Astro City shadow near the letters

For monitor related issues
User avatar
grantspain
Tech Head
Posts: 4823
Joined: August 17th, 2008, 4:23 pm
Location: down south

Re: Astro City shadow near the letters

Post by grantspain »

pointless me answering any of these posts anymore
Firehawk
Posts: 34
Joined: May 20th, 2020, 12:53 pm
Location: The Netherlands
eBay: firehawkgrb

Re: Astro City shadow near the letters

Post by Firehawk »

@nem no I can't, I have the mvs mv1b which is very hard to install an unibios to. And this NeoBiosMasta is hard to get.
But a Naomi board is on the way maybe it has a better service menu.

@grantspain Haha, no feel free to comment if you have additional tips and trick what can be done.
User avatar
grantspain
Tech Head
Posts: 4823
Joined: August 17th, 2008, 4:23 pm
Location: down south

Re: Astro City shadow near the letters

Post by grantspain »

i have already told you the fault, the new neck card should resolve the fault
Firehawk
Posts: 34
Joined: May 20th, 2020, 12:53 pm
Location: The Netherlands
eBay: firehawkgrb

Re: Astro City shadow near the letters

Post by Firehawk »

Thanks for all the help.
When I have received and installed the replacement neck board I will post back the results if it solved the issue.
User avatar
Sp33dFr34k
Posts: 277
Joined: December 3rd, 2011, 12:27 pm
Location: The Netherlands
eBay: 3d_collector

Re: Astro City shadow near the letters

Post by Sp33dFr34k »

@grantspain he can't keep the new neckboard, if the new one works fine I will replace the zener diode on the old one and see if that works. So it's a 15v one, how many watts should it be? Should this one work?

https://www.reichelt.nl/zener-diode-5-0 ... _pdn&nbc=1
User avatar
grantspain
Tech Head
Posts: 4823
Joined: August 17th, 2008, 4:23 pm
Location: down south

Re: Astro City shadow near the letters

Post by grantspain »

Sp33dFr34k wrote: June 4th, 2020, 1:14 pm @grantspain he can't keep the new neckboard, if the new one works fine I will replace the zener diode on the old one and see if that works. So it's a 15v one, how many watts should it be? Should this one work?

https://www.reichelt.nl/zener-diode-5-0 ... _pdn&nbc=1
it 500mw i think, its very small
User avatar
Sp33dFr34k
Posts: 277
Joined: December 3rd, 2011, 12:27 pm
Location: The Netherlands
eBay: 3d_collector

Re: Astro City shadow near the letters

Post by Sp33dFr34k »

grantspain wrote: June 4th, 2020, 1:39 pm
Sp33dFr34k wrote: June 4th, 2020, 1:14 pm @grantspain he can't keep the new neckboard, if the new one works fine I will replace the zener diode on the old one and see if that works. So it's a 15v one, how many watts should it be? Should this one work?

https://www.reichelt.nl/zener-diode-5-0 ... _pdn&nbc=1
it 500mw i think, its very small
Thanks Grant, will order one of those then :)
User avatar
Sp33dFr34k
Posts: 277
Joined: December 3rd, 2011, 12:27 pm
Location: The Netherlands
eBay: 3d_collector

Re: Astro City shadow near the letters

Post by Sp33dFr34k »

Okay, so we've just replaced the neckboard with another one. It seemed to be slightly better, however the damn thing burned out after a few minutes. Put back the original neckboard which still works, though of course with the same issue. @grantspain which diodes do we need to replace exactly for the rgb lines? Would that be D321/D322/D323?

Additional question; if it's not the diodes, what else could it be?
User avatar
grantspain
Tech Head
Posts: 4823
Joined: August 17th, 2008, 4:23 pm
Location: down south

Re: Astro City shadow near the letters

Post by grantspain »

why would a neck board burn out?
you need to get this to someone who knows how to fix it
Firehawk
Posts: 34
Joined: May 20th, 2020, 12:53 pm
Location: The Netherlands
eBay: firehawkgrb

Re: Astro City shadow near the letters

Post by Firehawk »

Like Sp33dFr34k said. The replacement neckboard did work.
Suddenly the monitor stopped working and it smelled burned. When we turned the cabinet on again we saw a red glowing burning dot at the back of the neckboard near a yoke pin connection. Quickly turned it off again.
Removed the neckboard and soldered my old neckboard to it again and this keeps working. But of course with the same issue. That's why we want to know where we have to replace the transistors.

