Appalician son returns home over the holidays to his parents cabin. His dad asks him what he learned.
The boy replies Pi R Squared.
His mom turns to Pop and says "Pop we are wasting money. Everyone knows pie are round and cake are square."
The boy replies Pi R Squared.
His mom turns to Pop and says "Pop we are wasting money. Everyone knows pie are round and cake are square."
Gimp, if your gonna make fun of the hillbillies at least get the the labels right.
It’s Appalachian......dang Californians! 😉
It’s Appalachian......dang Californians! 😉
All electronic equipment can be placed into one of two categories:
- Items which need to be fixed.
- Items which will need to be fixed after you've poked around inside them!
I built up an amplifier pcb.
I didnt have a op amp for the DC servo so left it out.
The amp powered up ok but seemed to have low frequency oscillation.
I went round and round it checking all components but couldn't see why it oscillated.
I printed off circuit diagrams and poured over them for a while.
Then it hit me, the op amp missing provided a positive feedback path from output to input through a 1 meg resistor and a capacitor which were part of DC servo circuit.
So pinched an op amp from another pcb and it worked fine.
The op amp when in circuit inverts the signal.
Doh !
I didnt have a op amp for the DC servo so left it out.
The amp powered up ok but seemed to have low frequency oscillation.
I went round and round it checking all components but couldn't see why it oscillated.
I printed off circuit diagrams and poured over them for a while.
Then it hit me, the op amp missing provided a positive feedback path from output to input through a 1 meg resistor and a capacitor which were part of DC servo circuit.
So pinched an op amp from another pcb and it worked fine.
The op amp when in circuit inverts the signal.
Doh !
![IMG_1187[1].JPG](/community/data/attachments/730/730014-36a7bb423a590d743807430f240777c2.jpg?hash=Nqe7QjpZDX)
Technician's rules of conduct...
1) If it an't broke don't fix it.
2) If it is broke, know when to stop fixing it.
3) Never do anything you can't explain to your boss.
Typo Bob. Just because I was born in California does not mean I was raised there.😀
I blame it on the keyboard.
This is a link to an at least 18 years old manual for normal people who have to deal with engineers:
Engineers Explained
Engineers Explained
I relayed a true story in the write-up for the "Sadie's Monitor Stand" project at Audiodevelopers.com:
MPJA also carries some nice airtight strain reliefs for the AC cord–they call them “sealing glands”. I thought they were pretty cool and tried showing my wife my glands, but she just threatened to slap me when I asked her to take a look 🙂.
