aca620 board pic, comparisons needed

kipper2k · 13 April 2013, 00:40

Hi all,

I just received this new ACA620 today from Amiga kit and i noticed that the oscillator is crooked, when looking closer at the plcc chip it appears that it has been removed and reattached as the solder joints have excess solder on the pads. The pins on the plcc also have a brown tinge to it... is it just mine that shows this or does anyone else see this on theirs ? There also appears to be excessive grinding of the plcc chip that i'm sure generated a lot of heat. I haven't even plugged it in yet and i will wait for some other peoples comparisons before i do

Looking at the picture on Amigakit shows a nice looking one, it also has a TXC oscillator instead of the Koyo on mine ? Also looking at the edges of the oscillator shows dirt around the 4 sides and it is scratched

http://amigakit.leamancomputing.com/...oducts_id=1102

@Jens... can you comment on this please?

johnim · 13 April 2013, 01:16

this 1s the same

http://eab.abime.net/showpost.php?p=...postcount=2686

see post 2687 for mfilos answer

kipper2k · 13 April 2013, 01:17

here's another pic showing a pin with excessive solder. If the board was produced professionally i am sure we should not see this....

mfilos · 13 April 2013, 08:42

PIC being scratched is common with Jens products.
Indeed there is too much solder on the PIC showing like it's hand soldered.

Turran · 13 April 2013, 10:04

That looks like something I've soldered on 2 years ago. That is not a compliment =)

Loedown · 13 April 2013, 12:49

PIC can fail when it's reflowed like any other part, perhaps it failed and was replaced by hand?

Koyo is a Japanese manufacturer of oscillator blocks, TXC is either Chinese or Vietnamese going by their office locations. Does Koyo have a bad rep?

Crooked oscillator block does suggest a possible knock during manufacture.

I don't know why Jens would bother scratching off the top of the PIC in the first place, not that hard to guess which one it is based on ground / Vcc pins and a few I/O pins.

johnim · 13 April 2013, 14:47

mfilos said on other thread

It was sanded by default as Jens said to one of his posts. Was the same lot as the ones used in ACA1231 series where he wanted IC sanded to lower the IC's height, being able to mount a heatsink that would have problem attaching to this IC.

Loedown · 13 April 2013, 15:24

Quote:

Originally Posted by johnim

mfilos said on other thread

It was sanded by default as Jens said to one of his posts. Was the same lot as the ones used in ACA1231 series where he wanted IC sanded to lower the IC's height, being able to mount a heatsink that would have problem attaching to this IC.

A chip by default is reasonably flat, you use paste to take up the microscopic pits and bumps that the metal wouldn't contact by default. If that's been sanded flat to accommodate a heatsink then good sir I claim it to be a fraud because that isn't flat, hand sanded not machined.

mfilos · 13 April 2013, 16:58

Old years, hardware vendors used to sand the IC's for other competitors wouldn't know what IC they user on their hardware.

Kehil · 13 April 2013, 20:55

Quote:

Originally Posted by Loedown

A chip by default is reasonably flat, you use paste to take up the microscopic pits and bumps that the metal wouldn't contact by default. If that's been sanded flat to accommodate a heatsink then good sir I claim it to be a fraud because that isn't flat, hand sanded not machined.

As I understood, it was not sanded to be flatter, but to be lower. Just to fit under the heatsink.

Loedown · 14 April 2013, 02:07

Quote:

Originally Posted by mfilos

Old years, hardware vendors used to sand the IC's for other competitors wouldn't know what IC they user on their hardware.

Lacquer was another good method of stopping people from reworking.

Loedown · 14 April 2013, 02:09

Quote:

Originally Posted by Kehil

As I understood, it was not sanded to be flatter, but to be lower. Just to fit under the heatsink.

My mistake I took it to be that it was sanded back to allow a heatsink to be fitted to it. Although why wouldn't you just use a gull wing package to lower it?

Billy Miles · 14 April 2013, 09:16

Im no solder tech but my uncle was and that for sure is hand solder work!

