My 500+ Project

[djos]

Good to hear!

Indeed, just need to finish replacing the socket and plug her in when my new PSU shows up. *fingers Crossed*

[djos]

pics?

Will try and take some tonight, wife was giving me the hurry up.

[djos]

Awesome! Good to hear about the tracks after the clean up...  replacing sockets is a pain, make sure you do not make any solder bridges on the legs. Check with a magnifying glass if you have one.

Hope Gary works for you.

Az

Thanks, yeah removing a Socket is really hard, I wish I had a nice Weller Soldering/de-soldering station like back in my techo days as solder suckers are close to useless and de-soldering braid can be tricky to use on such small holes.

I do all this sort of work with a mag-glass mounted on my little small-pcb holding stand thingo.

[djos]

LOL, very nice - I mainly got the 68010 so that I can switch back to workbench from WHDLoad installed games.

Im going to order the latest Gen 68kIDE adaptor with CF module, 8MB Processor Ram module and 1MB Chip Ram board as soon as I've resurrected my 500+ - that'll give me 10MB Ram total and a 4GB CF HDD. :cool:

[djos]

Some goodies arrived in the mail today from AmigaKit:

Miggy PSU, cr2032 lithium battery kit, 2nd Comp Pro Joystick, RGB-SCART Cable, Miggy-VGA Adaptor

and my 68010 also arrived, just need to finish restoring my 500+ now (hopefully i'll get a chance tonight)!

[djos]

Managed to finish removing the corroded socket and install the replacement tonight but still have some work to do before my 500+ is fully working.

I reckon I need some finer grit sandpaper than I have to clean the feet on the Gary chip as I put it in and powered it up (just composite for now) and All I got was a flashing screen and an occasionally flashing Power Light (sort of dims to flash).

anyway here's some pics so far:

Lid on:
http://dl.dropbox.com/u/71121999/Amiga/2012-06-17%2018.18.32.jpg

Half the socket gone, board mostly cleaned:
http://dl.dropbox.com/u/71121999/Amiga/2012-06-20%2018.55.41.jpg

New Socket install (2x 24pin):
http://dl.dropbox.com/u/71121999/Amiga/2012-06-20%2020.55.19.jpg

Gary Chip in socket to make sure it fits + battery area and for a quick but so far unsuccessful test:
http://dl.dropbox.com/u/71121999/Amiga/2012-06-20%2020.57.44.jpg

One thing that does concern me is I popped a trace on the bottom of the mobo where it connects to a Gary socket pin and it pulled several centimetres off the board - I was able to solder it directly to the pin and gave it a coating of nail polish but am still unsure if that is enuf (time will tell i guess - might put up a pic tomorrow night).

I also tested all the socket pins with my multimeter to makes sure none of them where accidentally connected and got perfect results first time so happy with that.

If I cant fix this board I have discovered that getting hold of a Rev6a board is quite cheap from Europe and I should be able to transplant all the ECS chips and half the ram. :cool:

[djos]

Good idea, I'll try that.

Btw when looking at the pics can your trained eye see any pcb damage I need to repair?

[djos]

Btw, I quickly took some pics of my socket soldering work (bit amateur - been a long while & I miss having a proper desoldeing station) and the trace I had to repair:

http://dl.dropbox.com/u/71121999/Amiga/2012-06-21%2007.59.53.jpg
http://dl.dropbox.com/u/71121999/Amiga/2012-06-21%2007.58.45.jpg

[djos]

That lifted trace, you might want to see where it starts and solder a wire link from source to socket pin.

Insert Gary and see if the machine boots. The trace might look solid and connected along its length but more than likely there is a break in it.

Az

Good idea, thankfully I have some fine stiff wire lying around from a c64 reset switch mod. ATM I don't even get the insert disk screen likely due to the Gary chip feet needing more of a clean than I've given them.

[djos]

Hi Mate, where are you going to order the 68kIDE adaptor from? As these still available new? Or are you hoping to get one second hand?

MKL (aka mika) on amibay makes and sells the very latest version for about 50 Euros. :cool:

[djos]

So I took another crack at reviving my 500+ board last night:

I replaced the faulty trace with a direct wire connection:
http://dl.dropbox.com/u/71121999/Amiga/Photo%2021-06-12%207%2042%2033%20PM%20(HDR).jpg

I also tinned the feet of the Gary chip and tested a bunch of traces around the battery area with my multi-meter to ensure they weren't broken (none were) and then fired up my 500+.....

and got this: http://dl.dropbox.com/u/71121999/Amiga/Video%2021-06-12%208%2003%2052%20PM.mov

:cry:

It doesnt even attempt to boot from a floppy either so Im calling this mobo BUSTED! Oh well, it's been fun trying to repair it as I havent done any board level repair work sine about 1998!! gave me a good excuse to buy a new soldering iron too. :cool:

Anyway, all is not lost, I ordered a tested and working Rev6a Mobo from germany and will swap all the ECS chips onto it and upgrade the on board ram to 1MB using the chips from my Rev8a so it''l pretty much be a 500+ regradless.

[djos]

you made an 8 second video thats 20 megs?!?!

a 720p iPhone video will do that!

[djos]

LOL.. yeah that was a monster video

okies, I would swap the CIA chips...  and see if that gets any further into the boot process

from the cycling power light I would say Gary is faulty, a probable memory or bus conflict.

Before saying the mobo is dead, you really should swap other chips (other than agnus) and see if the board will boot, or gives the customary colours on boot. Better able to see the fault with the colour.

Az

Ok I'll swap the CIA chips and see what happens - at least the new mobo will give me a working Gary chip to test as well.

I also hooked up my miggy to my GBS-8220 via MiggyRGB-VGA adapter to GBS-8220 and I got a very distorted green screen that had rolling and tearing and the GBS-8220 couldnt lock onto it.

[djos]

@djos So you sourced a new a500+ board?

Not a Rev8a board, it's a Rev6a but I believe it can handle the ECS chipset without any mods and can take an extra 512k ram on-board basically making it a 500+ minus the battery backed RTC. :cool:

EDIT: my fatter Agnus may not work in the rev6a board tho but im happy if I get at least 1mb chip ram + 8mb CPU ram from tomthul.

[djos]

It's a shame you couldn't get the A500+ boardworking, would you consider sending it to AmigaManiac for repairs? He's in NSW and can repair most Amiga problems. I just think it's a shame that such a good motherboard would go to waste, I have a busted one here which I'm going to send to him too.

Im not aware of him? how much does he charge?

[djos]

Amiga Maniac has a web site here: http://www.amigamaniac.com/

I've bought a few items from him over the last couple of years, always been pretty good service, he's based in NSW.

He sells rom chips at a good price aswell.

Cheers, I sent him an email. :cool: