Commodore A1200 RevB no video output.

seuden · 19 February 2010, 00:58

As title suggests.

Received an A1200 today with 340MB HDD and 8MB expansion with 4MB installed. I've just tried it with my tv and both the composite and (I think due to not being able to tune) the rf are not giving me a signal. I now the TV's are fine as I have another A1200 which works. I've checked inside (after taking of that poxy metal casing) and found no visual/physical evidence of anything wrong ie capacitors or leakage. It's been kindly suggested by Photon that it could be the denise chip, is that definitely the case (not that I'm questioning Photons intelligence

) or is there anything else I can check or do that may have been missed?

fitzsteve · 19 February 2010, 01:08

Quote:

Originally Posted by seuden

As title suggests.

Received an A1200 today with 340MB HDD and 8MB expansion with 4MB installed. I've just tried it with my tv and both the composite and (I think due to not being able to tune) the rf are not giving me a signal. I now the TV's are fine as I have another A1200 which works. I've checked inside (after taking of that poxy metal casing) and found no visual/physical evidence of anything wrong ie capacitors or leakage. It's been kindly suggested by Photon that it could be the denise chip, is that definitely the case (not that I'm questioning Photons intelligence

) or is there anything else I can check or do that may have been missed?

Does it work with the RGB output? My old A1200 stopped outputting video through the composite but the RGB still worked.

I know its not a fix but a workaround so you can at least use the Amiga.

Steve.

seuden · 19 February 2010, 01:28

I don't have an RGB lead

prowler · 19 February 2010, 01:31

I can let you have an A520 RGB to Composite and RF converter to test the RGB output with.

seuden · 19 February 2010, 09:42

Yes please prowler, how much?

prowler · 19 February 2010, 22:36

You don't have to buy it. You'd really get a much better display with an RBG to SCART lead.

I was thinking you could borrow my A520, just to test the Amiga's RGB output.

seuden · 20 February 2010, 09:43

Ah, if you don't mind that would be cool. Unless it's just easier for me to buy a RGB to scart lead?

fitzsteve · 20 February 2010, 12:20

Hi mate, an RGB Scart lead is well worth getting for the imporved picture quality over composite.

I just took some pics of the same WB Screen and Game on the same TV via the two different connections as a comparison, what the camera can't capture though is the increased flicker through composite

Anyway here ya go:

WB Composite

WB Scart

Game Composite

Game Scart

Steve.

edit... Hmm looking at the pics it doesent look to bad, but when you see the the two for real there is a huge improvment. (Look out for the shadowing on the composite)

cosmicfrog · 20 February 2010, 19:08

get a scart lead its loads better even if fitzsteve`s screens don`t show it, he should have done a few workbech pics for comparison

prowler · 20 February 2010, 21:15

Quote:

Originally Posted by seuden

Ah, if you don't mind that would be cool. Unless it's just easier for me to buy a RGB to scart lead?

Hi seuden,

Steve's right. It really is best to get an RGB to SCART lead. It just gives so much extra definition to the picture.

But that won't be any good if you can't get any video output from your Amiga's RGB Monitor connector and that's where the A520 will come in handy to let you test it first.

Now, I seem to have been sent the A600/A1200 floppy drive that you bought from ck1200 and you have been sent the A500+ floppy drive that I bought from him. He got them muddled up before putting the address labels on.

So, if I sent you the A520 with your A600/A1200 floppy drive, perhaps you could sent me the A500+ floppy drive with the A520 when you've finished with it. How does that sound?

fitzsteve · 20 February 2010, 21:32

Quote:

Originally Posted by cosmicfrog

get a scart lead its loads better even if fitzsteve`s screens don`t show it, he should have done a few workbech pics for comparison

You're right!

Here's a workbench comparison also:

Composite:

RGB Scart:

Steve.

Jope · 20 February 2010, 21:35

Blur and ghosting vs. no blur and ghosting.

Yet people still want to use composite and s-video and separate vga scalers..

Photon · 21 February 2010, 04:11

Just bought a pristine 1084S.

Just teasin ya

Certainly I suggest getting an RGB scart lead (and testing it on a RGB capable monitor!!). You won't get a better display, and there might be a chance that by connecting the 'unprocessed video output', you could get picture and any peripheral conversion like composite or RF wouldn't matter anymore.

If RGB output fails, I only see two options: Denise is bad or A1200 needs fixin'

But remember that you need to be sure your monitor accepts RGB, so connect your working A1200 to the monitor first to see that it does.

