Search found 119 matches

by Muttley Black
Fri Nov 05, 2021 9:52 am
Forum: Hardware
Topic: Zx spectrum 128 +2 iss3 Z70500, problem with tr9
Replies: 14
Views: 812

Re: Zx spectrum 128 +2 iss3 Z70500, problem with tr9

Finally I got some time :)

I made some tests.

1) volts on pin 11 of TEA2000 is 11,4V. I also gave my self 12+ and nothing change.

2) Pins 12 / 13 have correct MHz.

3) Taking directly video signal from pin 6 didn’t change anything. No color.

4) Pin 14 is High.

I am lost…….. :)
by Muttley Black
Tue Oct 05, 2021 8:25 am
Forum: Hardware
Topic: Zx spectrum 128 +2 iss3 Z70500, problem with tr9
Replies: 14
Views: 812

Re: Zx spectrum 128 +2 iss3 Z70500, problem with tr9

Thank you so much for your help! I have this pdf already printed. Just no much free time. I will post when I have news! :)
by Muttley Black
Wed Sep 29, 2021 4:07 pm
Forum: Hardware
Topic: Zx spectrum 128 +2 iss3 Z70500, problem with tr9
Replies: 14
Views: 812

Re: Zx spectrum 128 +2 iss3 Z70500, problem with tr9

Yes. Two monitors. Monitors that working great with other spectrum computers.
by Muttley Black
Wed Sep 29, 2021 2:50 pm
Forum: Hardware
Topic: Zx spectrum 128 +2 iss3 Z70500, problem with tr9
Replies: 14
Views: 812

Re: Zx spectrum 128 +2 iss3 Z70500, problem with tr9

I have the same scope with you! Also all my measurements are about the same with you. I don’t understand why I don’t have a color. I have made an av mod by get the signal from rgb connector. Everything is good but black and white picture only… I have test also 2 more tea2000. Same results.
by Muttley Black
Mon Sep 27, 2021 9:53 pm
Forum: Hardware
Topic: Zx spectrum 128 +2 iss3 Z70500, problem with tr9
Replies: 14
Views: 812

Re: Zx spectrum 128 +2 iss3 Z70500, problem with tr9

Thank you so much!!!

I will report back! :)
by Muttley Black
Sun Sep 26, 2021 7:04 am
Forum: Hardware
Topic: Zx spectrum 128 +2 iss3 Z70500, problem with tr9
Replies: 14
Views: 812

Re: Zx spectrum 128 +2 iss3 Z70500, problem with tr9

Hello and thank you for your answer. If it is no problem i want for all (not the voltage pins ofc) cause I want to compare with my results.

Thank you very much.
by Muttley Black
Fri Sep 17, 2021 12:15 pm
Forum: Hardware
Topic: Zx spectrum 128 +2 iss3 Z70500, problem with tr9
Replies: 14
Views: 812

Re: Zx spectrum 128 +2 iss3 Z70500, problem with tr9

Hello all.

Anyone have measurements of TEA2000 ic with oscilloscope?

With new ic still have no colors. :|
by Muttley Black
Thu Sep 16, 2021 9:18 am
Forum: Hardware
Topic: Zx spectrum 128 +2 iss3 Z70500, problem with tr9
Replies: 14
Views: 812

Re: Zx spectrum 128 +2 iss3 Z70500, problem with tr9

The problem was in 12v rail, that was short to ground and blows TR9. The solution made by replacing capacitors C6 and C41. Measurements on this two capacitors shows the one as resistor and the other one as diode. After that replacements voltages are ok. The only problem now is that TEA2000 color enc...
by Muttley Black
Mon Sep 06, 2021 6:16 pm
Forum: Hardware
Topic: Zx spectrum 128 +2 iss3 Z70500, problem with tr9
Replies: 14
Views: 812

Zx spectrum 128 +2 iss3 Z70500, problem with tr9

Hello all!

I have here a zx 128 +2 Issue3 Z70500 motherboard that didn’t have 12v. I measure TR9 ztx650 and it was faulty. I replace it with ztx651 but keeps burn it. I see in my desk power supply that pulls almost 2A when i connect the motherboard. I replace also tr8 with ztx751.

Any help please?
by Muttley Black
Wed Nov 25, 2020 11:39 am
Forum: Hardware
Topic: Arduino 4116 tester FINAL! Free Gerbers.
Replies: 2
Views: 5794

Arduino 4116 tester FINAL! Free Gerbers.

Hello! Here is my final 4116 tester. You can have all files from the link bellow. Including: Part List, gerber files, arduino code, driver for clone arduino Testing time: 11sec~ You can power the arduino from 9v dc power supply or from arduino usb (9v dc from power supply preferred) Download: http:/...
by Muttley Black
Thu Sep 03, 2020 1:43 pm
Forum: Hardware
Topic: Arduino 4116 Dram tester with an extrenal help.
Replies: 20
Views: 14242

Re: Arduino 4116 Dram tester with an extrenal help.

