# Rolling Your Own Wireless Communications System?



## BenFranske (Jan 23, 2004)

For those who read Slashdot you may have noticed the latest question on the front page is as follows:

_<a href=mailto:[email protected]>nuggetman</a> asks: "My high school, like most others, has a theater program. One critical element of the show is the tech crew - the group of people behind the scenes who keep it all running. Communication between the stage manager (myself) and crew members (as well as between crew members) is critical. For this job right now, we're using standard hand-held walkie-talkies. They get the job done, but they're susceptible to dead batteries, incompatibility between VOX headsets, and interference from janitors, the office, hall monitors, and even the local McDonald's. We've been wanting to invest in a theater-communication system, but they can run extremely expensive. Is there any hardware out there that could use a standard PC (Linux or Windows) and some wireless headsets to roll your own communication system that could cover a long enough range (say the theater which is the size of a gym plus a decent range outside it) at a low enough cost? Our school just installed 802.11b/g throughout the hallways, so we could tap into that if necessary and add our own router near the stage if we had to." _

I was appaled by some of the answers from Slashdot readers (who obviously do not understand theater at all) such as using laptops in backpacks and such. You can read all the responses on this page.

My response (to the laptop suggestion) was:
_You obviously have no experiance in theater. Techs are expected to do anything from crawling out over suspended ceilings to crawling under a stage or running up and down stairs during a performance. A laptop in any sort of arrangement would get in the way and be easily broken, nevermind that for the price of a few laptops you could buy a real system from someone like Telex or Clear-Com. I would suggest visiting ControlBooth.com and asking this question in their forums to get some practical suggestions. These are people who actually work with this day in and day out so they have real life experiance. Here's my idea to do this on the really cheap. It's not that hard to build a private phone network that doesn't actually dial but works like a party line, just put some voltage on the line. Get yourself a bunch of cheap cordless phones that allow headset use and lock the phones on so the line is always open. It's far from perfect but is the closest thing I can come up with off the top of my head. Don't take my word for it visit ControlBooth.com and ask in the forums, they're good people and know what they're doing._

What do you think? Any suggestions for this poor guy who is at the mercy of the crazy Slashdot suggestions?


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## zac850 (Jan 23, 2004)

Hum. Well, of corse, laptops are compleatly out of the question. "quick, everyone, lets go on AIM and talk about the cues". LOL. I wouldn't have exactly said it like that, saying that he clearly has no idea what hes talking about, but that idea would not work.

I am currently, or will be soon, looking for new Walkie-Talkies. My current set is compleatly bused, and only one walkie talky works well, which dosen't do very well during a show unless you want to talk to yourself....

Dose anyone know a good brand of HEADSET waklie talkie, or a walkie talkie that is cheep enough to but with a headset?

I've got till April, and I was thinking that I might just go to Radio Shack and see what I can find, but if anyone has any sugestions about brand/style of walkie talkie to use, please enlighten me

Thanks
Zac


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## BenFranske (Jan 23, 2004)

Really you're better off with a Telex or Clear-Com system. They do make wireless ones as well, and yes they are expensive but they are the standard for a reason. They hold up quite well and you can easily rent extra headsets and belt packs if you need them. They are an investment!

That said, if you are set on walkie-talkie's with headsets some things to watch out for... Most of the stuff you find at RatShack isn't powerful enough for your environment (all the steel, lights, power, walls, etc) besides if it's FRS it would be illegal to use for tech work (yes I know schools that have been fined by the FCC for this). You could get GMRS radios and buy a license ($75 for three years I think) which would be legal but not ideal for a number of reasons including range. This leaves you with getting a commercial license and commercial radios, this ends up being almost as expensive, if not more so, than a Telex or Clear-Com system and you loose the flexibility.

*That* said, your school may alread have a license and radios they use for other things and you could borrow for productions (just buy the compatible headsets) or even better some schools have commercial headset walkie talkies the football team uses for communication between coaches, these can be borrowed and work very well for a tech comm system in a pinch.