Did you test swapping the Denise in your working A1200 yet? Don't swap chips if the nondisplay A1200 doesn't seem to boot normally, ie doesn't boot from a known working floppy disk like a game or something.

seuden · 22 February 2010, 09:54

Thanks for the info guys.

That sounds like a plan prowler I'll pm you my address, thanks.

I'm sure the A1200 does boot normally, I'll double check tonight and if it does I'll try the denise out of my other A1200.

Thanks again peeps

prowler · 22 February 2010, 21:37

PM received and reply sent!

cosmicfrog · 22 February 2010, 22:11

just out of curiosity how are you takeing the denise out of my other A1200

seuden · 22 February 2010, 22:21

Quote:

Originally Posted by cosmicfrog

just out of curiosity how are you takeing the denise out of my other A1200

I have no idea, that was going to be my other question.

fitzsteve · 22 February 2010, 22:43

I'd wait till you've tested the RGB output before you start pulling chips... You'll probably need a proper chip remover, Amigakit sell one.

cosmicfrog · 22 February 2010, 23:08

they are soldered on in an a1200

PowerPie5000 · 22 February 2010, 23:49

Quote:

Originally Posted by cosmicfrog

they are soldered on in an a1200

They would be quite difficult to remove and even harder to re-solder if you lack soldering experience.

rkauer · 23 February 2010, 01:14

Quote:

Originally Posted by cosmicfrog

just out of curiosity how are you takeing the denise out of my other A1200

[PEDANTIC MODE]
Denise? On A1200?
[/PEDANTIC MODE]

cosmicfrog · 23 February 2010, 01:26

shhhh eveythings going to be all right just don`t mention the Lis word and fingers crosed rgb will be ok

prowler · 23 February 2010, 21:19

Hi seuden,

The A520 is on its way to you by first class post with your A600/A1200 floppy drive as well.

When you get the A520, simply plug it into the RGB video port of the A1200 and connect the Video Out socket to your TV via the composite video input. This provides the same picture you would get if the composite video socket of your Amiga was giving you a signal.

If this is successful, then your Amiga's RGB output is working normally. It gave a picture on my Amiga before I packed it this morning.

The A520 also provides a modulated RF output, but if its composite video output is not giving you a picture, then your Amiga's RGB video port is not providing a signal and neither will the A520's RF output.

Good luck with that.

If your Amiga's RGB video port is dead, then it sounds like you're in for a hard time.

seuden · 23 February 2010, 22:41

Hi prowler,

Thank you very much, I got kindly reminded by the missus that I have the rest of the week off work, lol, but I'll get a colleague to let me know when it arrives and I'll go and collect it. As soon as I give it a try I'll let you know the outcome and get the A520 and your floppy drive in first class post to you.

Again thank you.

seuden · 01 March 2010, 22:12

Hey peeps.

I've managed to test the RGB port on the A1200 and it works (a little temperamental but it works \o/ ). It's going to be a spare A1200 anyway.

The composite definitely doesn't work tho

Still, I'm probably going to purchase a RGB --> Scart as suggested, I may even try making one

Again, thanks for the help/suggestions from everyone.

Prowler, I have already packed the items and will post them tomorrow. Thanks again

prowler · 01 March 2010, 22:22

Hi Seuden,

That's great news about your RGB port.

If that's working, then the next logical step is an RGB to SCART cable.

It might be best to try making your own, because very often the ready-made ones don't work straight out of the box without a little rewiring.

If it would help, I'll upload details of the RGB-SCART lead I have for use with my Amigas for you tomorrow.

You can get round the need for a 23-pin D-type socket by hacking the much more common 25-pin type.

I'm now looking forward to receiving my A500+ floppy drive soon.

Thanks, mate!

seuden · 01 March 2010, 23:10

Quote:

Originally Posted by prowler

Hi Seuden,

That's great news about your RGB port.

Absolutely, I'm extremely pleased an A1200 isn't heading towards the bin just yet

Quote:

Originally Posted by prowler

If that's working, then the next logical step is an RGB to SCART cable.

It might be best to try making your own, because very often the ready-made ones don't work straight out of the box without a little rewiring.

If it would help, I'll upload details of the RGB-SCART lead I have for use with my Amigas for you tomorrow.

You can get round the need for a 23-pin D-type socket by hacking the much more common 25-pin type.

That would be awesome, yes please

Quote:

Originally Posted by prowler

I'm now looking forward to receiving my A500+ floppy drive soon.

Thanks, mate!