Loedown · 15 April 2013, 05:59

Quote:

Originally Posted by Billy Miles

Im no solder tech but my uncle was and that for sure is hand solder work!

Hand soldering is still a valid form of manufacture if it's done properly. The part is a quad J leg , as long as the solder forms a good fillet on front of the leg and pad plus the same at the back it doesn't matter how it was soldered on. Granted a screen printer is always going to do a better job than the best hand solderer.

kipper2k · 15 April 2013, 06:15

There is no heatsink above the PLCC so i think it has been sanded to hide its identity. I am thinking that because these boards had problems with the firmware and were recalled, that the PLCC was pulled and replaced. The Oscillator may have been removed also to make it easier to resolder the replacement, only Jens can confirm i guess.

fitzsteve · 15 April 2013, 06:46

My original board was sanded before it went for the fix. Maybe the crystal is crooked to allow for a component on the motherboard?

mfilos · 15 April 2013, 09:12

They are sanded as Jens requested that in the past for the GALS to be sanded.
Dunno if the IC company still has old stock for Jens, or the request of his hasn't be changed yet.

majsta · 15 April 2013, 12:50

Oh my God what is this??? Even components are not positioned correctly... On my designs I take care of dimensions low as 0.001mm and here we all talking about 2 or more mm differences...
I don't believe that he soldered this because it is too unprofessional and looking at this I would never give so much money for it. Kipper2k i have some of your designs and it is much much better soldered than this. About sanding chips I don't see a point of doing that. What if you know what GAL is used it is not important because you don't have the code inserted in it. And those days you even don't need to know what chip is used attach logic analyzer on it and cache signals and replicate it. Maybe few hours of work...

demolition · 15 April 2013, 13:50

Quote:

Originally Posted by majsta

I don't believe that he soldered this because it is too unprofessional and looking at this I would never give so much money for it. Kipper2k i have some of your designs and it is much much better soldered than this. About sanding chips I don't see a point of doing that. What if you know what GAL is used it is not important because you don't have the code inserted in it. And those days you even don't need to know what chip is used attach logic analyzer on it and cache signals and replicate it. Maybe few hours of work...

Again, he's not trying to hide which chip he's using:

Quote:

Originally Posted by Schoenfeld

That sanded-down CPLD was my mistake: I ordered these parts from the same source as I did for the ACA1231, and I forgot to change the order to "don't sand down any more". They were sanded down on the ACA1231 in order to fit under a large cooler, which wasn't necessary in the end. I think it's obvious that there is no height problem on the ACA620, and to anyone with a little understanding of how an accelerator works, it's obvious that the CPLD in the data path is no secret (just a bidirectional driver with latch - you can type that faster than you can disassemble a jedec file).

Also, I think the soldering looks ok. It's not perfect and probably hand-soldered if it's a reworked board and I've seen worse looking factory rework on the A1200 motherboards.

Reynolds · 16 April 2013, 08:31

Quote:

Originally Posted by Loedown

Lacquer was another good method of stopping people from reworking.

Did you mean liqueur?

13 April 2013, 00:40	#1
kipper2k Registered User Join Date: Sep 2006 Location: Thunder Bay, Canada Posts: 4,323	aca620 board pic, comparisons needed Hi all, I just received this new ACA620 today from Amiga kit and i noticed that the oscillator is crooked, when looking closer at the plcc chip it appears that it has been removed and reattached as the solder joints have excess solder on the pads. The pins on the plcc also have a brown tinge to it... is it just mine that shows this or does anyone else see this on theirs ? There also appears to be excessive grinding of the plcc chip that i'm sure generated a lot of heat. I haven't even plugged it in yet and i will wait for some other peoples comparisons before i do Looking at the picture on Amigakit shows a nice looking one, it also has a TXC oscillator instead of the Koyo on mine ? Also looking at the edges of the oscillator shows dirt around the 4 sides and it is scratched http://amigakit.leamancomputing.com/...oducts_id=1102 @Jens... can you comment on this please? Last edited by kipper2k; 13 April 2013 at 01:04.

