wireless clear com??

[mbenonis]

Let's clear up a few things about the various parts of the spectrum that Wireless Intercom products tend to use (in the US, other countries may vary slightly):

VHF/UHF (174-216 MHz; 470-806* MHz)
This is the part of the spectrum that television broadcasters use. Many different products operate on TV channels that are not in use, such as wireless mics, intercoms, and the like. Technically, these products are only legal for licensed TV stations to operate (and only with a license for EVERY frequency in use), but this requirement is often disregarded for low-power devices (they actually operate under part 15 of the FCC's rules). Range is decent, and while interference is possible it is usually avoided by using RF coordination software or by doing hand calculations.

Commercial Radio (137-174 MHz; 450-470 MHz)
PI's WBS4000 system operates in this frequency band (the UHF one to be exact). This is the part of the spectrum in which commercial two-way radio operates, and a license is absolutely REQUIRED to operate here. Fines are quite high for those who disregard this requirement ($10k+). Range is very good, as power levels can be 5W+ on handheld units and into the 100's of watts for base stations. Typically systems are half-duplex, and only one wireless user can talk at once.

ISM/Amateur Bands (902-928 MHz; 2.4 GHz)
ClearCom's Tempest wireless system operates in the 900 MHz and 2.4 GHz bands. These devices operate under part 15 of the FCC's rules (like VHF/UHF), and thus have power limitations. Range is comparable to VHF/UHF systems, and interference (at least on 900) is reduced due to the relatively low use of the band. However, these systems must accept interference from other part 15 devices and licensed users (amateur radio operators, for instance).

Cellular Frequencies (1.9 GHz)
I am not terribly familiar with the 1.9 GHz band that ClearCom is claiming to use, but they do state that it is license free. I would also imagine they can use more power here.

The Bottom Line
All wireless intercom products will at some point receive interference. VHF/UHF TV products will be more likely to cause problems if not properly coordinated, but will likely work well if installed properly. 900 MHz is a good choice if the venue is running lots of wireless mics or is in a congested RF area, but problems will be much more difficult to resolve because of less control over other users of the spectrum. 1.9 GHz has the potential to be the most reliable band, but I don't know much about it and who else is using it.

*After February 19, 2009, the UHF TV spectrum will extend from 470-698 MHz. Devices that operate above 698 MHz will have to be replaced, as the 700 MHz band will be licensed to public safety and wireless companies (and you don't want to incur a fine for causing interference).

 

[gafftaper]

My research on the topic... as has sort of been confirmed by this thread... is that wireless clear com is a bit of a crap shoot. You can pay a lot of money and get something that still has issues. I'm intrigued by the Eartec Digicom system. The Digicom system is 900 mhz, digital spread spectrum technology, and it's full duplex. For about $2500 from Markertek.com you can get an interface station, 3 belt packs and headsets. The interface just plugs into any clear com jack and you are ready to go. Or you can use the three radios as a complete stand alone system. I still haven't found anyone who actually owns one to tell me how they like it or not. But someone around here (Icewolf I think) uses one of their headsets and likes it.

 

[icewolf08]

Using a headset and liking it does not qualify me to talk about any of their other products. I believe eartec started with headsets, and I know they do that well. As for wireless coms, I have no idea.

The system I really would love to test run is the Clear-Com Cellcom sysem. It sounds like a great system. We just installed one of the new ClearCom WBS systems, and it has worked great. Before we were using one of the Telex systems and it was lousy. That's my two cents.

 

[kwotipka]

From experience the Telex BTR systems are excellent and rock solid IF they are setup correctly. It always annoys me when the sound dept just unpacks the wireless rigs and leaves them "as is". You should always check at least with an intermod calculator to see if you might have issues. Shure offers a frequency suggestion somewhere on their website for your area of the country.

The two things I would throw out is:

1) Make SURE that what you are getting can run in the unlicensed part of the band or get the licenses.
2) Do some homework and see what is going on in that part of the band first. A hand held scanner or help from a local HAM could save you some issues.

