interference

Post by 1024MAK »

rkindig wrote: Sat Dec 26, 2020 9:12 pm However, with the ZXpand+ installed I get what looks like interference (dark bands).
I would say it’s not normal.

The topic that Lardo is referring to is here. There’s lots of interesting posts, but you have to skip to the last page is see what fixed it!

With yours, could you please take a photo of the video picture and post it up here so we can see what the symptoms look like?

Simple things to try and some questions:
  • Have you cleaned the edge-connector / expansion port contacts?
  • Do you have another PSU to try with it?
  • If you are not using a Timex/Sinclair PSU, but are using another type, do you have a Timex/Sinclair PSU to try it with?
  • Is this symptom there from power on, or does it happen as the computer warms up?
  • How are you connecting the TV/monitor? TV RF / aerial or composite video? If the latter, which method of composite video?
  • Do you have a RAM pack? If yes, does it work okay with this?
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rkindig
Posts: 17
Joined: Mon Apr 02, 2018 5:54 am

Re: ZXpand+ video interference

Post by rkindig »

Wow lots of things to try!

I will test all the recommended things and configurations here and get back with the group.

I do not have a composite mod on this TS1000. I’m using the TV RF and the interference shows up immediately. Also I’m using the power supply that came with the TS1000.

Thanks!

Randy
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