So then, with only 0.08V out from the 9V power supply, I'm guessing it doesn't work yet.Lardo Boffin wrote: ↑Fri May 28, 2021 1:58 pm Plugged in and switched on - no explosions! Also very little voltage at the 9V plug by the zeddy. About 0.08 so not much going to happen there!
Hey ho.
‘Tatung 81’ (ZX81 in a case)
Re: ‘Tatung 81’ (ZX81 in a case)
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Re: ‘Tatung 81’ (ZX81 in a case)
Sadly not. I will remove the zeddy from the case and try that. Hopefully that will be ok then it is just a matter of deciding what to do about the PSU.BarryN wrote: ↑Fri May 28, 2021 4:15 pmSo then, with only 0.08V out from the 9V power supply, I'm guessing it doesn't work yet.Lardo Boffin wrote: ↑Fri May 28, 2021 1:58 pm Plugged in and switched on - no explosions! Also very little voltage at the 9V plug by the zeddy. About 0.08 so not much going to happen there!
Hey ho.
ZX80
ZX81 iss 1 (bugged ROM, kludge fix, normal, rebuilt)
TS 1000 iss 3, ZXPand AY and +, ZX8-CCB, ZX-KDLX & ChromaSCART
Tatung 81 + Wespi
TS 1500 & 2000
Spectrum 16k (iss 1 s/n 862)
Spectrum 48ks plus a DIVMMC future and SPECTRA
ZX81 iss 1 (bugged ROM, kludge fix, normal, rebuilt)
TS 1000 iss 3, ZXPand AY and +, ZX8-CCB, ZX-KDLX & ChromaSCART
Tatung 81 + Wespi
TS 1500 & 2000
Spectrum 16k (iss 1 s/n 862)
Spectrum 48ks plus a DIVMMC future and SPECTRA
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- Posts: 2169
- Joined: Sat Nov 26, 2016 2:42 am
Re: ‘Tatung 81’ (ZX81 in a case)
In amongst the box of stuff I also found this lot:
ZX80
ZX81 iss 1 (bugged ROM, kludge fix, normal, rebuilt)
TS 1000 iss 3, ZXPand AY and +, ZX8-CCB, ZX-KDLX & ChromaSCART
Tatung 81 + Wespi
TS 1500 & 2000
Spectrum 16k (iss 1 s/n 862)
Spectrum 48ks plus a DIVMMC future and SPECTRA
ZX81 iss 1 (bugged ROM, kludge fix, normal, rebuilt)
TS 1000 iss 3, ZXPand AY and +, ZX8-CCB, ZX-KDLX & ChromaSCART
Tatung 81 + Wespi
TS 1500 & 2000
Spectrum 16k (iss 1 s/n 862)
Spectrum 48ks plus a DIVMMC future and SPECTRA
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- Posts: 2169
- Joined: Sat Nov 26, 2016 2:42 am
Re: ‘Tatung 81’ (ZX81 in a case)
And
ZX80
ZX81 iss 1 (bugged ROM, kludge fix, normal, rebuilt)
TS 1000 iss 3, ZXPand AY and +, ZX8-CCB, ZX-KDLX & ChromaSCART
Tatung 81 + Wespi
TS 1500 & 2000
Spectrum 16k (iss 1 s/n 862)
Spectrum 48ks plus a DIVMMC future and SPECTRA
ZX81 iss 1 (bugged ROM, kludge fix, normal, rebuilt)
TS 1000 iss 3, ZXPand AY and +, ZX8-CCB, ZX-KDLX & ChromaSCART
Tatung 81 + Wespi
TS 1500 & 2000
Spectrum 16k (iss 1 s/n 862)
Spectrum 48ks plus a DIVMMC future and SPECTRA
- 1024MAK
- Posts: 5118
- Joined: Mon Sep 26, 2011 10:56 am
- Location: Looking forward to summer in Somerset, UK...
Re: ‘Tatung 81’ (ZX81 in a case)
Aren’t you supposed to connect up to a nuclear power station first?Lardo Boffin wrote: ↑Fri May 28, 2021 1:58 pm Plugged in and switched on - no explosions! Also very little voltage at the 9V plug by the zeddy. About 0.08 so not much going to happen there!
Hey ho.
So have you checked those fuses? Obviously with the power off, use the continuity range or the resistance range.
Next up, just unplug the 9V power jack plug and use a normal Sinclair PSU...
OR, power up the existing power supply and test the voltage across the leads of both of the large electrolytic capacitors. But do be careful to keep clear of the mains wiring, fuses and connections.
Mark
ZX81 Variations
ZX81 Chip Pin-outs
ZX81 Video Transistor Buffer Amp
Standby alert
There are four lights!
Step up to red alert. Sir, are you absolutely sure? It does mean changing the bulb
Looking forward to summer later in the year.
ZX81 Chip Pin-outs
ZX81 Video Transistor Buffer Amp
Standby alert
There are four lights!
Step up to red alert. Sir, are you absolutely sure? It does mean changing the bulb
Looking forward to summer later in the year.
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- Posts: 2169
- Joined: Sat Nov 26, 2016 2:42 am
Re: ‘Tatung 81’ (ZX81 in a case)
I’m legal not allowed to go near power stations…1024MAK wrote: ↑Fri May 28, 2021 6:27 pmAren’t you supposed to connect up to a nuclear power station first?Lardo Boffin wrote: ↑Fri May 28, 2021 1:58 pm Plugged in and switched on - no explosions! Also very little voltage at the 9V plug by the zeddy. About 0.08 so not much going to happen there!
Hey ho.
So have you checked those fuses? Obviously with the power off, use the continuity range or the resistance range.