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## zac850 (Jan 23, 2004)

yea, ah, my school is to small to have a football team. If there was a football team, 80% of the school (guys and girls) would need to be on it...

I'll proubly just get some normal walkie talkies and buy the headsets (trust me, we won't get sued for THAT. maybe other stuff we do that are aginst fire coads, but not that


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## Damiena (Jan 23, 2004)

The high school David and I went to had a Prodcution Intercoms system installed, wired however. We never had any problems short of the need of just one more port. We placed headsets in strategic technical positions around the stage in case they were ever needed. Anyone who needed to talk to the Booth was always able to, but wireless would have been a great improvement to dragging XLR cables behind us. Once, our group was sent a a local theatre in town to help them, but without any intercom system at all. We finally improvised a system using two of our spare hearing impaired systems as one way communications devices. They worked horribly, but they got the job done.


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## The_Terg (Jan 23, 2004)

My techie buddies and I went out and bought NICE GMRS walkie-talkie's with earpieces and mics. They have range for half our town, they have no interferance - Advanced encoding - and they work quite well for our purpose. 

- And of course - PC communication is out of the question. I find no problems with our walkie-talkies, although they costed $140......

If they REALLY needed a telex or clearcom system, then I'd agree, wired would be best to start off with.


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## reidab (Jan 24, 2004)

In my high school theatre we have a clear-com system that we use for general communication but there are times on our larger productions in which it simply will not do. To remedy this, a friend and I hacked together a system by which to patch our clear-com output into our assisted listening devices. After completing this, we could give our stage crew boxes which would allow them to hear anything that went on on headset. We have two wireless microphones (1 lav, 1 handheld) which we gave to important crew members and patched their output back into the clear-com system. This allowed them to have two-way wireless communication using our existing equipment. Aside from that, I have had mixed luck with FRS depending on the space (all used on small productions). Another idea, if you are wanting to have use computers for this solution would be to install terminals on the sides of the stage which would run a custom software solution that would display cue information upon receiving commands from the stage manager. (I almost built this last year.) Also, a simple IRC system would work as well if you wanted text-based messaging but other than that, I think that a dedicated communications system would do you good.


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## The_Terg (Jan 24, 2004)

If you were REALLY intent upon using computers as a part of the communication system, then communication using them is fairly simple. As long as the computers are connected to either each other or the internet, you can fire up a voice chat program like Team Speak to be used as communication. Team Speak is free, and has a windows server that is easy to use. Then, grab AIM or IRC and you can transfer files.


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## ship (Jan 24, 2004)

I’m not so sure about it being illegal to use walkie talkies, I would assume the FCC has already assigned channels to them they will operate on that won’t get you in trouble. Otherwise , we would see episodes of “Cops” where the have to go into high speed chases against 8 year olds on bikes with them. But the subject was best discussed upon stagecraft about six months or less ago - all angles of it.

Humor aside, I once TD’d a theater that ran on so low of budgets that, let’s not go into that - it had very low budgets and no Clear Com.
We bought the Radio Shack walkie talkie system and we were within a brick building with huge windows and was right next door to a fire station - literally. We invested in the system to at least have something. Granted, the effective range was about where walls were not in place, and there was infrequent interference, but for the most part it worked really well and was cheap enough for the interested parties to just buy for their own personal use. There was also dual channels so you could switch should there be interference. The things had problems with headsets breaking, especially antennas not keeping hooked, but they worked well between the booth and stage for the cost. They were also very light - like a Walkman.

The next theater I worked at some time in about the 1950s had a telephone based clear com system installed in it that was still used when the clients were too cheap to invest in a Clear Com rental. Any drama club parents that work for the phone company can easily come by old specifications for switch board operator headsets and mouth pieces plus the power stations. Granted the headsets were extremely uncomfortable, and it took a power booster to hear anything, the system had been in place for about 40 years and still worked well. The only part of the entire system that had to be plugged in was the power boosters/amplifiers. Phone based systems work ok given it’s harder to find charcoal based parts for them now a days.

