555 Calculator

"budgie"

They may be small, but they are sure smelly and plentiful.

....... Phil

Well, a lot of capstan motor servos on Studer pro audio tape decks used 555s for decades. They worked extermely well. I suppose the designer just new how to use them properly

martin

Without knowing the configuration it's a bit diffcult to comment. For all I know there is tachofeedback, in which event the repeatability factor is largely removed.

I=V/R if the output gets closer to the rail one way than it does the other

diifferent charge/discharge currents will result.

What youse guys failed to note in your circuit recommendations is that output freq varies with VCC. Since this application is a 12V marine elect. sys, variation in system voltage causes changes in motor RPM. Perhaps useful for something, but not for me. Modified the circuit with a 8V reg, since a 5V reg drops the output below TTL and the stepper board doesn't like it. BTW: this driver runs a stepper to rotate a radar antenna. Thus the RPM req. Variation in antenna RPM causes the display to lose sync. Back on track now.

JR North wrote:

I must admit I havent look at the typical Studer circuit in long long. But I was always astounded how good this little chip worked in the servo

martin

NOT MY RECOMMENDATION, DUMBASS!!!!!!! As usual with you f____g, know-nothing OPs, you chose the the IDIOT RESPONSE! You have only yourself to blame.

Using the single resistor and cap and CMOS timer, the frequency is

-Bill

"Bill Bowden" wrote in news: snipped-for-privacy@j73g2000cwa.googlegroups.com:

I think the umpire just ruled that one out LBW, the batsman standing on his stumps. Although that would probably be a different Bill Bowden? :)

Maybe you should take up flower arranging or something requiring no analytical deliberation whatsoever- you are clearly too mentally deficient for the electrical and mechanical trades.