It could have been so good ... - Page 2

8bitbubsy · 28 September 2009, 13:09

Another way is to twist the capacitors (if you're SURE you have the replacement parts) so they break off, then take off the little black plastic socket, then desolder the remaining pins. Then it's easy to solder on the new ones! If you want to to an even better job, make sure you remove the old solder with a solder wool, add flux, then add some new and dilicious solder on the pads.

Good luck, I'm actually going to recap my A1200 mobo now, as we speak. First time!

Thorham · 28 September 2009, 16:46

Quote:

Originally Posted by 8bitbubsy

Another way is to twist the capacitors (if you're SURE you have the replacement parts) so they break off

Now that's some bad advice

Do not twist any parts off, ever, or you'll risk damaging the circuit board

Always desolder the parts you want to remove, even if it takes more time

8bitbubsy · 28 September 2009, 17:34

Quote:

Originally Posted by Thorham

Now that's some bad advice

Do not twist any parts off, ever, or you'll risk damaging the circuit board

Always desolder the parts you want to remove, even if it takes more time

Not easy if you don't have two soldering irons. I bent/twisted all of the SMD caps now, they all went off fine. Desoldered the remaining pins too.

DoogUK · 28 September 2009, 18:31

Fortunately the little black sockets protect the board, otherwise you WOULD risk tearing tracks up off the PCB surface.

06 October 2009, 02:46

Thanks for all the advice guys, at the moment I am waiting for an ATX cable to arrive and I will see if that will fix the problem with the sound, I have a feeling that perhaps the PSU is weak and then using a step up transformer is not powerful enough. Will let you guys know what happens with the new ATX cable.

25 October 2009, 03:48

Right well I finally got the ATX PSU hooked up and powered up the miggy but the sound is still crappy, really low and fuzzy sounding. So I guess I need to replace the CAPS but to be honest I dont trust myself with an iron, is anyone interested in selling me their a1200 motherboard or who can change the caps?

coze · 25 October 2009, 04:03

if you cover the shipping I can change them for you.

25 October 2009, 04:12

that would be great mate, when would be a good time for you?

coze · 25 October 2009, 04:25

you've been pm'ed !

FOL · 25 October 2009, 11:34

Quote:

Originally Posted by Thorham

Now that's some bad advice

Do not twist any parts off, ever, or you'll risk damaging the circuit board

Always desolder the parts you want to remove, even if it takes more time

Not true, if you debraid the contacts first. If you dont debraid then yes, I would agree and say its bad advice.

FOL · 25 October 2009, 11:36

Quote:

Originally Posted by ami_junkie

Right well I finally got the ATX PSU hooked up and powered up the miggy but the sound is still crappy, really low and fuzzy sounding. So I guess I need to replace the CAPS but to be honest I dont trust myself with an iron, is anyone interested in selling me their a1200 motherboard or who can change the caps?

Cap leakage could have also damaged the sound circuit, I have seen a few boards with this problem and the preamp has been damaged. So changing the caps had no effect.

AlfaRomeo · 25 October 2009, 13:29

Quote:

Originally Posted by FOL

Not true, if you debraid the contacts first.

What that means??

AlfaRomeo · 25 October 2009, 13:45

Quote:

Originally Posted by FOL

Cap leakage could have also damaged the sound circuit, I have seen a few boards with this problem and the preamp has been damaged. So changing the caps had no effect.

After clean the mobo I changed all my A600 caps but it still as beginning, when power on the power led still flashing strongle/weak and my monitor doesn´t have image seems that the A600 doesn´t have composite out and my tv doesn´t detect the A600 RF. The CapsLock key seems work ok, when I press it still with the led on until next reboot..
Could the acid damaged some circuits??

FOL · 25 October 2009, 13:47

Quote:

Originally Posted by AlfaRomeo

What that means??

Its a tool if you like, you heat the braid against the solder with the iron. The braid then sucks / mops up the solder. Basically it removes the solder from the component legs.

Quote:

Originally Posted by AlfaRomeo

After clean the mobo I changed all my A600 caps but it still as beginning, when power on the power led still flashing strongle/weak and my monitor doesn´t have image seems that the A600 doesn´t have composite out and my tv doesn´t detect the A600 RF. The CapsLock key seems work ok, when I press it still with the led on until next reboot..
Could the acid damage some circuits??

Yes, cap leakage can eat the tracks of the circuit away, over time.

Not 100% sure about what your saying.
Do you mean the A600 has always been faulty?

By your pictures a few ic's have their legs messed up by cap damage, hence the green around the legs. Also there appears to be alot of track damage.
If the ic's arent damaged then it will be the holes between the top and bottom of the board that have corroded.
Best way to tackle the holes, is to the scrape the green / black stuff off them, to reveil the copper. Then put a thin piece of wire through the hole and solder it. Doing this should repair the connection, between the top and bottom layers (aslong as the board is double sided, if its multi-layered, then your going to have problems).

AlfaRomeo · 25 October 2009, 14:19

Quote:

Originally Posted by FOL

Not 100% sure about what your saying.
Do you mean the A600 has always been faulty?

..aslong as the board is double sided, if its multi-layered, then your going to have problems.

Thanks by your explanation FOL
Not always, it worked but was stored many years and when I unpacked and test it doesn´t works any more and when opened the case it was like the photos describes.