Next place I move onto started their com gear with a system from Kayos which still exists as a company. The gear was not that well refined, the components were very home made, but it worked. The company still exists and might be cheap in it’s control system. They use Buyer Dynamic headsets which are in my opinion high quality Euro stuff that’s comfortable to wear but high in cost. It’s all easily substituted with any other brand of headset however - you just have to reverse the jacks.

There is always E-Bay too.

After that, where I work they have some Production Intercom stuff. Decent equipment, not as refined as Clear Com, or as comfortable as Clear Com’s new equipment but the parts change out one for one and it’s cheaper. The ear speaker or mic element of a Production Intercom will be a cheaper direct replacement for Clear Com and you can mix and match systems. Say belt packs from one and base station from another. I believe in general that’s the case with most brands.

Clear com bought out another company that was good gear but cheaper, than adopted their design for their own. I thought it was Telex, but it’s possibly someone else. In any case, Clear Com is a good investment and they have a number of lines in gear based upon budget if memory serves.

There is at least two more intercom systems on the market that escape my mind also.

After that, my Nextel phone allows me to put a ear piece into it and communicate with groups of people instantly should I so want. That would be kind of pricy, but should the school’s maintenance staff or security staff have them in use, it might be possible to twist arms in using them on show nights. 

Networked computers giving a “Go”? That could work, after all before Clear Com it was flashing lights back stage that told the rail to fly stuff. There is various show control programs out there that are based directly off this concept. It’s also possible to just acquire a bunch of monitors and slave them to a main computer in presenting a single Go. Granted communication would be a problem from station to station, but a slaved bunch of monitors - which in smaller sizes are a dime a dozen should be fairly easy to come up with. Having a whole computer program with keyboards between terminals might be a bit more complex and distracting, but the idea of a “Go” light, and at best a way for booth to communicate with stage manager could work cheaply.


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## Nephilim (Jan 24, 2004)

ship: one more brand: PortaCom, made by Anchor Audio.

http://207.212.7.216/portacom.lasso

The headsets look a little clunky, but it's quite inexpensive compared to ClearCom's PL systems.


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## BenFranske (Jan 25, 2004)

Nuggetman, good to see you made it here to controlbooth.com I was one of the people who suggested the phone, based intercom on Slashdot. I've actually done these before myself and they do work, but I like to modify the phones to get rid of any noise they might make such as beeping when keys are pressed as well as add mute switches to them. That said a "real" intercom system such as a Telex, ClearCom or PortaCom really can't be matched by homebrewed solutions, I know, haveing tried about everything else myself.

Now that you've found us here I do hope you sign up for an account and stick around a while. I've been observing for a while and have been quite impressed with the group here.


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## The_Terg (Jan 25, 2004)

Sounds like a brilliant solution. Cheap, effective, simple.... 

Hmm, i may end up utilizing this if our school decides to skip the intercom system in our middleschool auditorium...


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## BenFranske (Jan 25, 2004)

Yeah, it's not pretty or perfect. I wouldn't recommend it in a high school, but for a middle school on a budget or an emergency situation it can be just the trick.


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## cruiser (Jan 26, 2004)

I just have to say, that i LOVE the telex wireless comm systems. I hired one for an event once, as oppose to getting motorola CB radio's (it was much cheaper and so much more practical). If only they wern't so expensive =(


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## Yellow_Fuzzy (Apr 19, 2004)

One thing ive been looking into is getting a set of CB Radio that support Quiet codes and headsets, so you just set the radio's lock the key pad and use the headsets. They arent too expensive and a 2W radio would probably be enough for most school or smaller theater uses.


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## dj_illusions (Apr 19, 2004)

I have a set of motorola units that I use for focussing or gigs that are outside where a wired comm set isnt practical and hiring a wireless comm set is generally a waste of time and money.

We have a few of them el cheapo crappo ones that you get from electronics stores.... the video crew uses them


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## dj_illusions (Apr 19, 2004)

I forgot to add, when looking for your general run of the mill walkie talkies to use as headsets, make sure they are duplexed. 

This means people can talk over the top of each other just like on your regular comm lines. If your have a conversation over it, as you do and someone is trying to give a cue... its just not gonna work.. so watch out for that!


