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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: dudeslife on July 24, 2017, 03:13:25 AM

Title: Amiga 3000 w/ Dell ST2410 Issue
Post by: dudeslife on July 24, 2017, 03:13:25 AM
I picked up an Amiga 3000 and I am trying to use it with a Dell 2410 Monitor w/VGA but the screen is like "wavy"... not flickering.. Is there a solution or will this monitor not accept the 31hz? Any ideas? Thanks in advance. Giant Picture included. :)

(https://www.webho.net/pics/amiga3000.jpg )
Title: Re: Amiga 3000 w/ Dell ST2410 Issue
Post by: Oldsmobile_Mike on July 24, 2017, 03:15:57 AM
Doesn't the A3000 have an adjustment knob on the back for its 31KHz output?
Title: Re: Amiga 3000 w/ Dell ST2410 Issue
Post by: giZmo350 on July 24, 2017, 03:27:07 AM
@dudeslife

also, doesn't your camera and/or graphics app have an adjustment knob on the back to scale down that posted pic?  :hammer:
Title: Re: Amiga 3000 w/ Dell ST2410 Issue
Post by: Kremlar on July 24, 2017, 03:51:24 AM
Yes, adjust that knob with a small screwdriver carefully and slowly.
Title: Re: Amiga 3000 w/ Dell ST2410 Issue
Post by: dudeslife on July 24, 2017, 04:31:02 AM
Quote from: gizmo350;828618
@dudeslife

also, doesn't your camera and/or graphics app have an adjustment knob on the back to scale down that posted pic?  :hammer:


smaller pic would not have illustrated the issue as well...
Title: Re: Amiga 3000 w/ Dell ST2410 Issue
Post by: dudeslife on July 24, 2017, 04:37:24 AM
Quote from: Kremlar;828619
Yes, adjust that knob with a small screwdriver carefully and slowly.


ok thanks. I will check this out. would you happen to know clockwise or counter?
Title: Re: Amiga 3000 w/ Dell ST2410 Issue
Post by: Matt_H on July 24, 2017, 04:53:38 AM
Quote from: dudeslife;828621
ok thanks. I will check this out. would you happen to know clockwise or counter?


The official procedure is essentially "adjust it either way it until it looks right" :)

If you're getting resistance, don't force it - it probably means the screw has gone as far as it's meant to in that direction. Turn it back the other way.

A more worrisome possibility: battery leakage in the 3000 has been known to damage the video circuitry. Have you removed the battery?
Title: Re: Amiga 3000 w/ Dell ST2410 Issue
Post by: Oldsmobile_Mike on July 24, 2017, 05:04:19 AM
Quote from: gizmo350;828618
also, doesn't your camera and/or graphics app have an adjustment knob on the back to scale down that posted pic?  :hammer:

:laughing:

I still don't understand why people can't just use the built-in forum tools for attaching pictures to posts, neat and easy.  But eh, since when did Amiga users ever follow the rules?  :D
Title: Re: Amiga 3000 w/ Dell ST2410 Issue
Post by: dudeslife on July 24, 2017, 10:17:08 PM
Quote from: Matt_H;828622
The official procedure is essentially "adjust it either way it until it looks right" :)

If you're getting resistance, don't force it - it probably means the screw has gone as far as it's meant to in that direction. Turn it back the other way.

A more worrisome possibility: battery leakage in the 3000 has been known to damage the video circuitry. Have you removed the battery?

I am not seeing what kind of screw that is in the little hole next to the enable/disable switch.. flat or phillips head? and yes, I removed the battery but there was old corrosion there..

(https://www.webho.net/pics/batteryleak.jpg )
Title: Re: Amiga 3000 w/ Dell ST2410 Issue
Post by: Oldsmobile_Mike on July 24, 2017, 11:52:38 PM
Omg that is a terrific amount of battery damage!  :( :( :( :(

You need to get that thoroughly cleaned up and repaired before going any further.

Also from the picture you can see that your Denise chip isn't seated properly.

But FWIW, the screw is on the outside of the case, on the back, right next to the VGA connector.  Shine a flashlight in there if you have to.  See this picture:
Title: Re: Amiga 3000 w/ Dell ST2410 Issue
Post by: dudeslife on July 25, 2017, 02:00:28 AM
Quote from: Oldsmobile_Mike;828664
Omg that is a terrific amount of battery damage!  :( :( :( :(

You need to get that thoroughly cleaned up and repaired before going any further.

Also from the picture you can see that your Denise chip isn't seated properly.

But FWIW, the screw is on the outside of the case, on the back, right next to the VGA connector.  Shine a flashlight in there if you have to.  See this picture:


argh.. I live in the middle of nowhere as far as retro computers go.. I don't know how I am gonna get it repaired. do you think the denise chip not seated correctly would cause the wavyness of the video.

also that corrosion is 10 years old at least.. what can I do about that? alcohol and q-tips?
Title: Re: Amiga 3000 w/ Dell ST2410 Issue
Post by: QuikSanz on July 25, 2017, 02:28:43 AM
OMG! Get that board to Acil fast before it's toast!
Title: Re: Amiga 3000 w/ Dell ST2410 Issue
Post by: icbrkr on July 25, 2017, 02:38:01 AM
Holy crap.. that thing still fires up?  Yeah... get it fixed before it eats up everything there.

