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If you need synchronized pulses from identical timers, why are you using more than one timer?...with the same charging and discharging circuit.
Not possible. Each multivibrator has to have its own timing components. You may use the same values for different multivibrators but then they will not all operate at the same frequency due to tolerances.Same charging and discharging circuit is shared by all multivibrators.(Frequeny is 3kHz)
Not possible. Each multivibrator has to have its own timing components. You may use the same values for different multivibrators but then they will not all operate at the same frequency due to tolerances.
But: As all timers shall output the same pulses, why not use a single timer and distribute the output signal to the different loads as suggested by Laplace in post #3? Are we missing something or are you not giving us the full information?
I'm sorry, but I don't seem to understand. If a bunch of monostable multivibrators is triggered by the same input signal, the outputs are scnchronized (with respect to the input signal). If the multivibrators have different timings, then the outputs will be active at different times as defined by the respective timings. If the outputs shall have the same timing, a single multivibrator suffices.
Can you draw a timing diagram showing inputs and ouputs to explain in more detail what you want to achieve?
@Harald Kapp has already told you that it is impossible to synchronize the pulses from independent astable multivibrators even if all have the same RC timing components. Moreover, your "triggering" inputs appear to be asynchronous, so why would you expect the output pulses to be synchronized with anything? And why are you applying your external "triggering" signals to the Vcc input of each astable multivibrator? Why not use the INHIBIT/RESET input of the 555 timer and leave Vcc applied at all times?
Many years ago, while working with Texas Instruments SN74xxx series TTL integrated circuits, I had the problem of synchronizing an asynchronous external event (a switch closure IIRC) with the clock signal used by the logic. It was important that this external event not result in a truncated output pulse because of asynchronous timing between the real world event and the independent clock transitions. Just in the nick of time, I discovered that Texas Instruments had solved my problem with a dual pulse synchronizer integrated circuit, the SN74120. Unfortunately this part is now obsolete, although you may still be able to find a few. Or, you can build a discrete logic version using the schematic provided on the data sheet. With this part, you use just one clock generator, replacing all your "astable multivibrators" with one pulse synchronizer for each input.
One other point you may want to keep in mind is that the 555 timer is an IC that can not be used when precice sync pulses are required. Also its output can be affected by ambient temprature. This IC is generally used in simpler circuits that dont require sync of high accuracy.