Project Box (#270-1801)
E-5 Lamp Holders (pkg. of 2, #272-340)
Mini #222 Lamp (pkg. of 2, #272-1176)
Battery Holder for 2 AAA (#270-398)
Mini-Clips (pkg. of 12, #270-380)
Micro-Mini Toggle Switch (#275-624A)

There are a few other misc. items needed, but they can probably be found without making special purchases, i.e., a small length of small gauge wire, a small piece of thick foam rubber, etc.

The project box has "feet" which I made the inside or back of the transmitter that would be facing the figure. This leaves the lid and the screws that hold it facing "out", but you can paint the screws black when you're done and they won't be noticeable.

The first thing to do is to drill a few holes in the project box.
The first hole will be in the top for the lamp holder which I put right in the center of the top.
Now decide which will be the front edge of the transmitter, i.e., if you hold your figure on the right and the figure wears the unit on it's right. Once you have determined that, drill a small hole towards the "back" of the top edge of the box, this will be for the "wire" leading to the mic.
Next, you will need to drill a hole for the switch along the "back" edge of the unit (I centered it).
Last, a small hole will be needed in the back for attaching the "belt clip".

Now you can hot glue the battery holder in place (I drilled a hole and screwed it down, but realized afterwards that gluing would work just as well and be easier).
Next, install the lamp holder and switch.
Now comes what was the most difficult part of the project for me, soldering the connections. I've never gotten along real well with soldering and would have preferred to use a liquid solder, but couldn't find any at the time. Afterwards, I found out Radio Shack has one.

However you do it, you need to attach one of the red wires from the battery holder to one of the connection prongs on the switch and the other red wire from the battery holder to one of the connection prongs on the lamp holder.
You will now need a very small length of small gauge wire to connect the two "empty" connection prongs on the switch and the lamp holder.

Once the connections have been made, insert two AAA batteries and a lamp into the lamp holder and give it a test. It works? Good! Now screw on one of the lamp holder lenses - they give you white and red ones, I used the red myself, but whichever you prefer - there's no rule.

Okay, now before you screw on the lid, you need to do two more things.
The transmitter needs a clip. Take one of the "mini-clips", and either find yourself a very small screw and nut to attach that with through the hole you drilled for that purpose or (and I didn't think of this until afterwards) but I imagine you could attach it with a cotter pin just as well through the hole.

Now for the "mic" wire.
For this, you can use a length of any small gauge black wire or hollow flexible tubing. If you cannot seem to find either, you could use string painted black, but this will not look quite as "realistic" if you ever get up close to anyone with the unit on - but it will look fine from stage distance.
The length of this will depend on your figure(s). I made mine excessively long on purpose to cover a variety of figures and to also heighten it's visibility with it "hanging out there".
Whatever you use, insert one end through the hole you drilled behind the light and knot the end so that it cannot pull out of the hole, and go ahead and put the lid on the box and screw it down.

Alright, the "transmitter" is done, now we need to make a "mic" for this unit.

For this, I cut off about an inch from a 1/2" dowel I had sitting around, drilled a small diameter hole through the length of it, and a small diameter starter hole in the side, and painted it black - and while you've got the paint out, go ahead and paint one of the mini-clips black also. Insert the free end of the "mic wire" through the hole that you drilled lengthwise and knot it so that it can not slip out. Then attach the mini-clip to the dowel with a small wood screw into the starter hole.
Now as luck would have it from being a "pack-rat", I had a 2" thick piece of gray foam rubber from which I cut out a round ball for the head of the mic. If you don't have gray foam rubber handy, white will work too, it will just mean painting it either gray or black.
I also cut into one end, a bit of a recess in the ball for where it attaches to the "mic". So now a bit of hot glue over the end of the mic and the knot which helps hold it in place, and then place the "ball".
(Don't forget to paint the screws on the lid of the transmitter black, and there you go, a "dummy wireless).

SOME FINAL NOTES

The materials I listed as having been bought from Radio Shack came to about ten dollars, and this could cost you a little bit more if you need to buy any of the other items like the small gauge wire, etc.
You could build something like this a bit cheaper if you have a lot of misc. "stuff" laying around in a workshop, I did one from "scrap stuff" before building this one, but I do have to say, this one does look a lot neater.
When writing this idea up for the transmitter with a light, my goal was to, as much as possible, use parts that anyone could get anywhere.

Also, some may find the sizes I've chosen for things like the "mic" or even the lamp on the transmitter a bit large. I did this not only because I want them to be noticeable, but because I often view figures and the things they say and do as a caricature or exaggeration of "real" people, and so things associated with them should be the same (in my opinion).

Of course, I've only attempted to relate a way to do this project, you may decide to use materials you have handy, or come up with a better way to do part or all of it - if so - good!

A performance tip?
Well, there's the obvious one I use - When the figure first starts talking, they're not quite audible, so you ask if they turned on their mic, and as you do it, the figure's voice suddenly comes through loud and clear in mid-word.
And of course you can reverse it for the ending too, after the figure cracks some wise remark, you tell him you've had enough, you're shutting him off, and as you shut off the switch, his voice again becomes inaudible in mid-word as he's protesting you turning off his mic.
(The light coming on and going off adds to the effect of it being a working mic that's just been turned on or off.)

Have fun!
Dave

Picture legend;

A: Hole for light
B: Hole for mic wire
C: Hole for toggle switch
D: Hole for attaching belt clip
E: Wire from light to battery box
F: Wire from battery box to switch
G: Wire from switch to light