Recent content by gphil5

Thank everyone for the input... I'll be implementing a lot of the suggestions. I appreciate the input! The only reason I used such small resistors was because of my on-hand capacitor selection. Ordering smaller ones as suggested... This oscillator is being used to switch an IR LED...

AlephZero... Using labels in the above link: R1=R4=470 R2=R3=1.8k C1=C2=0.01uF Q1=Q1=2N3904 I understand I'll need some trim pots to fine tune, but was just wanting to get the basics working before proceeding. I don't completely follow the R2/R1 relationship compared to Hfe. R1=150 - 470...

NascentOxygen, I've used both both a decent lab supply, and a cheap ebay one... same thing. However, I hooked it up to a 9V battery after your response... no drift. Since this will be ultimately powered by battery, I guess the issue is resolved. However... can you explain more about how a...

Hello all, I've breadboarded a simple astable multivibrator to generate 38kHz (identical to http://upload.wikimedia.org/wikipedia/commons/6/6a/Transistor_Multivibrator.svg) using 2N3904s. Upon power up, it's a solid 38Khz. After 60 seconds, it's drifted up to ~44Khz... and stabilizes to...