I am about to recap and replace two I/C power regulators in a phono pre amp.
If you have any good do's & don'ts... I'm all ears.
Do the I/C's need any particular attention in handling?
I will use nose pliers to act as a heat shrink on the connectors, and a low wattage iron (15w) other than that, anything else I should know about?
Thanks, and have a nice weekend.
If you have any good do's & don'ts... I'm all ears.
Do the I/C's need any particular attention in handling?
I will use nose pliers to act as a heat shrink on the connectors, and a low wattage iron (15w) other than that, anything else I should know about?
Thanks, and have a nice weekend.
Heatsinks were needed when soldering germanium semiconductors. Usually not for silicon; in fact they could make things worse by taking heat away so you need to leave your iron in contact for longer. Quick good soldering is the key; this may need more than 15W.
I echo Bill's question.
I echo Bill's question.
No special handling requirements for any of the parts and no real need for a heat shunt. The solder should 'take' instantly. I usually mentally count as I apply heat (50watt iron and large tip... bigger can be better sometimes as it transfers sufficient heat pretty much instantly). Three, two, one as I apply the cored solder to each joint. Job done.
I take it this is the one with the 7815/7915 regs 🙂
I take it this is the one with the 7815/7915 regs 🙂
thanks for the tips, I am replacing the two i/c's because they are 47p each and they are right next to the caps. The phono has run 24/7 for six years or more, so while I am at it, it's a job done.
https://goo.gl/photos/LacLuNnrp635Jm5m9
https://goo.gl/photos/LacLuNnrp635Jm5m9
indeed it is, new Panasonic caps and two I/C's arrived from CPC this morning. £1.62 for the 2 large caps, 90p for 10 smaller caps, 84p for two regs
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hi Mike50,
I am replacing the two i/c's,well I would put a meter for voltage and one finger on them for heat test and see how there doing ,You can replace them if you just won't too,but if not broke don't need fixing,beside you screw up a trace or a hole in the board,,,*&^(^%$SH..
Best to ya!
NS
I am replacing the two i/c's,well I would put a meter for voltage and one finger on them for heat test and see how there doing ,You can replace them if you just won't too,but if not broke don't need fixing,beside you screw up a trace or a hole in the board,,,*&^(^%$SH..
Best to ya!
NS
I should be ok, I've been soldering things since around 1969, but thanks for the tip
Hi mike50,🙂
Great now your a pro !,Here's your data sheet as the rest of that reg circuit is cheap and caps do fail,life ex 5 years plus now you can upgrade or replace all of them in that circuit then you'll have a new reg circuit ! instead of a patched up one,lol.😀
I like the dc volt meter if it's close it's close enough,lol. and of course the finger sazs it just warm is ok too!
Happy Listening !
NS
Great now your a pro !,Here's your data sheet as the rest of that reg circuit is cheap and caps do fail,life ex 5 years plus now you can upgrade or replace all of them in that circuit then you'll have a new reg circuit ! instead of a patched up one,lol.😀
I like the dc volt meter if it's close it's close enough,lol. and of course the finger sazs it just warm is ok too!
Happy Listening !
NS
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it's just a shame I didn't have the foresight to buy some de solder braid while I was at it, so my friday project will have to wait...........
It's impossible to re cap without it...... ******
It's impossible to re cap without it...... ******
and we're back in business, I found an old copper woven screened canford audio mic cable, the braid in that will do nicely
job done, sinatra pounding out of my speakers, not a buzz to be heard. thanks audiodiy, I couldn't have done it without you
a job well done.on further inspection C46 was fried to a crisp inside. I didn't do the i/c's after all. Like the man said, if it ain't broke......
At least I have them in stock with a few more caps, for the future......
I laugh in the face of earth loops, I knew it was a mains buzz.......
At least I have them in stock with a few more caps, for the future......
I laugh in the face of earth loops, I knew it was a mains buzz.......
Hey mike50,
That's great NOW enjoy !
I use my eyes to test for bad caps,most of the time they are puffed up on top, leaning to one side ,rubber plug in between the leads is bulging,of of course heat discolor ,then I remove them and test them,most VOM's now have a cap testor but if you want the best buy one that tests capacitance,ESR ,I have a sencore and used it for years,it has a chart that shows the ESR and you can cross check this with a good know value to see if that cap you tested is approaching EOL(end of life) and should be replaced,also if you leave it powered up all the time ,you don't have as much voltage ,temp or other varibles inside the cap so it basically stays equal inside.
Have fun I do!
NS
That's great NOW enjoy !
I use my eyes to test for bad caps,most of the time they are puffed up on top, leaning to one side ,rubber plug in between the leads is bulging,of of course heat discolor ,then I remove them and test them,most VOM's now have a cap testor but if you want the best buy one that tests capacitance,ESR ,I have a sencore and used it for years,it has a chart that shows the ESR and you can cross check this with a good know value to see if that cap you tested is approaching EOL(end of life) and should be replaced,also if you leave it powered up all the time ,you don't have as much voltage ,temp or other varibles inside the cap so it basically stays equal inside.
Have fun I do!
NS
Hi Mike,🙂
If possible you can turn your pcb upside down and heat the joint with your soldering iron and gravity will wick the solder off the pcb pad and on to your iron tip,solder removed.....also will fix bridged pads ,the solder bridge will separate and you'll have 2 pads again,That TIP came from heath kit!
NS😀
Electrolytics will age and need replacing.
Semiconductors rarely need replacing unless they have been over stressed or attacked with static discharge.
Semiconductors rarely need replacing unless they have been over stressed or attacked with static discharge.
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