There are boards with 2 layers and others with more than 2 for the A600 and A1200?

AlfaRomeo · 25 October 2009, 14:30

Quote:

Originally Posted by rkauer

Pending in your abilities with a soldering iron, not a very hard job.

If you have two soldering irons just heat the two legs of the capacitor and it will sack out the board quite nicely.

How do you grab two irons at same time and still desolder with the precision that is needed in this case?
I think if I try to desolder the SMD caps legs with 2 irons I will broke something

FOL · 25 October 2009, 15:14

Quote:

Originally Posted by AlfaRomeo

How do you grab two irons at same time and still desolder with the precision that is needed in this case?
I think if I try to desolder the SMD caps legs with 2 irons I will broke something

Its possible, if you have good soldering abilities as Rkauer put it.

Quote:

Originally Posted by AlfaRomeo

Thanks by your explanation FOL
Not always, it worked but was stored many years and when I unpacked and test it doesn´t works any more and when opened the case it was like the photos describes.

There are boards with 2 layers and others with more than 2 for the A600 and A1200?

Im not sure with A1200 or A600 boards, havent really had to go that deep into to find out wether or not they are multi-layered. I just know from past experience of working on other electrical devices. The Amiga, may have been just before multi-layer came out. Maybe someone else could give a dafinitive answer.

I know the Index Access is definately multi-layered, atleast the 1's I worked on were.

AlfaRomeo · 30 October 2009, 16:35

Quote:

Originally Posted by rkauer

If you have two soldering irons just heat the two legs of the capacitor and it will sack out the board quite nicely.

I have tried this technic and it works great to take out smd caps from mobo

For anyone who don´t want to spend too much money in soldering equipment it´s the best bet.

@ rkauer
Great technic

06 November 2009, 06:00

I met with Coze yesterday and handed him the A1200, what a nice bloke! It is so rare to meet other Amiga users in Japan and it is great to see how nice they are. Anyways my A1200 is now is his capable hands ... and he managed to fix it! I here by crown Coze as the Amiga Don of Japan!

chiark · 06 November 2009, 08:49

Quote:

Originally Posted by ami_junkie

I met with Coze yesterday and handed him the A1200, what a nice bloke! It is so rare to meet other Amiga users in Japan and it is great to see how nice they are. Anyways my A1200 is now is his capable hands ... and he managed to fix it! I here by crown Coze as the Amiga Don of Japan!

Tip top stuff

It's rare to meet fellow Amigans in the UK, so I imagine in Japan it's almost impossible!

I send virtual hugs to Coze for being a true forum hero

And now, before Z says it... Pics?

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Need some good help here...	xalalalala	support.Hardware	4	11 November 2011 21:55
Is this any good?	chrispy	Hardware mods	23	10 September 2010 18:14
2000 - black screen... Chips good... PSU good...	chiark	support.Hardware	45	09 January 2009 05:41
Is this any good?	ORSM T	New to Emulation or Amiga scene	3	30 June 2007 18:22

28 September 2009, 13:09	#21
8bitbubsy Registered User Join Date: Sep 2009 Location: Norway Posts: 1,718	Another way is to twist the capacitors (if you're SURE you have the replacement parts) so they break off, then take off the little black plastic socket, then desolder the remaining pins. Then it's easy to solder on the new ones! If you want to to an even better job, make sure you remove the old solder with a solder wool, add flux, then add some new and dilicious solder on the pads. Good luck, I'm actually going to recap my A1200 mobo now, as we speak. First time!

28 September 2009, 18:31	#24
DoogUK Doogster Join Date: Dec 2007 Location: Dorset Posts: 1,069	Fortunately the little black sockets protect the board, otherwise you WOULD risk tearing tracks up off the PCB surface.

06 October 2009, 02:46	#25
ami_junkie Posts: n/a	Thanks for all the advice guys, at the moment I am waiting for an ATX cable to arrive and I will see if that will fix the problem with the sound, I have a feeling that perhaps the PSU is weak and then using a step up transformer is not powerful enough. Will let you guys know what happens with the new ATX cable.

25 October 2009, 03:48	#26
ami_junkie Posts: n/a	Right well I finally got the ATX PSU hooked up and powered up the miggy but the sound is still crappy, really low and fuzzy sounding. So I guess I need to replace the CAPS but to be honest I dont trust myself with an iron, is anyone interested in selling me their a1200 motherboard or who can change the caps?

25 October 2009, 04:03	#27
coze hastala vista winny vista Join Date: Feb 2006 Location: mt fuji Age: 46 Posts: 1,335	if you cover the shipping I can change them for you.

25 October 2009, 04:12	#28
ami_junkie Posts: n/a	that would be great mate, when would be a good time for you?

25 October 2009, 04:25	#29
coze hastala vista winny vista Join Date: Feb 2006 Location: mt fuji Age: 46 Posts: 1,335	you've been pm'ed !

06 November 2009, 06:00	#39
ami_junkie Posts: n/a	I met with Coze yesterday and handed him the A1200, what a nice bloke! It is so rare to meet other Amiga users in Japan and it is great to see how nice they are. Anyways my A1200 is now is his capable hands ... and he managed to fix it! I here by crown Coze as the Amiga Don of Japan!

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