Np, thank you

rkauer · 02 March 2010, 00:46

Seems that the RGB to composite encoder bit the bullet for me.

prowler · 02 March 2010, 23:03

Hi seuden,

Here are the wiring details of the RGB-SCART lead I have for use with my Amigas. This lead is used with my A500s, A1200s and A4000 for display via either a CRT TV or Acorn TV monitor (Commodore 1084 type).

Code:

   SCART Plug Pin      To      Amiga Video Pin
   ~~~~~~~~~~~~~~      ~~      ~~~~~~~~~~~~~~~
 2 - Audio In (Right)           Right Audio Out
 4 - Audio Ground                    and
 6 - Audio In (Left)            White Audio Out
 7 - Blue In                    5 - Analog Blue
 8 - AV Mode         --|>|--   22 - +12 Volts DC
11 - Green In                   4 - Analog Green
15 - Red In                     3 - Analog Red
16 - Blanking        --|>|--   22 - +12 Volts DC
17 - Video Ground      ___     17 - Video Earth
20 - Video/Sync In  --|220|--  10 - Composite Sync

There are two 1N4148 signal diodes and a 220 Ohm resistor inside the SCART plug enclosure. The diodes are orientated with the black band towards the +12V.

Quote:

Originally Posted by rkauer

Seems that the RGB to composite encoder bit the bullet for me.

Is that a request for help, mate?

seuden · 02 March 2010, 23:20

Hi Prowler,

Thanks for the info, duly noted for future project

I'll let you know how I get on

20 February 2010, 19:08	#9
cosmicfrog The 1 who ribbits Join Date: Apr 2006 Location: leek, Staffs, UK Age: 45 Posts: 3,552	get a scart lead its loads better even if fitzsteve`s screens don`t show it, he should have done a few workbech pics for comparison __________________ When in dought RIBBIT .... If it dos`t work hit it with a hammer, if that dos`t work get a bigger hammer.......... Have U scen my sanity Pill`s . . . . . . . . . . . . . . // *This Years Software on Last Years Hardware \\//-- Amiga* --**

21 February 2010, 04:11	#13
Photon Oldskool Demo Coder Join Date: Nov 2004 Location: Hult / Sweden Age: 41 Posts: 3,674	Just bought a pristine 1084S. Just teasin ya Certainly I suggest getting an RGB scart lead (and testing it on a RGB capable monitor!!). You won't get a better display, and there might be a chance that by connecting the 'unprocessed video output', you could get picture and any peripheral conversion like composite or RF wouldn't matter anymore. If RGB output fails, I only see two options: Denise is bad or A1200 needs fixin' But remember that you need to be sure your monitor accepts RGB, so connect your working A1200 to the monitor first to see that it does. Did you test swapping the Denise in your working A1200 yet? Don't swap chips if the nondisplay A1200 doesn't seem to boot normally, ie doesn't boot from a known working floppy disk like a game or something. __________________ Henrik. Programs Amiga demos, iPhone apps, websites, etc. A1000/512k - A500 2.0/040@28/4M/.5M slowmem/8M/SCSI/CF - A600 portable II 3.1/ACA630/WiFi/CF - 'A1700' 3.1/68060@80/64M/IDE-Fix Express/CF - etc."The difference between PC and Amiga is that 10yo PCs are worth $0. 20yo Amigas are worth a lot, and Amigas that are only 15yo cost a fortune!" If you like Portal 2, try my >> single player and cooperation maps <<

22 February 2010, 22:11	#16
cosmicfrog The 1 who ribbits Join Date: Apr 2006 Location: leek, Staffs, UK Age: 45 Posts: 3,552	just out of curiosity how are you takeing the denise out of my other A1200 __________________ When in dought RIBBIT .... If it dos`t work hit it with a hammer, if that dos`t work get a bigger hammer.......... Have U scen my sanity Pill`s . . . . . . . . . . . . . . // *This Years Software on Last Years Hardware \\//-- Amiga* --**

22 February 2010, 22:43	#18
fitzsteve Professional slacker! Join Date: Jul 2009 Location: Kent, UK Age: 33 Posts: 4,736	I'd wait till you've tested the RGB output before you start pulling chips... You'll probably need a proper chip remover, Amigakit sell one. Last edited by fitzsteve; 22 February 2010 at 23:05.

22 February 2010, 23:08	#19
cosmicfrog The 1 who ribbits Join Date: Apr 2006 Location: leek, Staffs, UK Age: 45 Posts: 3,552	they are soldered on in an a1200 __________________ When in dought RIBBIT .... If it dos`t work hit it with a hammer, if that dos`t work get a bigger hammer.......... Have U scen my sanity Pill`s . . . . . . . . . . . . . . // *This Years Software on Last Years Hardware \\//-- Amiga* --**

19 February 2010, 01:31	#4
