Thanks
today I changed configuration as below but the result was not good.
remove diode, connect emiter with R10K to -15VEE, chnage 330K to 10K, connect base to -15VEE with R10K,
change R150K to 47K
only a 1nF cap between opamp output and its negative input reduced noise to 50mv (equal supply...
Thanks All
Also before there was a RC(1K,2n2) between collector and base that force circuit to oscilate, other values for C (20p to 100n) didnt produce good results.
because of low output impedance of +100V supply source, I have to use this resistances values, but if you think change of...
hi all
my voltage booster circuit {http://john111smith.googlepages.com/vbstr.png}
shows the following noise levels:
A: <+-50mv
B:~ +-200mv at 67v output
D:~ 0
OpAmp: OP07 or LM741
How can I reduce noise level at point B to about +-50mv?
Also, there is some produced gas at vaccum chamber during work of system, that change level of vaccum at random events. (Turbo pump works constant.) So, controller via valve must stablize adjusted level of vaccum.
I hope the control be simple :)
I going to use only final stage [U6/Q1] of the...
the above circuit extracted from a mono layer old PCB.
because of simplicity, I didn't place 10K potentiometers (offset null) of all 741 opamps circuits. and also, RC [1k, 2n4] between B and C of Q1.
R37 is 67K7
the ouput is enough to drive piezoelectric voltage controlled valve.
if its...
the above circuit extracted from a mono layer old PCB.
because of simplicity, I didn't place 10K potentiometers (offset null) of all 741 opamps circuits. and also, RC [1k, 2n4] between B and C of Q1.
R37 is 67K7
the ouput is enough to drive piezoelectric voltage controlled valve.
if its...
Hi All,
I wish you a Merry Christmas and a Happy New Year.
I try to use a PID controller instead of an old hardware vacuum controller. While, a turbo pump decrease pressure; a valve connected to the vacuum chamber, increase pressure.
What is the equation that represents the function of the...
Hi All,
I wish you a Merry Christmas and a Happy New Year.
I try to use a PID controller instead of an old hardware vacuum controller. While, a turbo pump decrease pressure; a valve connected to the vacuum chamber, increase pressure.
What is the equation that represents the function of the...
thanks
but it will not work with LOOK-UP TABLE
- input is voltage for gas paffing valve control
- turbo vaccum pump run continuously
- output is vaccum
