CZ1500 (TS1500) reverse engineering?

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dessony
Posts: 342
Joined: Tue Oct 29, 2013 2:26 pm
Location: Indiana, USA

CZ1500 (TS1500) reverse engineering?

Post by dessony »

Bola_dor,

Can you do reverse engineering on the CZ1500 and draw a schematic? Then post it here.

Thanks,
DesSony
bola_dor
Posts: 398
Joined: Wed Oct 02, 2019 5:32 am

Re: CZ1500 (TS1500) reverse engineering?

Post by bola_dor »

dessony wrote: Sat Feb 20, 2021 3:38 am Bola_dor,

Can you do reverse engineering on the CZ1500 and draw a schematic? Then post it here.

Thanks,
DesSony
Oh. I missed this out :(
I am sorry about answering so late..

CZ1500 were made of completely original parts from Timex Portugal. These were late board designs with the ram layout and the internal power supply being different as these don't use the 4116 any more..
Argentina uses (still) PAL-N for air broadcast TV, so this are 50Hz, similar to TS sold at Portugal but different from that's from the USA. The RF Modulator may be different then..
I can't do a reverse ingeniering by my self but can provide anything you need to if it is into my possibilities..
20200724_175354 (1) (1).jpg
20210309_074740.jpg
Ernesto
ZX80 USA, ZX81UK, ZX Spectrum, ZX Spectrum+, ZX Spectrum 128+ UK, ZX Spectrum +2/A, Sinclair QL, CZ1000, CZ1500, CZ2000, CZ1000Plus, CZ1500Plus, CZ Spectrum, CZ Spectrum Plus, TK83, TK85, TK90X, TK95. TS2068. And more to come :D
McKlaud
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Location: St Albans, UK

Re: CZ1500 (TS1500) reverse engineering?

Post by McKlaud »

Hi,

Your CZ1500 is the same like any late TS1500. The main difference is that there is a blob of solder on the 50Hz SELECT jumper. Looking at your photos I can say that the RF modulator is NTSC type like in my American TS1500.

You can easily modify this machine to the composite video output. Such modification requires a single NPN transistor and a jumper across D1 and R7.
Last edited by McKlaud on Tue Mar 09, 2021 4:47 pm, edited 1 time in total.
Claudius
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bola_dor
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Re: CZ1500 (TS1500) reverse engineering?

Post by bola_dor »

McKlaud wrote: Tue Mar 09, 2021 2:05 pm Hi,

Your CZ1500 is the same like any late TS1500. The main difference is that there is a blob of solder on the 50Hz SELECT jumper. Looking at your photos I can say that the RF modulator is NTSC type like in mine America TS1500.

You can easily modify this machine to the composite video output. Such modification requires a single NPN transistor and a jumper across D1 and R7.
All ready done!!
viewtopic.php?f=7&t=3771

RF is a thing about VHF vs UHF I think .
The solder bridge is about telling the ULA to make 50Hz Sync...
Ernesto
ZX80 USA, ZX81UK, ZX Spectrum, ZX Spectrum+, ZX Spectrum 128+ UK, ZX Spectrum +2/A, Sinclair QL, CZ1000, CZ1500, CZ2000, CZ1000Plus, CZ1500Plus, CZ Spectrum, CZ Spectrum Plus, TK83, TK85, TK90X, TK95. TS2068. And more to come :D
McKlaud
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Location: St Albans, UK

Re: CZ1500 (TS1500) reverse engineering?

Post by McKlaud »

Oh, I am so sorry, I didn't know. I can see CZ1500 works well. So, have a lot of fun with the machine.
Claudius
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bola_dor
Posts: 398
Joined: Wed Oct 02, 2019 5:32 am

Re: CZ1500 (TS1500) reverse engineering?

Post by bola_dor »

McKlaud wrote: Tue Mar 09, 2021 6:13 pm Oh, I am so sorry, I didn't know. I can see CZ1500 works well. So, have a lot of fun with the machine.
Don't have to be sorry :D
Yes it's very Fun indeed.. !!!
Ernesto
ZX80 USA, ZX81UK, ZX Spectrum, ZX Spectrum+, ZX Spectrum 128+ UK, ZX Spectrum +2/A, Sinclair QL, CZ1000, CZ1500, CZ2000, CZ1000Plus, CZ1500Plus, CZ Spectrum, CZ Spectrum Plus, TK83, TK85, TK90X, TK95. TS2068. And more to come :D
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1024MAK
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Location: Looking forward to summer in Somerset, UK...

Re: CZ1500 (TS1500) reverse engineering?

Post by 1024MAK »

4264 DRAM chips are 16k x 4 bits, hence you only need two for a 8 bit processor :D

And they only need a single +5V power supply :D

The various different TV/video standards do cause confusion.

First, there is the number of lines, and the line and field rates.

You can have either the 625 line, 15625Hz horizontal, 50Hz vertical system, or you can have the 525 line, 15750Hz horizontal, 60Hz vertical system (monochrome specifications, the 525 system frequencies are slightly different if using the NTSC colour system). In fact there are also other monochrome standards, but these all went obsolete a long time ago. All these are for monochrome video.

Then you can add colour encoding if you wish. Both PAL and the NTSC colour system can be used with either of the above systems. Let me clear on this, a 525 line system using PAL colour encoding is possible, as is a 625 line system using NTSC colour encoding.

Then there is the transmission frequency range. Any of the above systems can be broadcast on either the VHF or the UHF wavebands. The U.K. just choose not to use VHF for the 625 line system (the older 405 line system did use the VHF wavebands).

I hope you are keeping count of how many variations are possible...

There are other differences that can be added, but I think you get the idea...

Mark
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bola_dor
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Re: CZ1500 (TS1500) reverse engineering?

Post by bola_dor »

Thank you Mark..
As clear as water.. !
Ernesto
ZX80 USA, ZX81UK, ZX Spectrum, ZX Spectrum+, ZX Spectrum 128+ UK, ZX Spectrum +2/A, Sinclair QL, CZ1000, CZ1500, CZ2000, CZ1000Plus, CZ1500Plus, CZ Spectrum, CZ Spectrum Plus, TK83, TK85, TK90X, TK95. TS2068. And more to come :D
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