I think a ham radio license should be a requirement for anyone dealing with wireless gear.

kw

 

[mbenonis]

2) Do some homework and see what is going on in that part of the band first. A hand held scanner or help from a local HAM could save you some issues.
I think a ham radio license should be a requirement for anyone dealing with wireless gear.
kw

I wholeheartedly agree with this. A wireless tech's best friend is a scanner or HT with wideband receive. I know it has been useful for me many times when debugging issues.

kwotipka, do you have a ham license?

 

[kwotipka]

kwotipka, do you have a ham license?

Yep, KD5QYV. Was past ARES EC for the parish. Provided coordination between Red Cross, Medical, law enforcement, etc at the second largest shelter (Lafayette Cajundome) for the Katrina evac. We had POTS, T1/T3, Fiber, cable modems, Sat, VoIP, SIPs, etc. It was a mess.

Currently APRS Igate/digi manager for the RF region. Teach radio merit badge at local winter camp for past 4 years. Yea, I guess you could say I am a ham although my truck only has one antenna on it! (Besides factory FM).

kw

 

[mixmaster]

I know this is about a year old, but has there been any new info anyone can pass on? I am looking to supplement my current wired clear-com system, but clear coms wireless for 4 belt packs is around $12,000.

We also have a wireless system that we can plug in to the wired clearcoms in eaither of my venues on campus, or the comm circiut for the TV station and camera crews. We can also use it as a completely stand-alone system when we set up in a room that does not have any current intercom system. When interfacincing with a wired system it plugs in to the same 3-pin xlr that one would normally plug in a belt pack. We have Clearcom, Telex, and some other brand and the wireless unit works with all of the above.

The unit is a Telex BTR 200 II. it provides 4 wireless belt packs and a headset at the main control unit, witch is a single rack space unit. The headsets that came with the beltpacks are the lightweight single ear types that wrap around the back of your head and have small earpeices that dont get in the way of my headphones. We have also ssuccessfully mixed and matched with other headsets in our stock. Two of our beltpacks even provide phantom power for condenser mic elements. The beltpacks operate with 6 AA batteries and we can get 6 to 8 hours of normal use on NiMH rechargeables. The system operates in the 600 megahertz band. We occasionally get some interference with wireless mics but careful coordination of frequencies when we order wireless stuff has minimized that. It has never received or caused interference with any other systems and has enough of a range that I haven't found the edge of it yet.
Perhaps the best thing about it is the way it works as its own system. We use this feature to provide intercom communication when we do shows outside of our traditional spaces. (conference center, fieldhouse, outside,) We give it power and there it is.... communication. If we need more than four wireless stations we take an audio out from the intercom unit and feed it to our assisted listening system transmitter in the same rack The we have the 4 two way beltpacks and up to 10 listen-only stations (good for camera crews, video monitors and ushers/house crew).
Unfortunately, I don't know the price. It was purchased before I was hired here and I can't find the PO records. Telex is typically not as expesive as Clearcom or other "name brand" stuff though.
Best of Luck

 

[roxytech]

im a technician at an old theatre, and we have a really old clear com system that is wired through the building...im always running all over the place in the building so i was wanting a wireless interface kind of....if u know what i mean...we have the old packs(in 3 prong) and old headsets(4 prong)i don't know if there is such a thing, but is there a way to replace XLR cables with a wireless one??? i know sounds real crazy but like have a transmitter and a reciever so i can plug the transmitter into the back of the unit, and the reciever into the other unit?

 

[mnfreelancer]

Roxytech - that's what much of this topic has been about - a "jump" interface made by EARTEC. Nobody seems to have used one so I can't comment as to how effective it is but it's relatively cheap - but that's the rub, cheap is relative. I guess $1000 isn't really that cheap if one is to buy a personal rig, as opposed to the company. Anyway read the topic more carefully and you should find some info.

