Really, really simple strobe control

[pritch]

I need to manually trigger a strobe. Just single flashes, no variation in speed, intensity or whatever. As ever, this needs to be done on a budget of virtually nothing. So here's my question:

 

If I have a push switch, and a 9v battery connected to the analogue control socket on a strobe fixture, would a single press of the button result in a single firing?

 

Going from what I've read elsewhere, this would appear to be the way things work, but it all seems far too simple!

[Jamtastic3]

An analogue strobe only needs between 0 and 10V so if you stick a 9V battery in the equation, I can't see why it wouldn't work.....? Remember though that your actual strobe unit will need 240V power.

[niall]

All you can do is test! I believe some strobes will continous strobe if the button is held down, so you could always incorporate a capacitor and a two way switch, so that when the switch is set to position 1, the battery charges the capacitor. Set the switch to position 2 and the battery is disconected and the capacitot discharges through the strobe. The discharge should happen very quickly and result in one flash.

[Wuddy]

With analogue control 0 - 10v does speed increase with control volts? flash rate with 9v might be fast enough to get more than one flash with the button push. What about using a 1.5v battery giving slower flash rate so less chance of multiple flashes.

[Stuart91]

My experience of Pulsar strobes is that they don't strobe continuously on application of the voltage - they simply flash when they see 10v or thereabouts. It's relatively easy to hook up a strobe to the output of an analogue desk or demux. I hadn't thought of using a battery though - that's kind of neat...

[musht]

With analogue control 0 - 10v does speed increase with control volts? flash rate with 9v might be fast enough to get more than one flash with the button push. What about using a 1.5v battery giving slower flash rate so less chance of multiple flashes.

 

Its a 10V pulse in on a 1/4" jack rather than 0-10V speed control, from back in the day when a 4 channel strobe controller with more than one pattern was exotic.

[dbuckley]

And the 10V pulse needs a decently short risetime; a Showtec demux does not qualify :D

[greenalien]

would a single press of the button result in a single firing?

 

You might want to put a small capacitor - say 0.1 microfarad non-polarised - across the switch, otherwise it might trigger more than one flash. However, your idea seems basically sound and should work.

[Don Allen]

Try the capacitor in series with the switch so it acts as a differentiator and gives a short pulse. If it is across the switch it acts as an integrator. Passive Integrator and Differentiator circuits

[swampman]

Push button + 9V battery positive to tip , ring to 0v on 1/4" jack will do the works for Pulsar Jumbo Strobe for manual "lightning FX".

Just used in a kids low cost show. Remember to switch the auto flash speed to "off".

[pritch]

Excellent stuff, thanks everyone. I'll try just the battery and push button at first, if that doesn't work then I'll try stuffing some extra components in there as well.

[KevinE]

Yep it very much depends on the make of strobe..what have you got? The Pulsar Jumbo and Monster for example give one flash per 10V pulse (ie fed off an astable controller) whereas the Anytronics Deathstar has a repeating input which just needs a button and pot in series. The Soundlabs, Geni, Source etc give multiple flashes at logic high input with a setspeed pot on the rear. They're all different!

 

A capacitor in series with a push button wont work, it will flash once and then stop because when you take your finger off the switch the capacitor will be isolated and thus still fully charged. You'll have to introduce a discharge resistor or else use a changeover pushbutton.

[nightster]

Hi Guys,

 

Sorry to ressurect an old topic, but I;m trying to do something fairly similar.

 

The difference being, that I need the strobe to fire completely randomly.

 

Is there such a controller around? Or could something be adapted to give random fire?

 

Many thanks for any advice!

 

Cheers,

Rob.

[nightster]

No ideas guys?! There MUST be something out there...surely?!?

 

Thanks!!

[fitz_e]

Electronics doing something random? One method that springs to mind is to use a random signal source (audio recording of speech, anything that has no 'rhythm' or pattern) and a Schmidt trigger (basically a gate that either opens or closes when its input goes above a certain threshold). When the noise goes above a certain level, the gate triggers which fires/triggers the strobe; offset the input to the gate to select a higher/lower frequency of flashes. Think how the peak LEDs on an audio mixer can trigger fairly randomly when a signal source e.g. vocal, is close to the peak limit of the system. Second method: employ/persuade/cajole someone into pressing a button.