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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: Lurch on December 19, 2012, 09:39:47 AM

Title: Removed E123C and E125C now no picture
Post by: Lurch on December 19, 2012, 09:39:47 AM
So after testing my A1200 1d4 with my new ACA 1231 I'd get the occasional yellow flashing screen and freezing in WHDload and the odd strange error with WHDLoad.

Thought okay I'll try the timing fix from http://www.ianstedman.co.uk/Amiga/amiga_hacks/A1200_Mobo_fix/a1200_mobo_fix.html

Doh mistake, removed E123C and E125C and now there is no picture.

First thing I did notice before doing it was the circled components in the screen shot were E123R and E125C.. but thought this might be a mistake so removed the E123C and E125C as per the text... doh doh...

Anyway I'm thinking if someone has a 1200 motherboard and preferably local with timing fixes in place and you want to sell ;-)
Title: Re: Removed E123C and E125C now no picture
Post by: RedskullDC on December 19, 2012, 10:21:45 AM
Hi Lurch,

Quote from: Lurch;719653


Thought okay I'll try the timing fix from http://www.ianstedman.co.uk/Amiga/amiga_hacks/A1200_Mobo_fix/a1200_mobo_fix.html

Doh mistake, removed E123C and E125C and now there is no picture.

First thing I did notice before doing it was the circled components in the screen shot were E123R and E125C.. but thought this might be a mistake so removed the E123C and E125C as per the text... doh doh...

Anyway I'm thinking if someone has a 1200 motherboard and preferably local with timing fixes in place and you want to sell ;-)


E123C and E125C are what *should* be removed according to the official fixes.
See the accompanying pic for a clip from the 1200 schematics.
In reality, it doesn't matter if you remove either the resistors or capacitors, since
they are both in series to ground.

I'd be checking for any solder blobs you may have left behind...
If the pads of E123C are shorted together for example, you'll have no 7MHz clock signal :(
(27 ohms shorted to ground would be enough to pull it permanently low.)

Hope this helps,
Red
Title: Re: Removed E123C and E125C now no picture
Post by: Lurch on December 19, 2012, 10:24:27 AM
Hmm can't see it touching. Will have another look :-/
Title: Re: Removed E123C and E125C now no picture
Post by: magnetic on December 19, 2012, 11:06:11 AM
Sorry to hear about that.. Send it to Amigakit for repair. Chances are FOL can fix it.
Title: Re: Removed E123C and E125C now no picture
Post by: Lurch on December 19, 2012, 05:36:03 PM
Yep sad days, poor girl. Will do sometime next year, no point sending anything at the moment. Especially from New Zealand :-/
Title: Re: Removed E123C and E125C now no picture
Post by: Lurch on December 19, 2012, 08:20:34 PM
Decided to send it off now, paid for the timing fix and sent :-/
Title: Re: Removed E123C and E125C now no picture
Post by: NovaCoder on December 20, 2012, 01:32:05 AM
Tell them to change the CAPS while they have it (might as well kill two birds and all that).
Title: Re: Removed E123C and E125C now no picture
Post by: mechy on December 20, 2012, 02:39:15 AM
Quote from: Lurch;719660
Hmm can't see it touching. Will have another look :-/

Lurch,
 Anthony(castellan on here) is in your back yard! he could of fixed it for you for sure.
he does some fine amiga repairs in NZ.
Title: Re: Removed E123C and E125C now no picture
Post by: Lurch on December 20, 2012, 04:27:35 AM
Quote from: mechy;719762
Lurch,
 Anthony(castellan on here) is in your back yard! he could of fixed it for you for sure.
he does some fine amiga repairs in NZ.



Who's this Anthony you speak of? Damn I've just sent it off :-(  LOL

I'll have to remember him for next time :-) Thanks Mechv, wish there was a list of repairers somewhere.
Title: Re: Removed E123C and E125C now no picture
Post by: Kitch on December 20, 2012, 04:37:00 AM
Anthony was in our back yard but at the moment he's down in Antarctica until November next year. I've already got a couple of repair's saved up for when he gets back.
Title: Re: Removed E123C and E125C now no picture
Post by: Lurch on December 20, 2012, 06:17:39 AM
Quote from: Kitch;719769
Anthony was in our back yard but at the moment he's down in Antarctica until November next year. I've already got a couple of repair's saved up for when he gets back.

Wow long wait :-) Glad I sent it to Amigakit, costs a bit more most likely but Chris is pretty good.

Also thinking about  getting the caps done as NovaCoder suggested, although they look okay to me but wouldn't hurt I guess. Have hinted about the screen/graphic tearing fix that 1d4 boards are meant to have but I haven't seen on mine.

Maybe this is a good thing after all :-)