"Jasen Betts" wrote in message
...
On 2005-12-25, Henry wrote:
Hi, dabbling with some TTL stuff that I dug out of storage. Im about 25
years rusty since I tinkered with this stuff all those years ago.
Anyway,
working on a project where it would be deal to have a 555-timer based
monostable multivibrator (with retrigger ability.) Is that possible with
the
555? I have found many circuits online (actually mostly the same one
over
and over again) but they dont seem to support re-triggering with the
555.

if by retrigerable monostable you mean have it restart its timing interval
while in the "on" state, no that can't be done using the 555 alone.

the 555 operates by charging (or discharging) a capacitor. to restart the
interval you'd have to arrange for the capacitor to be discharged back to
its starting voltage.

Bye.
Jasen

Okay, thanks. That foils my one idea. I have an old SN74123 Dual
re-trigerable monostable multivibrator. I had simply hoped that a single 555
timer could do the same so that I did not have to waste half the 74123
package. I only have a couple of these and no funds to acquire anymore of
them at the present.

Henry