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General Category => NC100, NC200, PCW, PDA600 - the rest of the Family! => Topic started by: caver99 on 18:21, 26 August 20

Title: dead pcw 8512
Post by: caver99 on 18:21, 26 August 20
i've been using my pcw 8152 for a few hours now playing with basic.
i downloaded some games on to my gotek and been trying them out then i loaded ace but when i went to reset the pcw i had to switch it off as
the normal reset didnt work, so i pressed the power button and turned it off then back on again, selected another image on my gotek and it loaded
as it should but the sceen didnt power back up
so i have a working system but no screen, the tube powers up at the rear on the neck but its dead.
any idea anyone what could be the cause.
i've not recapped anything yet but it seems to be on the hot side of the board as the low voltage side still works as the main pcw board is powering and running.
Title: Re: dead pcw 8512
Post by: P5ychoFox on 08:20, 27 August 20
It may be a power board issue but first I'd try re-inserting all the floppy cables and ensure the black ground cable is attached to the power board. I've had PCWs do weird things like this with a loose cable. That said, I have also had a power board die too.
Title: Re: dead pcw 8512
Post by: caver99 on 12:03, 27 August 20
they have all been checked and removed and reinstalled but still the same and with checking it looks like the lopt might have given up the ghost as it has deat shorts which they shouldnt have as far as i can tell so looks like im buggered.
i ant find a replacement part anywhere or even an equivelent
or hopefully the STK7308 which you can get replacements for which i will test shortly
im so gutted now
Title: Re: dead pcw 8512
Post by: caver99 on 12:28, 27 August 20
further checking it maybe the STK7308 as low reading on the transformer it feeds and c5005 is low
Title: Re: dead pcw 8512
Post by: caver99 on 18:24, 03 September 20
ive replaced [size=0px]STK7308 but the screen is still dead.[/size]
[/size][size=0px]ive checked and double checked and even removed floppy cables including power so just power board and screen and main pcw board are connected.[/size]
[/size][size=0px]the heaters on back of screen power up but tube doesnt[/size]
[/size]
Title: Re: dead pcw 8512
Post by: Bryce on 18:58, 03 September 20
Can you feel any static charge on the surface of the screen? If not, the LOPT has failed.

Bryce.
Title: Re: dead pcw 8512
Post by: PCWPIP on 20:34, 09 November 20
There have been several attempts to consolise the PCW.  A hack exists to output to an external screen.
Title: Re: dead pcw 8512
Post by: JonB on 11:38, 16 November 20
A hack? Ha ha!

In this thread I explain to user radu14m how he can connect the PCW to a composite monitor using a video mixer I designed. The PCBs are tiny as can be seen, and are designed to plug directly onto the PCW's main board connector. Please review this thread - there are pictures of the board, how it is fitted to the PCW and of it working.

https://www.cpcwiki.eu/forum/nc100-nc200-pcw-pda600/pcw-wont-start-anymore/msg165254/#msg165254

I may be able to supply the bare board for you to build. Not sure I have any left. If not, however, I'll upload it to OSHPark and you can order a set of 3 for small money. Send me a PM if interested.

Cheers
JonB
Title: Re: dead pcw 8512
Post by: robcfg on 13:33, 16 November 20
Don't forget Habi's wonderful PCW-IO board! http://www.habisoft.com/pcwwiki/doku.php?id=es:hardware:perifericos:pcw-io
Title: Re: dead pcw 8512
Post by: PCWPIP on 23:30, 16 November 20
Perhaps 'hack' is the wrong word....'upgrade' is I think better?   ;D


If my monitor ever fails I would use one of these in a heartbeat.


Habi's board is rather impressive too.
Title: Re: dead pcw 8512
Post by: P5ychoFox on 19:28, 21 December 20
Quote from: Bryce on 18:58, 03 September 20
Can you feel any static charge on the surface of the screen? If not, the LOPT has failed.

Bryce.

I have an 8256 which has good fuses but no power, no static, no neck glow. Does this sound like a failed LOPT too? Thanks.
Title: Re: dead pcw 8512
Post by: Bryce on 19:59, 21 December 20
Is there any power on the PCB?

Bryce.
Title: Re: dead pcw 8512
Post by: P5ychoFox on 15:17, 22 December 20
Quote from: Bryce on 19:59, 21 December 20
Is there any power on the PCB?

Bryce.

I was just checking for any voltages when the computer came to life. It had been on for about a minute with no signs of life but then started up. I wonder if it's a capacitor issue and a minute's charging up is all it needed. It's ok for now but without regular use it'll probably go dead again.
Title: Re: dead pcw 8512
Post by: Bryce on 15:30, 22 December 20
More likely a dry joint or a dodgy connector.

Bryce.
Title: Re: dead pcw 8512
Post by: Sebastian Blanco on 19:02, 22 December 20
Converting the tiny board to run using any composite monitor was easyer than reparing my other dead 8256 at least for me.


https://www.cpcwiki.eu/forum/nc100-nc200-pcw-pda600/finally-got-my-spare-pcw-8256-board-installed-in-a-case/ (https://www.cpcwiki.eu/forum/nc100-nc200-pcw-pda600/finally-got-my-spare-pcw-8256-board-installed-in-a-case/msg169203/#msg169203)



https://ibb.co/Yh9gkzz
Title: Re: dead pcw 8512
Post by: P5ychoFox on 14:57, 27 December 20
Quote from: Bryce on 18:58, 03 September 20
Can you feel any static charge on the surface of the screen? If not, the LOPT has failed.

Bryce.

Thanks, this makes sense. I'll check all the joints, especially around high temperature components.
Title: Re: dead pcw 8512
Post by: P5ychoFox on 15:00, 27 December 20
Quote from: Sebastian Blanco on 19:02, 22 December 20
Converting the tiny board to run using any composite monitor was easyer than reparing my other dead 8256 at least for me.


https://www.cpcwiki.eu/forum/nc100-nc200-pcw-pda600/finally-got-my-spare-pcw-8256-board-installed-in-a-case/ (https://www.cpcwiki.eu/forum/nc100-nc200-pcw-pda600/finally-got-my-spare-pcw-8256-board-installed-in-a-case/msg169203/#msg169203)



https://ibb.co/Yh9gkzz

Very nice solution. I did something similar a while back and put an 8256 with Gotek into a CPC 6128 case. It's on YouTube somewhere.
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