Relatedly I've considered building such a set-up before but haven't had the time to design it or even really conceptualize the electronics needed (ee major). Maybe someday...

 

[icewolf08]

im a technician at an old theatre, and we have a really old clear com system that is wired through the building...im always running all over the place in the building so i was wanting a wireless interface kind of....if u know what i mean...we have the old packs(in 3 prong) and old headsets(4 prong)i don't know if there is such a thing, but is there a way to replace XLR cables with a wireless one??? i know sounds real crazy but like have a transmitter and a reciever so i can plug the transmitter into the back of the unit, and the reciever into the other unit?

Really the best way to implement any wireless coms is to get a real wireless coms setup, like the Clearcom WBS-670/680. The base will connect in to your existing lines and then provide one or two channels of comms to 4 wireless packs. It isn't cheap, but it is designed for the theatre/production world. You will also get the best reliability and customer service from a major player like Clearcom or Telex.

By the way, you may want to stop by our New member forum and introduce yourself, we love to hear about everyone!

 

[mnfreelancer]

On a little bit of an aside from the immediate topic, back in highschool I worked for both the theatre and the access tv station that was based in the highschool. Access bought a fleet of 6 5 watt commercial motorola radios that I used extensively in setting up equipment for both theater and video. I also used them as a link to my stage runner when running the sound board from the booth. I dreamed of having an interface that could bring the radio to the wired clearcom system we had. Now such a device exists and I wonder how exactly it interfaces the half/duplex 2-way radio to the full/duplex intercom system. It almost has to use some sort of VOX system for when there is actually audio on the intercom side. Otherwise, you wouldn't be able to key your radio to talk on the intercom. That also brings up the problem of talkover - with the intercoms you can talk over chatter if something important comes up (you shouldn't chatter on comms but everyone does), but on the radio if there is already audio you wouldn't be able to key the remote radio. Then also if you run any program audio over your intercom as some setups allow. Makes me woner...

 

[Wolf]

In my opine dont buy cheap wireless coms of any brand. When ive used cheap ones you will always get static NO matter what you do. I have never had this issue but ive heard it has happened - but on cheaper ones you can get interference from other form of wireless devices such as truckers and radio and cell phones. This us just what I think. Many people do buy cheap wireless and are happy with them.

 

[Malabaristo]

I dreamed of having an interface that could bring the radio to the wired clearcom system we had. Now such a device exists and I wonder how exactly it interfaces the half/duplex 2-way radio to the full/duplex intercom system. It almost has to use some sort of VOX system for when there is actually audio on the intercom side. Otherwise, you wouldn't be able to key your radio to talk on the intercom.

There's a simpler solution to the half/full duplex interface problem: use something that's already full duplex. To add a couple of wireless sets to my self constructed, Comclone based*, system I bought a couple of cheap Plantronics CA-10 headsets off Ebay. They're designed to go between the handset and base of a standard telephone. All that was required to interface them was impedance and level matching. In this case, I was able to do that just by changing settings on the Plantronics base station and making an adapter cable to connect with the headset jack of my beltpacks. They also work as well or better than the Telex wireless that I've used once before (though I don't know what type that was specifically or whether it was set up correctly).

Granted, the Plantronics units are 900MHz, so you could be at risk for interference with other products... hasn't been a issue for me yet.


*Note: I had some problems with RCrowley's exact design; incorrect component values and such. PM me if you want more info on this or the wireless part.

 

[Sayen]

Van, I'll do everything I can to start gig jumper here. I like that term, and people at work seem to enjoy stealing my fun projects. Gig jumping me?

I love this place - I've been dealing with the same issue, trying to add a simple wireless component to a wired intercom, which is probably why PI and EARTEC developed their respective products. Doing the system right looks great on paper, but is very expensive for a marginal increase in flexibility. For the same price as a wireless Telex or ClearCom system, I can purchase a hefty load of lighting gear, more mics for actors, etc. An economic solution, even with static and the occasional interference, is workable.

