Terrible electronic jokes

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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 !
 
R.I.P.
 

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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 :).​
 
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