I need some schooling please.
Ic5 on the lowrider is a LM324. My voltages at pin 8 and pin 14 are whack.
Pin 8=-5.4mv
Pin 14=1.19 v
according to the build doc they should be:
pin 8=2.2 mv
Pin 14=7.9 v
What I don't understand,(and my knowledge is limited on pretty much everything) is that according to the pinouts pin 9 and 10 feed pin 8, and pin 12 and 13 feed pin 14.
Is if my voltages are correct at 9 and 10 as well as 12 and 13, how can the chip be feeding me the wrong voltages?
Or am I completely off the mark?
Thanks for your help.
I tested 5 chips all with the same result, so unless I got a bad batch of chips from Tayda, I am doing something else wrong somewhere.
I ordered a new batch of lm324s from digikey to try. I also might throw in a tl074 while I wait just for giggles.
Whelp, wasn't the lm324's. Same result as the Tayda chips.
Time to start diagnosing the rest of the circuit. Yay me.
I will post pics and voltages tonight.
I have verified all resistors and capacitors.
All Diodes and electrolytics are in the correct orientation.
I have replaced all IC's and transistors.
After having built about 20 Madbean boards with success, this one is truly a kick in the face.
Pics and voltages as promised. I am giving it until Friday before I throw in the towel..(https://uploads.tapatalk-cdn.com/20181001/303b680596ca7a851ffa5577b4883dc9.jpg)(https://uploads.tapatalk-cdn.com/20181001/7d674cec1248dffbfe253120f7746163.jpg)(https://uploads.tapatalk-cdn.com/20181001/b8b5dbbeb0874daff5ac979c60088abf.jpg)
Sent from my SM-G960U using Tapatalk
File this one under:
Chuck it in the F*ckit Bucket.
Whelp, I am too damn stubborn to give up on anything....
After dicking with it for a few hours yesterday and about 3 today, turns out it was a bad socket for the LM324. Voltages are where they need to be everywhere except ic7, but I think I fried that chip so I ordered new ones.
Has anyone encountered bad sockets? Seems like it should be foolproof.
Thanks for following.
I have and it was a bugger to troubleshoot (as you now know). I really should have caught it going in because it was a discolored 14 pin. I never really figured out what the problem was because even with corrosion the metal on metal should self clean those things. Still, replaced it, put the IC back in and it worked. I tossed it without doing a post mortem.