These components sure are a pain to remove. The caps are fine, but the 3 pin items are almost impossible to remove because of the old solder. I guess I need more flux. Anyway, interestingly my crystal is oscillating, but I've got no 5V at all - 12V is absolutely fine. Getting closer!
Part of the reason desoldering components is such a pain is no doubt that solder. 99.3% silver, 0.7% copper (if i read that correctly) definitely sounds like a pain in the ass. Sn60/Pb40 or Sn63/Pb37 and you'll wonder why soldering was ever a problem :P As for the component tester with the capacitors, if you use extensions to connect a cap to be tested (especially super skinny ones like those), i'd disregard any ESR readings as they're likely to be affected by all 4 connection points and the resistance of the thin wire itself. You'd be surprised how far off the numbers can be just from something like this. And it can get even worse when the wires turn out to not actually be copper, but copper-clad-aluminum or steel with even higher internal resistance (which I've had to deal with on croc leads as a nasty surprise) Just some food for thought.. not trying to argue that the caps aren't bad or anything, that's pretty much a given considering the age
A big part was indeed the solder. It is a bit problematic getting a hold of Sn60/Pb40 online here in the EU but fortunately my local mom-and-pop electronics store has it in stock. I later switched to leaded solder, mostly because that is what this board was manufactured with and it helped a great deal. Still, some parts or through holes are a pain to clean because of the large internal ground and power planes. I don't usually trust the ESR values from the component tester all that much but it is usually pretty good in pointing out completely dead capacitors. You're completely correct on the wires and connections affecting the measurement, I'm aware that has (or can have) a significant impact.
@@thowij If you couldn't get any, I would've offered to send a roll :P I kinda panic-bought a bunch of 250g spools of 63/37/3.5% flux when the whole RoHS bullshit first started cropping up. Also I kinda sorta went looking for a T1600 but it seems like you've gotten all the stock to be had in euroland or something :P The only one I could find was a T1600/40 in worse condition, with the seller obviously lying about how it "still worked recently" (with the rear corroded and the PSU jack completely green) and wanting 100+eur for it... meh
@@Knaeckebrotsaege Like any other computer labeled "vintage" they are way overpriced on ebay unfortunately. Some people think "rare" or "vintage" equals "valuable" but it just doesn't work like that. Even for a somewhat rare machine 100+ is just too much. I realistically wouldn't pay more than 60 eur for a non-working machine.
Dear Thom, I have a similar problem with my newly purchased T1600 as you had. The last owner has tried to repair the power supply module, and replaced some capacitor. Now the C2 is missing :( Can you tell me, what value the C2 has?
It's in the schematic on my GitHub (linked in the description ;)) C2 is a 10V 1800uF electrolytic capacitor, should be identical to C1 both in size and value. This is all assuming your PSU board is revision FIVPS2.
@@thowij many thank! My PSU board is a FIVPS3 version, and on this board is the C1 a 10V 3300uF electrolytic capacitor, but I assume then the C2 must be a 10V 3300uF on the FIVPS3 revision.
@@gaborsafrany7682 To be honest I would'nt make such assumptions. There are some not insignificant differences between the revisions, including component value, count and designation. As they say: Assumption is the mother of all f-ups. Edit: I just remembered I received some pictures of a FIVPS3 board from another viewer. C1 and C2 should be the 2 large caps near the barrel jack. If they are I think it's safe to assume they should be the same value.
@@thowij yes, C1 and C2 are the 2 large capacitors near the barrel jack, that's the reason, I assumed, they must to have the same values.Secondly on your FIVPS2 are the C1 the same 10V as on the FIVPS3, the difference is "only" the uF. By the way, I like your work, and video, great work! Thanks again for your reply and "thinking on the solution together"
@@gaborsafrany7682 In that case it is safe to assume. I'm always cautious making assumptions, more often than not they make things worse. Thank you for your kind words and good luck with the repair!