Next up, just unplug the 9V power jack plug and use a normal Sinclair PSU...
OR, power up the existing power supply and test the voltage across the leads of both of the large electrolytic capacitors. But do be careful to keep clear of the mains wiring, fuses and connections.
Mark
I checked the fuses with the continuity setting and both are fine. I will check the zeddy at some point.
When I’m feeling brave I will check the caps voltage. I managed to a fit a BuzzOff to my Vectrex without killing myself so hopefully will be ok!
ZX80
ZX81 iss 1 (bugged ROM, kludge fix, normal, rebuilt)
TS 1000 iss 3, ZXPand AY and +, ZX8-CCB, ZX-KDLX & ChromaSCART
Tatung 81 + Wespi
TS 1500 & 2000
Spectrum 16k (iss 1 s/n 862)
Spectrum 48ks plus a DIVMMC future and SPECTRA
ZX81 iss 1 (bugged ROM, kludge fix, normal, rebuilt)
TS 1000 iss 3, ZXPand AY and +, ZX8-CCB, ZX-KDLX & ChromaSCART
Tatung 81 + Wespi
TS 1500 & 2000
Spectrum 16k (iss 1 s/n 862)
Spectrum 48ks plus a DIVMMC future and SPECTRA
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- Posts: 2169
- Joined: Sat Nov 26, 2016 2:42 am
Re: ‘Tatung 81’ (ZX81 in a case)
The zeddy and keyboard work fine! Picture is pretty good as well.
ZX80
ZX81 iss 1 (bugged ROM, kludge fix, normal, rebuilt)
TS 1000 iss 3, ZXPand AY and +, ZX8-CCB, ZX-KDLX & ChromaSCART
Tatung 81 + Wespi
TS 1500 & 2000
Spectrum 16k (iss 1 s/n 862)
Spectrum 48ks plus a DIVMMC future and SPECTRA
ZX81 iss 1 (bugged ROM, kludge fix, normal, rebuilt)
TS 1000 iss 3, ZXPand AY and +, ZX8-CCB, ZX-KDLX & ChromaSCART
Tatung 81 + Wespi
TS 1500 & 2000
Spectrum 16k (iss 1 s/n 862)
Spectrum 48ks plus a DIVMMC future and SPECTRA
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- Posts: 2169
- Joined: Sat Nov 26, 2016 2:42 am
Re: ‘Tatung 81’ (ZX81 in a case)
Maybe this is the home my rebuilt zeddy has been looking for?….
ZX80
ZX81 iss 1 (bugged ROM, kludge fix, normal, rebuilt)
TS 1000 iss 3, ZXPand AY and +, ZX8-CCB, ZX-KDLX & ChromaSCART
Tatung 81 + Wespi
TS 1500 & 2000
Spectrum 16k (iss 1 s/n 862)
Spectrum 48ks plus a DIVMMC future and SPECTRA
ZX81 iss 1 (bugged ROM, kludge fix, normal, rebuilt)
TS 1000 iss 3, ZXPand AY and +, ZX8-CCB, ZX-KDLX & ChromaSCART
Tatung 81 + Wespi
TS 1500 & 2000
Spectrum 16k (iss 1 s/n 862)
Spectrum 48ks plus a DIVMMC future and SPECTRA
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- Posts: 2169
- Joined: Sat Nov 26, 2016 2:42 am
Re: ‘Tatung 81’ (ZX81 in a case)
Found a spare ZX81 (minus case) in the box with the Tatung 81 - in a bag cunningly labelled ‘Replacement mainboard’ (check out the bent heatsink!). No K initially but after some chip swapping it is up and running. The Z80 had died - I’m pretty sure I have had more dead Z80’s than ULAs now.
The heatsink on the ULA is of course nothing to do with me! I guess in the context of the size of the case it made some sense.
The heatsink on the ULA is of course nothing to do with me! I guess in the context of the size of the case it made some sense.
ZX80
ZX81 iss 1 (bugged ROM, kludge fix, normal, rebuilt)
TS 1000 iss 3, ZXPand AY and +, ZX8-CCB, ZX-KDLX & ChromaSCART
Tatung 81 + Wespi
TS 1500 & 2000
Spectrum 16k (iss 1 s/n 862)
Spectrum 48ks plus a DIVMMC future and SPECTRA
ZX81 iss 1 (bugged ROM, kludge fix, normal, rebuilt)
TS 1000 iss 3, ZXPand AY and +, ZX8-CCB, ZX-KDLX & ChromaSCART
Tatung 81 + Wespi
TS 1500 & 2000
Spectrum 16k (iss 1 s/n 862)
Spectrum 48ks plus a DIVMMC future and SPECTRA
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- Posts: 2169
- Joined: Sat Nov 26, 2016 2:42 am
Re: ‘Tatung 81’ (ZX81 in a case)
It is rather large!
ZX80
ZX81 iss 1 (bugged ROM, kludge fix, normal, rebuilt)
TS 1000 iss 3, ZXPand AY and +, ZX8-CCB, ZX-KDLX & ChromaSCART
Tatung 81 + Wespi
TS 1500 & 2000
Spectrum 16k (iss 1 s/n 862)
Spectrum 48ks plus a DIVMMC future and SPECTRA
ZX81 iss 1 (bugged ROM, kludge fix, normal, rebuilt)
TS 1000 iss 3, ZXPand AY and +, ZX8-CCB, ZX-KDLX & ChromaSCART
Tatung 81 + Wespi
TS 1500 & 2000
Spectrum 16k (iss 1 s/n 862)
Spectrum 48ks plus a DIVMMC future and SPECTRA