I use my ears mostly for hum tracking & add eyes for bad filter cap detection (spuzz leaking out ends). Also bad filter caps will often heat up on their own when hi voltage is applied.
Parasitic oscillations? Monitor your amp's output while driving speakers. Driving load resistors may be quieter all right but speakers tend to bring out this misbehavior. And it is speakers you'll be driving after all so this is the best check. Nice to have a wave generator but even without one, use your guitar, pick low notes with tone controls down, and you may see chunks of "fuzz" riding on an otherwise clean-looking waveform. Your ears may detect a bit of distortion when you see these, if your amp has 'em.
Leo_Gnardo wrote:I use my ears mostly for hum tracking & add eyes for bad filter cap detection (spuzz leaking out ends). Also bad filter caps will often heat up on their own when hi voltage is applied.
Parasitic oscillations? Monitor your amp's output while driving speakers. Driving load resistors may be quieter all right but speakers tend to bring out this misbehavior. And it is speakers you'll be driving after all so this is the best check. Nice to have a wave generator but even without one, use your guitar, pick low notes with tone controls down, and you may see chunks of "fuzz" riding on an otherwise clean-looking waveform. Your ears may detect a bit of distortion when you see these, if your amp has 'em.
Next, what to do?
Thanks for the pro tips leo. I am building a waveform generator here at work - I know its not necessary, but smoke if you got em right?
"It's like what Lenin said... you look for the person who will benefit, and, uh, uh..."
beasleybodyshop wrote: I am building a waveform generator here at work - I know its not necessary, but smoke if you got em right?
And you're getting paid to do it . . . you lucky so & so. A signal generator and scope go together like ham & cheese so - on with the project. Sure beats plunk plunk plunkin' on a geetar string, but once all is said & done with the bench tests, you will be playing through any amp you build or fix for a final test.
Ross Perot Museum right? Remember our motto - "Let's look under the hood!"
beasleybodyshop wrote: I am building a waveform generator here at work - I know its not necessary, but smoke if you got em right?
And you're getting paid to do it . . . you lucky so & so. A signal generator and scope go together like ham & cheese so - on with the project. Sure beats plunk plunk plunkin' on a geetar string, but once all is said & done with the bench tests, you will be playing through any amp you build or fix for a final test.
Ross Perot Museum right? Remember our motto - "Let's look under the hood!"
Yeah it's called the Perot Museum of Nature and Science. Ross Perot is always showing up randomly, and will talk to anyone. lol. Once I was inside some exhibit casework fixing a broken spring hinge. I feel someone poking me in the back, turn around, and Ross Perot was like "Hey son! whatcha doin?" Funny guy.
Thanks for the links LABB. Great info in there!
"It's like what Lenin said... you look for the person who will benefit, and, uh, uh..."
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