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13 April 2013, 01:16	#2
johnim Amibay Mod/Staff Join Date: Jun 2010 Location: birmingham uk Age: 48 Posts: 1,019	this 1s the same http://eab.abime.net/showpost.php?p=...postcount=2686 see post 2687 for mfilos answer

13 April 2013, 01:17	#3
kipper2k Registered User Join Date: Sep 2006 Location: Thunder Bay, Canada Posts: 4,323	here's another pic showing a pin with excessive solder. If the board was produced professionally i am sure we should not see this....

13 April 2013, 08:42	#4
mfilos Paranoid Amigoid Join Date: Mar 2008 Location: Athens/Greece Age: 45 Posts: 1,978	PIC being scratched is common with Jens products. Indeed there is too much solder on the PIC showing like it's hand soldered.

13 April 2013, 10:04	#5
Turran Moderator Join Date: May 2012 Location: Stockholm / Sweden Age: 49 Posts: 1,572	That looks like something I've soldered on 2 years ago. That is not a compliment =)

13 April 2013, 12:49	#6
Loedown Precious & fragile things Join Date: Feb 2009 Location: Victoria, Australia Posts: 1,946	PIC can fail when it's reflowed like any other part, perhaps it failed and was replaced by hand? Koyo is a Japanese manufacturer of oscillator blocks, TXC is either Chinese or Vietnamese going by their office locations. Does Koyo have a bad rep? Crooked oscillator block does suggest a possible knock during manufacture. I don't know why Jens would bother scratching off the top of the PIC in the first place, not that hard to guess which one it is based on ground / Vcc pins and a few I/O pins.

13 April 2013, 14:47	#7
johnim Amibay Mod/Staff Join Date: Jun 2010 Location: birmingham uk Age: 48 Posts: 1,019	mfilos said on other thread It was sanded by default as Jens said to one of his posts. Was the same lot as the ones used in ACA1231 series where he wanted IC sanded to lower the IC's height, being able to mount a heatsink that would have problem attaching to this IC.

13 April 2013, 16:58	#9
mfilos Paranoid Amigoid Join Date: Mar 2008 Location: Athens/Greece Age: 45 Posts: 1,978	Old years, hardware vendors used to sand the IC's for other competitors wouldn't know what IC they user on their hardware.

14 April 2013, 09:16	#13
Billy Miles AmiCDTV Join Date: Feb 2013 Location: Phoenix, USA Posts: 28	Im no solder tech but my uncle was and that for sure is hand solder work!

15 April 2013, 06:15	#15
kipper2k Registered User Join Date: Sep 2006 Location: Thunder Bay, Canada Posts: 4,323	There is no heatsink above the PLCC so i think it has been sanded to hide its identity. I am thinking that because these boards had problems with the firmware and were recalled, that the PLCC was pulled and replaced. The Oscillator may have been removed also to make it easier to resolder the replacement, only Jens can confirm i guess.

15 April 2013, 06:46	#16
fitzsteve Professional slacker! Join Date: Jul 2009 Location: Kent, UK Age: 44 Posts: 6,683	My original board was sanded before it went for the fix. Maybe the crystal is crooked to allow for a component on the motherboard?

15 April 2013, 09:12	#17
mfilos Paranoid Amigoid Join Date: Mar 2008 Location: Athens/Greece Age: 45 Posts: 1,978	They are sanded as Jens requested that in the past for the GALS to be sanded. Dunno if the IC company still has old stock for Jens, or the request of his hasn't be changed yet.

15 April 2013, 12:50	#18
majsta www.majsta.com Join Date: Jun 2010 Location: Banjaluka/Republic of Srpska Age: 43 Posts: 448	Oh my God what is this??? Even components are not positioned correctly... On my designs I take care of dimensions low as 0.001mm and here we all talking about 2 or more mm differences... I don't believe that he soldered this because it is too unprofessional and looking at this I would never give so much money for it. Kipper2k i have some of your designs and it is much much better soldered than this. About sanding chips I don't see a point of doing that. What if you know what GAL is used it is not important because you don't have the code inserted in it. And those days you even don't need to know what chip is used attach logic analyzer on it and cache signals and replicate it. Maybe few hours of work...

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