I'll bet something going to the Amber circuit has been eaten a bit.
Title: Re: Amiga 3000 w/ Dell ST2410 Issue
Post by: Matt_H on July 25, 2017, 03:00:06 AM
Quote from: dudeslife;828666
argh.. I live in the middle of nowhere as far as retro computers go.. I don't know how I am gonna get it repaired. do you think the denise chip not seated correctly would cause the wavyness of the video.

First step is to clean it up. Sometimes that can be enough. It looks like there's some corrosion in the Denise socket. Pop out the chip, clean, and put it back in. I don't think it's likely that Denise alone is the cause of your problems, but it's possible.

Quote
also that corrosion is 10 years old at least.. what can I do about that? alcohol and q-tips?


Yes, alcohol and q-tips. Acill (a user on this forum) can undertake more serious repairs if that ends up being necessary. I am assuming you are US-based. There are a few others around the world who do board repairs as well.
Title: Re: Amiga 3000 w/ Dell ST2410 Issue
Post by: QuikSanz on July 25, 2017, 03:43:37 AM
There looks to already be a leg eaten away on the bottom chip to the left of the battery spot. Send it in for complete once over.
Title: Re: Amiga 3000 w/ Dell ST2410 Issue
Post by: midway on July 25, 2017, 04:28:38 AM
Alcohol alone wont be enough. Vinegar to neutralize the battery liquid and once it stops bubbling you will have neutralized it. Castellen in new zealand is another option to repair.
Title: Re: Amiga 3000 w/ Dell ST2410 Issue
Post by: kirk_m on July 25, 2017, 02:42:46 PM
Goes without mentioning, but, after you've neutralized it with vinegar, and then cleaned all that residue off with 99% isopropyl, make sure you've left the board dry out for at least a day before powering it on, even though isopropyl evaporates quickly.
Title: Re: Amiga 3000 w/ Dell ST2410 Issue
Post by: Pat the Cat on July 25, 2017, 04:07:38 PM
Quote from: dudeslife;828662
I am not seeing what kind of screw that is in the little hole next to the enable/disable switch.. flat or phillips head? and yes, I removed the battery but there was old corrosion there..

(https://www.webho.net/pics/batteryleak.jpg )

Looks pretty bad, but if you are getting a picture from a booting machine, it's cosmetic damage rather than real damage. Lot of surface oxidation but the electrons are still able to travel in the right circuits.

The little adjustment knob is next to the switch on the back, flat head (preferably plastic) and be very gentle, you only need a few degrees rotation to get it right.

You are plugging in the monitor to the 15 pin VGA connector, right? The built in flicker fixer is connected to that, as I recall. The 23 pin connector Amiga video connector still runs at 15KHz no matter which way the switch is plugged.

The best substance I have found for de-oxidising old boards is... vitamin C. Ascorbic acid. A little stronger than acetic acid in vinegar.

Dissolved in boiling water, it eats oxides very effectively, good degreasing too. You do have to rinse it thoroughly afterwards though (more boiling water, then de-ionised water for final rinse).

Then, you can think about isopropyl alcohol. That's the best for final cleansing (it soaks up water) but it doesn't touch oxides and isn't that good at degreasing either.
 
 Leave a couple of days to dry out. You don't need a lot of cleaning liquids, and using cotton buds helps to keep cleaning agents to where they are needed. Even so, a wet board plugged into electricity will cause a helluva lot more damage than a leaky battery.
Title: Re: Amiga 3000 w/ Dell ST2410 Issue
Post by: dudeslife on July 25, 2017, 09:48:34 PM
Thanks everyone.. I think after I clean up the corrosion I am going to eBay it. I just don't have the time to give it the love it needs..
Title: Re: Amiga 3000 w/ Dell ST2410 Issue
Post by: giZmo350 on July 26, 2017, 06:26:06 AM
Thanks for the warning Dude!  :eek:

What's your eBay screen name so I can watch the auction!
Title: Re: Amiga 3000 w/ Dell ST2410 Issue
Post by: dudeslife on July 26, 2017, 08:02:22 PM
Quote from: gizmo350;828745
Thanks for the warning Dude!  :eek:

What's your eBay screen name so I can watch the auction!


I will fully disclose the damage but I wonder if it will generate any interest...
Title: Re: Amiga 3000 w/ Dell ST2410 Issue
Post by: SACC-guy on July 26, 2017, 11:18:43 PM
Quote from: dudeslife;828773
I will fully disclose the damage but I wonder if it will generate any interest...
sure it will..
AS long as it's working, (and cheap) it can still be repaired