I hate when the power supply rail seems shorted to ground. Often there are multiple components that may be the reason for a short to ground. Which one to disconnect first? I know that instruments exist that can detect where fault currents are running but they are expensive. I know of no simple trick to approach such fault-finding.
Perhaps increase the short-circuit current and try with an infrared camera.
Perhaps increase the short-circuit current and try with an infrared camera.
Hard shorts are usually not that hard to find. Its the one or two ohm shorts that make me just crank up the power until something smokes, or the backwards cap shoots its goo.
Cheap ohm meters are worthless for short finding since the test leads often have more resistance than the short, so...
Force a current through the short using a power supply set to a low enough voltage and proper polarity so that nothing will be damaged if the short suddenly clears. The magnitude of this current should be high enough to generate a measurable voltage, but not big enough to melt wiring or blast traces off a board.
Then take the cheap voltmeter (or a good one if so equipped) and go looking for the lowest voltage point on the shorted rail. You can usually leave the ground probe at the power source (usually the filter cap or input to the PC board) but if hunting for a stubborn short inside a multi-layer PCB, sometimes you need to walk both probes up and down the shorted path.
DIY things I hate...
1. The virtual dissapearance of surplus stores.Getting hard to find any.
2. The general attitude by everybody that because you understand electronics that you should willingly repair all their broke stuff for free, just because you understand and like such things. (Starting back in the sixties with car stereos, CBs and TVs, which I insisted I knew nothing about, because everybody had one that was broke!)
3. The increasing perception that the ability to connect Arduinos and sub assemblies and program them to blink an LED constitutes an understanding of electronics.
4. Letting the smoke out of ALL transistors of one channel of an amp from bumping and breaking off the bias adust pot on a differential amp and pulling both sides go the supply rails.
I have others, but that's a start.
Doc
1. The virtual dissapearance of surplus stores.Getting hard to find any.
2. The general attitude by everybody that because you understand electronics that you should willingly repair all their broke stuff for free, just because you understand and like such things. (Starting back in the sixties with car stereos, CBs and TVs, which I insisted I knew nothing about, because everybody had one that was broke!)
3. The increasing perception that the ability to connect Arduinos and sub assemblies and program them to blink an LED constitutes an understanding of electronics.
4. Letting the smoke out of ALL transistors of one channel of an amp from bumping and breaking off the bias adust pot on a differential amp and pulling both sides go the supply rails.
I have others, but that's a start.
Doc
What I hate about DIY audio
1) finding a suitable case 4 the circuits
1a) Drilling out the case and stuffing the case
2) SMT that was not mounted on boards ( I'm going blind and have fat fingers)
3) making decisions on caps, resistors and wires? ( ie. Does this cap sound better, etc)
4) some circuits and projects without much support ( not sure by looking at a circuit what it does, just hope it works when I put it together)
5) being able to distinguish if one circuit sounds better than the other. (Lol)
1) finding a suitable case 4 the circuits
1a) Drilling out the case and stuffing the case
2) SMT that was not mounted on boards ( I'm going blind and have fat fingers)
3) making decisions on caps, resistors and wires? ( ie. Does this cap sound better, etc)
4) some circuits and projects without much support ( not sure by looking at a circuit what it does, just hope it works when I put it together)
5) being able to distinguish if one circuit sounds better than the other. (Lol)
Finally, after 5 years, finding time to put together my WE300B monoblocks, enjoying 2 glorious weeks of listening them one of them goes tits up with a kaput power transformer - situation compounded by the issue that the bloke who made the transformers for me died 2 years ago.
Attachments
Making the enclosures for the speakers. Took me more than 90% of the time and it was the least fun part. I guess it's the dirty work but somebody (me) has to do. I usually have lots of ideas and I got all the parts ready but the part of making the enclosures are what stopping all these projects. Fine tuning and xover designs are like piece of cake for me.
I really hate looking for the right and final scheme. I'm dummy with schemes, so I have to rely on experts here. Sadly, often mistakes appear, eg wrong diode polarity which author will fix in new version and it will appear in post eg #547...
But I have to say I love soldering. Even my last Toshiba tubes/transistor had nice spark which turned into fire. OR: Rectifier diodes nicely exploded. It was exciting too
But I have to say I love soldering. Even my last Toshiba tubes/transistor had nice spark which turned into fire. OR: Rectifier diodes nicely exploded. It was exciting too
1) Aiming to buy quality components only to find no stock or worse 10:+ qty only allowed from supplier.
2) courier cost to my country is insane.