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## Method9455 (Apr 26, 2004)

Hey,

I'm trying to switch from crappy walkie talkies to a clear com type system. i was thinking buying a production intercom like amp/powersupply thing (the ps-4 i think it is) and then build my own beltpacks like the comclone site shows. has anyone tried this? and how well does it work? I'm trying to get between 3-5 headsets on clearly, and I'm hoping to do it pretty damn cheap because our director won't give us money so its out of the crew's pockets. 

Kevin


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## mrtor (May 5, 2004)

cruiser said:


> I just have to say, that i LOVE the telex wireless comm systems. I hired one for an event once, as oppose to getting motorola CB radio's (it was much cheaper and so much more practical). If only they wern't so expensive =(



Jeremey

Not sure where you were getting your rental prices from, however a professional wireless system using Motorola Portables hooked into say a Clearcom or RTS wired talkback system should be pretty cheap compared to hiring the Radiocom system from Telex.

We are here in Melbourne, Australia and that is our core business providing talkback solutions both wired & wireless for rental and permanent installations.

A professional semi duplex portable radio system with the right gear is hard to beat IMHO.

Cheers
Mike


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## mrtor (May 5, 2004)

Method9455 said:


> Hey,
> 
> I'm trying to switch from crappy walkie talkies to a clear com type system. i was thinking buying a production intercom like amp/powersupply thing (the ps-4 i think it is) and then build my own beltpacks like the comclone site shows. has anyone tried this? and how well does it work? I'm trying to get between 3-5 headsets on clearly, and I'm hoping to do it pretty damn cheap because our director won't give us money so its out of the crew's pockets.
> 
> Kevin



Hi Kevin

I have been tinkering with the ComClone circuit for a while now. With some modification to some of the components as specified it actually works pretty good.

For the money, they are hard to beat. If you want the best unfortunately you pay a significant cost penalty to buy either Clearcom or RTS

Cheers
Michael


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## Method9455 (May 6, 2004)

I started building the system a few days ago, so far i'm about 1/2 way through the powersupply/base station thingy. I'm just waiting for the capacitors and 2 extra XLR plugs. 

What modifications did you do to improve it? 

Kevin


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## Method9455 (May 6, 2004)

I started building the system a few days ago, so far i'm about 1/2 way through the powersupply/base station thingy. I'm just waiting for the capacitors and 2 extra XLR plugs. 

What modifications did you do to improve it? 

Kevin


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## mrtor (May 6, 2004)

Method9455 said:


> I started building the system a few days ago, so far i'm about 1/2 way through the powersupply/base station thingy. I'm just waiting for the capacitors and 2 extra XLR plugs.
> 
> What modifications did you do to improve it?
> 
> Kevin



I don't have the information to hand at present, however it related to values of resistors around the duplex hybrid, the audio levels were too high to effectively work. I was actually pointed in the right direction by a fellow tinkering buff in Sydney, Australia.

I have since made up several for my daughters school as they did not have a budget to extend to Clearcom and they are kicking along quite happily ever since.

If you want some further details, email me off this board and I shall drag the specific details out for you


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## Method9455 (May 10, 2004)

Yeah i do want the details, are you saying you increased the resistor levels so that full duplex works? If so, can you pull up the specifics, I'm not great with this kind of electrical engineering, I was hoping to just put it together off someone else's plans, I can do that much without problems. And i don't really want to waste my own money, because I'm paying for it and donating it to hte school.

Kevin


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## mightythor (Nov 8, 2008)

Sorry about bumbing an older thread but I was wondering if the information in this thread would still be applicable?

I'm interested in the phone based DIY intercom. Are there any walkie talkie based systems that seem to work well?


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## avkid (Nov 8, 2008)

Charc said:


> I don't think the term "roll your own" can be applied to intercoms... :neutral:


Is someone's mind in the gutter?
This use is similar to "home brew".


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## lieperjp (Nov 12, 2008)

I find it amazing that of this thread Ship is the only one who is still active on this forum.


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