28 February 2021, 13:56 | #1 |
Registered User
Join Date: Nov 2005
Location: Newark / UK
Posts: 108
|
A600 colour strange over RGB
Hi everybody!
I've recently set up my a600 that was recapped by RetroPassion just before Christmas. I now have a strange colour issue over Rgb to scart that I didn't have before. Colours over composite look OK. Can anyone give me a starting place to look at? Attached are two images one over Rgb scart the other composite. Thanks! |
28 February 2021, 14:11 | #2 |
Registered User
Join Date: May 2016
Location: Mandeville USA
Posts: 203
|
I had a 1200 that was outputting video that was too bright. I fixed it by following the info in this blog (replacing the reference voltage diode):
https://www.tsb.space/knowledge-base...-video-signal/ |
28 February 2021, 14:14 | #3 |
Registered User
Join Date: Dec 2018
Location: UK
Posts: 1,716
|
Looks like the blue colour not getting through - so look at the schematics and amigapcb.org (for rev 2A) to check the traces/pins/components associated with it.
https://www.amigawiki.org/doku.php?i...chematics#a600 |
28 February 2021, 17:37 | #4 |
Registered User
Join Date: Nov 2005
Location: Newark / UK
Posts: 108
|
Thanks all for suggestions so far.
I have found this video [ Show youtube player ] Which shows a repair for loss of red. Using this and the advice above I hope I will find a solution. |
28 February 2021, 18:27 | #5 |
Registered User
Join Date: Oct 2012
Location: Krypton
Posts: 1,214
|
Have you tried another RGB cable ?, as some of them are poorly made and wires in the 23 pin hood can come loose and short out especialy if the lead is loose/floppy where it actually enters the hood, I know because it has happend to me
|
28 February 2021, 18:39 | #6 |
Thalion Webshrine
Join Date: Jan 2004
Location: Oxford
Posts: 14,355
|
Does it flicker when the HDD, PCMCIA or FDD is being used? mine is like that. It's not caps.
|
28 February 2021, 18:55 | #7 |
Registered User
Join Date: Nov 2005
Location: Newark / UK
Posts: 108
|
Have tried the cable on my a500 and a1200 without problems.
Don't recall any flickering. Picture is quite steady, just wrong colour! |
28 February 2021, 19:08 | #8 |
Registered User
Join Date: Nov 2005
Location: Newark / UK
Posts: 108
|
I have just noticed in the picture attached that I think I have a component missing!
Perhaps this was removed during the recap and never replaced? I think this is on the blue line to the rgb connector Can anyone advise where I could get this transistor from in the UK? |
28 February 2021, 19:34 | #9 |
Registered User
Join Date: Aug 2020
Location: Torquay
Posts: 166
|
Yes Q233 should be there and is related to the blue signal on the RGB output so that'll be your problem. The picture below shows it in place on an A600, ignore the missing caps, it's in the middle of being recapped. It's a standard off the shelf transistor, an NPN 2N3904 SOT23, depending on your soldering skills you may not enjoy the job of soldering a new one on.
It probably came off when the caps were being removed, and if he tested it afterwards with composite may not have noticed. I am sure if you talk to Steve at Retro Passion he will sort you out. |
02 March 2021, 11:57 | #10 |
Registered User
Join Date: Nov 2005
Location: Newark / UK
Posts: 108
|
Have ordered the required transistor and will attempt my first surface mount soldering!
|
02 March 2021, 21:35 | #11 |
Registered User
Join Date: Aug 2020
Location: Torquay
Posts: 166
|
|
02 March 2021, 22:05 | #12 |
Registered User
Join Date: Nov 2005
Location: Newark / UK
Posts: 108
|
The results of my soldering are so bad that I refuse to share. But it worked! See attached. Thanks all for their advice.
Last edited by ikorodu; 03 March 2021 at 08:04. |
02 March 2021, 22:32 | #13 |
Registered User
Join Date: Aug 2020
Location: Torquay
Posts: 166
|
|
Currently Active Users Viewing This Thread: 1 (0 members and 1 guests) | |
Thread Tools | |
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
A600 - No Blue Colour on RGB | PARALAX | support.Hardware | 17 | 24 June 2022 17:53 |
3.1 ROM on A600 - 4 Colour workbench | Toryglen-boy | support.Apps | 4 | 23 February 2017 00:52 |
Strange a600 | BEX | support.Hardware | 4 | 27 May 2016 20:43 |
Strange A600 behaviour | Gavilan | support.Hardware | 9 | 08 July 2009 19:02 |
A600 display lacking colour? | Fingerlickin_B | support.Hardware | 63 | 02 May 2008 01:07 |
|
|