On 8/2/2019 5:46 PM, Scott Dorsey wrote:
John Williamson wrote:
Please check Phil Allison's previous posting record. He has a habit of
accusing others of suffering from his own shortcomings. While he has a
reasonable knowledge of certain aspects of the audio business, he shows,
when posting, personality problems which vary in seriousness for no
apparent reason. He is banned from many usenet and other social media
groups for this reason.
This is true.
Now, he does have a good point that the original poster likely doesn't
have the right equipment or skills to diagnose the problem. But....
everybody has to start somewhere and if you don't try you'll never learn.
I've got a Tektronix 465M o'scope, a digital multimeter, and an ESR
meter.
What more do you need?
And having been a microwave/Radio frequency engineer for nearly 3
decades, I'm not likely to electrocute myself on the bench!
But I'll admit I don't trouble-shoot modern switching power supplies
very often. But it can't be denied that these are NOT trivial circuits
to diagnose, especially WITHOUT a proper schematic!
And even your article mentions the when-in-doubt-replace-it, brute
force approach to repairing these tough-dog problems. I've certainly
successfully done this in the past, but I'm not sure I wanna do that
on this unit, because my stock of spare parts is not what it used to
be.
:/
This unit might end up on Ebay.....
Haha!
He is also resident in the kill files of many posters here, and posters
responding to him as you have also end up in the kill files, so do not
get the hep they would like.
He posts interesting and accurate stuff often enough that I am reluctant to
killfile him, although he will go on these weird rants occasionally.
With proper precautions, working on SMPS units is perfectly safe. I hate
doing it, because I dislike working on SMDs as my eyesight is not what
is used to be.
Two things changed my mind about this: the Optivisor magnifier (accept no
cheap Asian substitutes!) and the hot tweezers. The tweezers allow you to
pick up an smt resistor, put it aside, then put it back as needed. It makes
working on smt discretes much much easier. I had no idea how wonderful
either one of these things was until I tried them.
--scott