The replacement board is also very dirty and black.
On the second link I marked with a red circle where it burned.

https://drive.google.com/file/d/1UhIQVk ... p=drivesdk

https://drive.google.com/file/d/1UcYw2m ... p=drivesdk

Also the replacement neckboard did work for a few minutes but had the same issue. Slightly less we believe but still.
User avatar
Sp33dFr34k
Posts: 277
Joined: December 3rd, 2011, 12:27 pm
Location: The Netherlands
eBay: 3d_collector

Re: Astro City shadow near the letters

Post by Sp33dFr34k »

grantspain wrote: June 21st, 2020, 9:50 pm why would a neck board burn out?
you need to get this to someone who knows how to fix it
Trust me, I know my way around a soldering iron, not sure what happened to the neckboard. But it wasn't the cleanest looking one as can be seen in the pictures.

I'd like to try to replace the diodes on the original neckboard, if you could point me to the correct one(s), that would be much appreciated.
User avatar
grantspain
Tech Head
Posts: 4823
Joined: August 17th, 2008, 4:23 pm
Location: down south

Re: Astro City shadow near the letters

Post by grantspain »

they are marked zd, make sure 10uf 250v cap is replaced
i am sure you are ok with a soldering iron
User avatar
Sp33dFr34k
Posts: 277
Joined: December 3rd, 2011, 12:27 pm
Location: The Netherlands
eBay: 3d_collector

Re: Astro City shadow near the letters

Post by Sp33dFr34k »

grantspain wrote: June 22nd, 2020, 8:39 am they are marked zd, make sure 10uf 250v cap is replaced
i am sure you are ok with a soldering iron
Thanks a lot Grant, found them now, ZD301/ZD311/ZD321. Will replace those and the cap when I'm over there again and post back here.
Firehawk
Posts: 34
Joined: May 20th, 2020, 12:53 pm
Location: The Netherlands
eBay: firehawkgrb

Re: Astro City shadow near the letters

Post by Firehawk »

Ok so replaced the 3 diodes and also the cap.
Gladly the monitor still works :D
But unfortunately the problem still persist. Is it still a neckboard problem then?

Here some pictures, you still see the shadows. In these pictures I turned the brightness to full so you can see it better.

https://drive.google.com/file/d/1WDbVAm ... p=drivesdk

https://drive.google.com/file/d/1WDimA4 ... p=drivesdk

https://drive.google.com/file/d/1WE8H4p ... p=drivesdk
User avatar
nem
Needs a custom rank
Posts: 2768
Joined: August 17th, 2008, 6:59 pm
Location: Finland

Re: Astro City shadow near the letters

Post by nem »

I'm still sticking to it that it's a weak tube. You're overdriving the contrast to make up for it and that will result in the shadow.
Firehawk
Posts: 34
Joined: May 20th, 2020, 12:53 pm
Location: The Netherlands
eBay: firehawkgrb

Re: Astro City shadow near the letters

Post by Firehawk »

Thanks for your reply.
What does that mean. It can't be fixed? Only replacing the tube is the solution?
User avatar
nem
Needs a custom rank
Posts: 2768
Joined: August 17th, 2008, 6:59 pm
Location: Finland

Re: Astro City shadow near the letters

Post by nem »

I had great results rejuvenating both of my MS8-29 Tosh tubes. I've probably put 2000 hours on them afterwards, they still look bright and vibrant. Ask around locally if anyone has a rejuvenator you could borrow. König is a German brand that manufactured a line of 'CRT Analyzers' that are common in Europe.

Also, before I forget, check the resistors near the diodes on the neckboard. There's one resistor for every diode. I seem to remember if the diode goes the resistor blows as well. Just so you can be sure it's not the neck board.
User avatar
grantspain
Tech Head
Posts: 4823
Joined: August 17th, 2008, 4:23 pm
Location: down south

Re: Astro City shadow near the letters

Post by grantspain »

i reckon its a chassis fault
Firehawk
Posts: 34
Joined: May 20th, 2020, 12:53 pm
Location: The Netherlands
eBay: firehawkgrb

Re: Astro City shadow near the letters

Post by Firehawk »

Thanks for the answers.

@grantspain Where do I have to look first or replace all the cap?
Firehawk
Posts: 34
Joined: May 20th, 2020, 12:53 pm
Location: The Netherlands
eBay: firehawkgrb

Re: Astro City shadow near the letters

Post by Firehawk »

I just started my cab and now the monitor is not working anymore :wtf:
Yesterday it worked the whole evening.

The sound and light is working from the cab only no picture on the monitor.
I made a video. When I give it power it wants to start and then you hear a click and it's over.
WHen I turn the cab of after a minute or so you hear a sound like it's releasing some electric or something.
It doesn't smell burned or see any smoke.
I checked the neckboard and reflowed my solderjob but it has no effect.

Video
https://drive.google.com/file/d/1WZZ7di ... sp=sharing

Also at the back of the neckboard you see some solderpads are bridged this was already the case when I got it. Anyone know what that means.
https://drive.google.com/file/d/1WZ0hzd ... sp=sharing
Post Reply