Need a solution for wireless practical

[Patzmcc]

The director of a show I am currently ME-ing has asked for a (practical) floor lamp to travel around stage throughout the show, "and could it be wireless?" does anyone have any suggestions as to how to execute this? I realize the more control I give up the easier it becomes, but I do hope to have DMX control as well as dimming capabilities. The lamp does have a fairly large shade that will make hiding equipment easy.

 

[oneeyedpug]

I would use RC4 Wireless Magic

http://www.theatrewireless.com/

 

[dbaxter]

The RC4 is probably your answer for the wireless dimming part. For wireless power, I've used a computer UPS - with the beeper disabled. With an incandescent 40W bulb you can get several minutes of 'on' time with a reasonable sized unit. For longer times, you could use an LED bulb, if the RC4 can dim it. With that, watch for a snap on-snap off effect at the dim end of the fade (again dependent on the RC4).

 

[sk8rsdad]

We did something similar with a lamp for our production of "The 39 Steps". Ours was a homegrown wireless solution with a 3W RGB LED and a Lithium Ion RC car battery. Everything was hidden in the lampshade.

 

[Patzmcc]

RC4 has exactly what I am looking for but unfortunately is out of my budget (we don't want to blow the entire lighting budget on one practical).

We did something similar with a lamp for our production of "The 39 Steps". Ours was a homegrown wireless solution with a 3W RGB LED and a Lithium Ion RC car battery. Everything was hidden in the lampshade.

A homegrown solution I think is more to our budget. The designer really wants it to be dimmable and that is whet I'm hung up on.

 

[sk8rsdad]

I will see if i can get the details from our resident electronics wizard. He's published a lot of the designs over at doityourselfchristmas.com and may have some prototype PCBs available.

 

[derekleffew]

RC4 has exactly what I am looking for but unfortunately is out of my budget (we don't want to blow the entire lighting budget on one practical). ...

Did you see the Rental Page? Or is even renting beyond the budget?

 

[rochem]

Northlight DMX makes some good affordable products that might work for you. You still need to deal with the battery power, but the Northlight PCBs will take in DMX and output either a relay signal and/or control voltage.

http://northlightdmx.com/DMXtoRelay.htm

 

[sk8rsdad]

So I have an update on the homegrown option.

The latest generation is in development with PCBs arriving in the next few weeks. This version is designed to support a full DMX universe and standard refresh rates. LabRat's posted pictures of the DMX/NRF transceiver here. There's a compatible NRF/3-channel LED driver board to go with it which would go on the fixture.

Timing-wise you may be better off with a commercial solution.

 

[TheSwami]

The RC4 would likely be your most flexible/programmable option, but depending on how much control you actually need and how handy you are with a soldering iron, a couple options might be:

If you just need to practical to dim as the stage dims (and turn off for blackouts), you could use a Light Dependent Resistor surreptitiously mounted on the outside of the practical. (i.e. Somewhat it's not going to be hit from the light of the practical itself). If you wire your light source to be controlled via a suitable transistor, the practical can turn on whenever it "sees" light and turn off when it sees dark. (The example circuit is for an LED source powered by 5V. Higher DC voltages are possible for suitable transistors and LDRs; for higher AC voltages, such as those provided by a rectifier, consider using this circuit to drive a relay.)

If you need somewhat more control than that, and your stage size is small enough, I've have partial success with wirelessly controlling props with Adafruit's keyfobs and wireless receivers. I've used them primarily to trigger microcontrollers, but there's no reason you couldn't use the latching-type receiver to control a transistor or relay to turn a practical on and off. Fair warning - much light a car's keyfob, successful operation depends a good deal on the relative distance and orientation of the transmitter and receiver. I've had pretty good results up to about 50' with direct line-of-sight.

 

[chawalang]

This is a set up I have for a tour that I am on. Its used for a desk lamp on a desk that gets pushed on stage on a pallet. It is also used in another prop that looks like a walker with wheels that has two lamps in it to look like a car. So both aplications have the unit moving all over the stage.

 

[blackisthenewblack]

If you need somewhat more control than that, and your stage size is small enough, I've have partial success with wirelessly controlling props with Adafruit's keyfobs and wireless receivers. I've used them primarily to trigger microcontrollers, but there's no reason you couldn't use the latching-type receiver to control a transistor or relay to turn a practical on and off. Fair warning - much light a car's keyfob, successful operation depends a good deal on the relative distance and orientation of the transmitter and receiver. I've had pretty good results up to about 50' with direct line-of-sight.

This is probably the cheapest option at ~$100 for parts - LED, Microcontroller, remote, battery.
The key is to keep everything at the same voltage. We have had issues with a 3.7v PCB, 3.7V battery, but the remote wanted 5V, so it wouldn't work "properly" (see what I did there)

 

[Narf]

Hello (and Greetings),
New to CB, and was wondering how things went with your quest for the "Wireless Practical"? What was the outcome? (any pictures?)

 

[Jay Ashworth]

In case any of y'all didn't know this: you can buy standard medium-screw base 12V lamps at most marine stores, like West Marine. A 12V SLA/AGM battery is most of the weight of a UPS, and just going 12VDC direct is *much* more efficient.

And, unsurprisingly, you can now get 12V *LED* lamps in that base as well:

12V AC/DC E26/E27 (Medium) LED Bulb | A19, PAR20, PAR30, G4 Bulbs | Super Bright LEDs