After hours of sweaty brows and much wringing of hands………..oh, alright, after a little bit of logical thought (first time for everything huh?)…..I’ve come up with what I think will be my final look at making a circuit to produce the Star Trek photon torpedo firing effect.
I’ve modified my original circuit by adding an extra 556 as a preliminary stage. It produces a fixed width negative pulse which in turn triggers the original circuit to produce a rising voltage to the selected led followed by a brief higher pulse (you can see the effect on the previously posted video).
The additional circuitry sidesteps the problem of latching up the monostables in the original circuit by making it impossible for the triggering pulse to be longer than the firing interval (you what?? Don’t worry ’bout it – it does work!!).
STOP PRESS – Still arsing around with this – I’ll post the final circuit when I’ve finally finalised it (duh!)
Ok, next thing is to get back onto the BOP to try and get that finished – then I can get stuck well and truly into my 1:350 Enterprise for which this circuit was cooked up.