There was some errors in the prototype PCB. I did some emergency cable jumpers to solve the problem. Now it is ready and 100% in working order. Sadly I need to order some new pcb’s for the final test. This tester work also with 5 volts, through the Arduino usb plug. This future make it a bit portabl...
by Muttley Black
Sun Jul 26, 2020 2:33 am
Forum: Hardware
Topic: Arduino 4116 Dram tester with an extrenal help.
Replies: 20
Views: 14242

Re: Arduino 4116 Dram tester with an extrenal help.

Waiting the damn inductors to arrive.... :roll:

Image
by Muttley Black
Mon Jul 06, 2020 10:16 pm
Forum: Hardware
Topic: Arduino 4116 Dram tester with an extrenal help.
Replies: 20
Views: 14242

Re: Arduino 4116 Dram tester with an extrenal help.

Almost done! :D

I am waiting some more components to arrive.

Image
by Muttley Black
Sat Jun 27, 2020 7:51 pm
Forum: Hardware
Topic: The Startek DT-90 Project.
Replies: 14
Views: 2360

Re: The Startek DT-90 Project.

Here are the two Pal's i need to find or replace with Gal's: AMD 16L8B-2 PAL & AMD 16R4A-4 PAL.

If anyone have them in stock or can help with replacement ones, please post here.

Thank you
by Muttley Black
Fri Jun 26, 2020 12:00 pm
Forum: Hardware
Topic: The Startek DT-90 Project.
Replies: 14
Views: 2360

Re: The Startek DT-90 Project.

The first PCB’s just arrived. A long trip just started till the end. Need to check the board compared to schematic and get the components. :)

Anyone have a PAL programmer?

Image
by Muttley Black
Sun May 31, 2020 8:41 am
Forum: Hardware
Topic: Arduino 4116 Dram tester with an extrenal help.
Replies: 20
Views: 14242

Re: Arduino 4116 Dram tester with an extrenal help.

The prototype pcb's has not yet arrived, but i decided to do some changes for the final version. I reduced the board size. From 12cm x 11cm it was, it came to be a little less than 10cm x 10cm. This is because the cost of its construction is significantly reduced, but also for reasons of space savin...
by Muttley Black
Sat May 16, 2020 10:07 pm
Forum: Hardware
Topic: The Startek DT-90 Project.
Replies: 14
Views: 2360

Re: The Startek DT-90 Project.

Τhe actual photos are found but are from a later version. https://i.postimg.cc/YL0bCDX2/image1.jpg https://i.postimg.cc/wy0wHYQb/image0.jpg From my research, the only person i know who has one Startek DT-90, is one guy from the USA who repairs arcade machines. Is the same guy if i am not mistaken wh...
by Muttley Black
Fri May 15, 2020 12:35 pm
Forum: Hardware
Topic: The Startek DT-90 Project.
Replies: 14
Views: 2360

Re: The Startek DT-90 Project.

I always check the schematic but keep in mind that do checks on a copy pcb from the "pcb design program" and the schematic it is a pain. I am about 99% sure that the board i make is a good copy and i order some to check them. When they come i put the pcb and schematic front of me and i che...
by Muttley Black
Fri May 15, 2020 6:54 am
Forum: Hardware
Topic: The Startek DT-90 Project.
Replies: 14
Views: 2360

Re: The Startek DT-90 Project.

Good morning.

The purple pic it is the top view and only.

More later cause I am at work and from mobile.
by Muttley Black
Thu May 14, 2020 10:33 am
Forum: Hardware
Topic: The Startek DT-90 Project.
Replies: 14
Views: 2360

Re: The Startek DT-90 Project.

Board now finished.

I need to do double checks before the printing process. It is not really matter if this try fail. We always have a second chance.
It was a pleasure for me to recreate that board.

We will see...


Image
by Muttley Black
Wed May 13, 2020 10:26 pm
Forum: Hardware
Topic: The Startek DT-90 Project.
Replies: 14
Views: 2360

Re: The Startek DT-90 Project.

I would be very happy if somehow find a clear photo from both pcb sides, even with the components. That old and not so well pcb prints from the magazine makes my project a bit tricky. What i mean by that? If you look at the pcb mask, the one that have the components layout, LED4 (green/red) with the...
by Muttley Black
Wed May 13, 2020 4:57 am
Forum: Hardware
Topic: The Startek DT-90 Project.
Replies: 14
Views: 2360

Re: The Startek DT-90 Project.

Thank you for your great tutorial’s. I use Kicad. To be honest I start using Kicad in my 4116 tester, I don’t know if you saw it in hardware section. About Pal’s the code is available too and this ic’s can be found. I don’t have Pal programmer but when this time come and all I need is that, I ask fo...