HELP!...with an lfo!!!!!.....

[deadastronaut]

right ive built this lfo as part of a circuit onto pcb...twice!..and both times it just wont flash the led.

it all works fine on the breadboard..nice slow and fast pulsing...but as soon as i put it on pcb it wont have it...

heres the schematic....which works fine!..


and heres the pcb layout lfo part...( i isolated all the relevant lfo parts..)



heres my numbers for the op amp..tlo72.

p1  8.46 - 133  up n down...
p2  5.72 - 3.59 up n down..
p3  5.84 - 3.47  up n down
p4    0.00
p5  5.44 - 3.90  up n down
p6  5.44 - 3.90  up n down
p7  5.44- 390   up n down
p8  9.09......

so its definately oscillating on the ic, just not doing it with the leds....can anyone spot an error in the pcb conversion...i'm losing it with this @#$%ing  lfo!...

thanks in advance for any help...rob.  (speed pot is 470kb. btw...)

[deadastronaut]

whooohooo......got it working....nice n quiet too.....


i had an end of another bloody resistor touching another...   @#$%er...

[newfish]

...so you're building another Trem then?   

[deadastronaut]

nope!...

this..verified today...whooo hooo....

http://www.diystompboxes.com/smfforum/index.php?topic=88582.msg792803#msg792803


but yeah its a much better lfo....noiseless...

[newfish]

WOW!

That's insane!

Congratulations - here's your straightjacket... 

[deadastronaut]

^ ha ha, yeah i need one now!!!....