prowler Global Moderator Join Date: Aug 2008 Location: Sidcup, England Posts: 8,724	I can let you have an A520 RGB to Composite and RF converter to test the RGB output with.

19 February 2010, 22:36	#6
prowler Global Moderator Join Date: Aug 2008 Location: Sidcup, England Posts: 8,724	You don't have to buy it. You'd really get a much better display with an RBG to SCART lead. I was thinking you could borrow my A520, just to test the Amiga's RGB output.

20 February 2010, 12:20	#8
fitzsteve Professional slacker! Join Date: Jul 2009 Location: Kent, UK Age: 33 Posts: 4,736	Hi mate, an RGB Scart lead is well worth getting for the imporved picture quality over composite. I just took some pics of the same WB Screen and Game on the same TV via the two different connections as a comparison, what the camera can't capture though is the increased flicker through composite Anyway here ya go: WB Composite WB Scart Game Composite Game Scart Steve. edit... Hmm looking at the pics it doesent look to bad, but when you see the the two for real there is a huge improvment. (Look out for the shadowing on the composite)

20 February 2010, 21:35	#12
Jope - Join Date: Jul 2003 Location: Helsinki / Finland Age: 32 Posts: 4,061	Blur and ghosting vs. no blur and ghosting. Yet people still want to use composite and s-video and separate vga scalers..

22 February 2010, 21:37	#15
prowler Global Moderator Join Date: Aug 2008 Location: Sidcup, England Posts: 8,724	PM received and reply sent!

23 February 2010, 01:26	#22
cosmicfrog The 1 who ribbits Join Date: Apr 2006 Location: leek, Staffs, UK Age: 45 Posts: 3,552	shhhh eveythings going to be all right just don`t mention the Lis word and fingers crosed rgb will be ok __________________ When in dought RIBBIT .... If it dos`t work hit it with a hammer, if that dos`t work get a bigger hammer.......... Have U scen my sanity Pill`s . . . . . . . . . . . . . . // *This Years Software on Last Years Hardware \\//-- Amiga* --**

23 February 2010, 21:19	#23
prowler Global Moderator Join Date: Aug 2008 Location: Sidcup, England Posts: 8,724	Hi seuden, The A520 is on its way to you by first class post with your A600/A1200 floppy drive as well. When you get the A520, simply plug it into the RGB video port of the A1200 and connect the Video Out socket to your TV via the composite video input. This provides the same picture you would get if the composite video socket of your Amiga was giving you a signal. If this is successful, then your Amiga's RGB output is working normally. It gave a picture on my Amiga before I packed it this morning. The A520 also provides a modulated RF output, but if its composite video output is not giving you a picture, then your Amiga's RGB video port is not providing a signal and neither will the A520's RF output. Good luck with that. If your Amiga's RGB video port is dead, then it sounds like you're in for a hard time.

01 March 2010, 22:22	#26
prowler Global Moderator Join Date: Aug 2008 Location: Sidcup, England Posts: 8,724	Hi Seuden, That's great news about your RGB port. If that's working, then the next logical step is an RGB to SCART cable. It might be best to try making your own, because very often the ready-made ones don't work straight out of the box without a little rewiring. If it would help, I'll upload details of the RGB-SCART lead I have for use with my Amigas for you tomorrow. You can get round the need for a 23-pin D-type socket by hacking the much more common 25-pin type. I'm now looking forward to receiving my A500+ floppy drive soon. Thanks, mate!

02 March 2010, 00:46	#28
rkauer I hate potatos and shirts Join Date: Oct 2007 Location: Sao Leopoldo / Brazil Age: 47 Posts: 3,477	Seems that the RGB to composite encoder bit the bullet for me. __________________ Amigan since 1989 Known drunk since 1982 (don't know quite well, I was drunk) 13 Amigas at home Finally a Z3 one! I'll stick with 'Cachaça do Inter' for this week: Chivas gives headaches! :D

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Video and Sound doesnt match (video output)	hipoonios	support.WinUAE	8	26 July 2009 00:25
Bad video output	landex	support.Hardware	9	17 March 2008 04:16
Video output problem	P-J	support.WinUAE	2	19 November 2006 20:49
A1200 Video Output problem	EmuChicken	support.Hardware	17	19 September 2006 14:33
garbage video output on 1200	hardwir3d	support.Hardware	2	15 March 2005 12:11