So since this thread was started, no one has tried the EARTEC setup? Or can speak to the quality of the Production Intercom wireless? In my case, I chiefly want one for myself, but can't justify the high cost for my own convenience as a teacher.

I like Malabaristo's concept, I may have to play with that.

 

[Spiceboy]

Although this topic is a little old now I thought some of you might find it useful to know that you can interface standard 2-way radios to a wired system using a device called a TW40 or TW47.

The wiring will depend on the 2 way Radio that you are using and may be a little tricky less common models. It gives you access to one channel but there are ways to set things up if you need more. Obviously it wont give you the same audio quality as a wireless but it should give you a workable solution on a budget.

 

[Sayen]

Thanks for the idea.

Has anyone tried the EARTEC system?

 

[DaveySimps]

I got a demo of the eartec units a couple of years back. We had them for a few weeks. They worked well, but we did not end up buying them. For the price, I thought they were to poorly made. The headsets were VERY cheap in quality, especially the light weight ones. I was worried they would not hold up. If they were to come out with a more rugged design of the plastic components for roughly the same price range, I would absoultely reconsider. They did interface with our wired Clearcom system quite well though.

~Dave

 

[CCFDMX512]

Now to revive a REALLY old thread. We have a wired Clear-com system and a Telex BTR-300 which I would like to start using to give the production manager some roaming capability as well as for the stage manager to be able to receive cues from the PM since there is not a wired station near the green room. My problem is integrating the BTR-300 with our clear-com system. The clear-com uses a 6 pin connector while the btr uses a 3 pin. Is there an easy way to make an adapter or a cheap pre-made adapter for sale? I don't need the telex to be 2 channel like the clear-com system is, 1 channel is plenty. After reading this thread I haven't seen this issue addressed yet. Thanks!

Edit: After posting this I did some digging around in the production room and found an adapter cable that was made for our systems which splits the 6 pin into 2 3 pin connectors, one for channel A & one for channel B. The system integrates well but there is a lot of static when I get too far from the base with at least 2 of the packs. and when I say too far I mean from FOH to stage left. It seems that the range should be better than that. I'll test the other 2 packs tomorrow. I'm guessing this is the reson why this system was just thrown on a shelf in the back and not being used.

 

[tyler.martin]

The HME DX200 interfaces with all wired com systems quite well, they are relatively cheap as well from what I can remember. The wireless quality is really dependent on where the base station is placed, but I put one inside a steel room on a ship and still got good quality signal 150 feet away

 

[Edrick]

Now to revive a REALLY old thread. We have a wired Clear-com system and a Telex BTR-300 which I would like to start using to give the production manager some roaming capability as well as for the stage manager to be able to receive cues from the PM since there is not a wired station near the green room. My problem is integrating the BTR-300 with our clear-com system. The clear-com uses a 6 pin connector while the btr uses a 3 pin. Is there an easy way to make an adapter or a cheap pre-made adapter for sale? I don't need the telex to be 2 channel like the clear-com system is, 1 channel is plenty. After reading this thread I haven't seen this issue addressed yet. Thanks!

Edit: After posting this I did some digging around in the production room and found an adapter cable that was made for our systems which splits the 6 pin into 2 3 pin connectors, one for channel A & one for channel B. The system integrates well but there is a lot of static when I get too far from the base with at least 2 of the packs. and when I say too far I mean from FOH to stage left. It seems that the range should be better than that. I'll test the other 2 packs tomorrow. I'm guessing this is the reson why this system was just thrown on a shelf in the back and not being used.

If you're unable to get your BTR-300 unit to work I'm looking for the grey button that's on the portable station buttons and the antennas.

But for your issue does the unit have both it's antennas and are they the full antennas? Each antenna is two pieces that screw together. Also are your antennas inside a rack that could be blocking resection?