These components sure are a pain to remove. The caps are fine, but the 3 pin items are almost impossible to remove because of the old solder. I guess I need more flux.
Anyway, interestingly my crystal is oscillating, but I've got no 5V at all - 12V is absolutely fine. Getting closer!
Nice job with the dremel :D
Part of the reason desoldering components is such a pain is no doubt that solder. 99.3% silver, 0.7% copper (if i read that correctly) definitely sounds like a pain in the ass. Sn60/Pb40 or Sn63/Pb37 and you'll wonder why soldering was ever a problem :P
As for the component tester with the capacitors, if you use extensions to connect a cap to be tested (especially super skinny ones like those), i'd disregard any ESR readings as they're likely to be affected by all 4 connection points and the resistance of the thin wire itself. You'd be surprised how far off the numbers can be just from something like this. And it can get even worse when the wires turn out to not actually be copper, but copper-clad-aluminum or steel with even higher internal resistance (which I've had to deal with on croc leads as a nasty surprise)
Just some food for thought.. not trying to argue that the caps aren't bad or anything, that's pretty much a given considering the age
A big part was indeed the solder. It is a bit problematic getting a hold of Sn60/Pb40 online here in the EU but fortunately my local mom-and-pop electronics store has it in stock. I later switched to leaded solder, mostly because that is what this board was manufactured with and it helped a great deal.
Still, some parts or through holes are a pain to clean because of the large internal ground and power planes.
I don't usually trust the ESR values from the component tester all that much but it is usually pretty good in pointing out completely dead capacitors.
You're completely correct on the wires and connections affecting the measurement, I'm aware that has (or can have) a significant impact.
@@thowij If you couldn't get any, I would've offered to send a roll :P I kinda panic-bought a bunch of 250g spools of 63/37/3.5% flux when the whole RoHS bullshit first started cropping up.
Also I kinda sorta went looking for a T1600 but it seems like you've gotten all the stock to be had in euroland or something :P The only one I could find was a T1600/40 in worse condition, with the seller obviously lying about how it "still worked recently" (with the rear corroded and the PSU jack completely green) and wanting 100+eur for it... meh
@@Knaeckebrotsaege Like any other computer labeled "vintage" they are way overpriced on ebay unfortunately. Some people think "rare" or "vintage" equals "valuable" but it just doesn't work like that. Even for a somewhat rare machine 100+ is just too much. I realistically wouldn't pay more than 60 eur for a non-working machine.
sandblast the i/o shield or sand it
Dear Thom,
I have a similar problem with my newly purchased T1600 as you had. The last owner has tried to repair the power supply module, and replaced some capacitor. Now the C2 is missing :( Can you tell me, what value the C2 has?
It's in the schematic on my GitHub (linked in the description ;))
C2 is a 10V 1800uF electrolytic capacitor, should be identical to C1 both in size and value.
This is all assuming your PSU board is revision FIVPS2.
@@thowij many thank! My PSU board is a FIVPS3 version, and on this board is the C1 a 10V 3300uF electrolytic capacitor, but I assume then the C2 must be a 10V 3300uF on the FIVPS3 revision.
@@gaborsafrany7682 To be honest I would'nt make such assumptions.
There are some not insignificant differences between the revisions, including component value, count and designation.
As they say: Assumption is the mother of all f-ups.
Edit: I just remembered I received some pictures of a FIVPS3 board from another viewer. C1 and C2 should be the 2 large caps near the barrel jack. If they are I think it's safe to assume they should be the same value.
@@thowij yes, C1 and C2 are the 2 large capacitors near the barrel jack, that's the reason, I assumed, they must to have the same values.Secondly on your FIVPS2 are the C1 the same 10V as on the FIVPS3, the difference is "only" the uF.
By the way, I like your work, and video, great work!
Thanks again for your reply and "thinking on the solution together"
@@gaborsafrany7682 In that case it is safe to assume. I'm always cautious making assumptions, more often than not they make things worse.
Thank you for your kind words and good luck with the repair!