More 555

[Slava]

if  R is connected between 8(+Vcc) and 6,  and C  is connected between 6 and
1(GND)
then T=1.4 x R x C  (with 50% duty cycle).

f=1 / T

3 - out
from 5 to GND another C
6 is connected to 2
between 7 and 6 is  resistor 1/2 x R
4 and 8 are +Vcc

What freq do you need?

Slava.


>      I built Bruce Bowlings's 555 injector cleaner and I'm having a bit
>of trouble with it. To start, I built it (I thought) just as perscribed.
>No Go. I started playing with different resistances, specificly the
>charge/discharge resistors. I found thant *no* resistance in either
>position gives me the highest frequency (sounds reasonable right?) I
>then measure the frequency at only 120hz...WAY off target .BTW, the
>injector sounds like its only running reasonably fast, confirming this
>measurement. I have scince started substituting larger caps (to get a
>feel for the chip). The original recipie called for a 470pf. I have
>tried all the way up to 8mf with NO change. What gives? I'm no EE so
>give it to me in laymans terms :)
>
> FWIW, I had a friend build the circit as well and he comes up with the
>same results.
>--
>Ron & Stephanie Tyler
>'72 LT1/T56 240Z
>http://www.whit.org/jcaudle/LT1-3.jpg
>