GMRS, MURS and DTR Digital at Disney World

[matt131]

Hi Everyone,

I wanted to share some information with everyone but also ask for your information and input on using GMRS, MURS and DTR digital radios at Disney World.

I have used 4 watt GMRS radios at Disney and the range was ok. There are a number of repeaters in the area but from different parts of WDW you can't get into the repeater. For example while at Downtown Disney the Celebration repeater worked excellent. When I went up to Magic Kingdom I couldn't hit the repeater at all. I also found a lot of interfearance at Magic kingdom probably from all the electronics throughout the park.

I wasn't impressed with 2 watt MURS Again with what I believe to be interfearance from electronics in the parks the MURS units didn't transmit very far.


Now the impressive radio!!!

I found the Motorola DTR units to work excellent. I found them to actually have better coverage than 4 watt UHF/GMRS units. The nice part about these units is if you wheren't in range of the other radio you could see that on your screen because it would say "user unavailable" Also if you had multiple people in your group you can call the one person on the whole group. I found these units very useful.

One example I was in the elevator at the beach club resort and my family was at EPCOT and they could call me no problem.

Does anyone have any comments or stories I would like to hear them.

Thanks,

 

[wkredick]

I have had better luck with DTR 900mhz than MURS 2watt VHF outdoors in most cases.Recently on a caribbean cruise ship,was able to talk from top deck bar down to 8 floor below deck to room.
Also stern to tail outside.The 1 on 1 is a big plus too if you want to gossip about another DTR user w/o them knowing .

 

[tekshogun]

The DTR radios are nice, but for practically the same thing, the Trisquare radios are better priced.

Of course in a serious working environment where you are worried about ruggedness or so, perhaps the Motorola radios are better, but seriously, I would consider the TriSquare units.

 

[SCPD]

My wife and I have been using the DTR 650 for a few months and we love them. They're compact, light weight, and almost idiot proof We've only used them when traveling for car to car use and have been able to get 2 miles coverage between us at the most. The "security" of the radios is really nice in that you can create private groups which is almost like having encryption.

 

[N2DLX]

The big difference between the DTR and Trisquare radios is that DTR uses a digital modulation (true digital voice) whereas the Trisquare units are analog voice with FHSS (Frequency Hopping). The digital voice would help out when the analog is getting very noisy and scratchy, and the FEC (Forward Error Correction) helps to correct for missed data bits due to a weak signal. I know the Trisquare units are quite good and beat out an FRS/GMRS radio for most circumstances. But I'd be interested to see a real side-by-side comparison of DTR vs. Trisquare.

 

[tekshogun]

Agreed, of course, we are talking about a nearly 200 dollar difference in radios here. So I can understand Motorola's vocoder technology being a little pricey on top of probably being far more rugged than the Trisquare units. I can see the Motorola vocoder being great for RF-interference but I can see the analog spread-spectrum stuff working better on the fringes of comm. range.

I can not find a side-by-side comparison but for the general public, if we were all using Trisquare, then as setup now, a small city would be able to use these entirely in place of their landline phones and cell phones if the range/line-of-sight issues were overcome, all with out interfering each other. At least, that is the theory. I think I'll be picking up a twin pack of the TSX300 soon. Some one brought them to one of my my ham club meetings and we were impressed. There were even some kids there and they figured out the text-messaging rather quickly.

 

[matt131]

I have tested the Motorola CP200 UHF 4 watts to the Motorola DTR-650 1 watt 900mhz portable and I have gotten better range out of the DTR-650 radios. My conclusion to that is that due to the 900mhz and them being digital is why I would be getting the better range.

 

[RADIOGUY2002]

Hmm

You guys do realize that WDW has 800 and 900 mhz pipe in in various sections of the property. Along with leaky coaxcable in various places. Thats going to make a huge difference in audio and siginal degrations as oppose to uhf and vhf systems. I want a tour of their comm system, or that building that sits on the property line with 400 ft radio towers.

 

[N2DLX]

Forget their 800 MHz transmitters, what about 500 people within 1,000 feet of you with FRS/GMRS radios yakking on them endlessly? I'd take leaky coax from a 50W transmitter 1/4 mile away than several watts being radiated within sight of me.

GMRS would probably work great if there wasn't so much co-channel interference in the parks. WDW's Nextel system is not sharing the same channels as the DTR/Trisquare radios, so even with a noisy transmitter it still won't cause as much interference as an on-channel source.

When I go there next I'd love to tape a VHF radio, UHF radio, and a DTR or Trisquare radio together and try them out under the exact same conditions. I'm sure the results would be interesting.

For the Hams, there are 2M and 440 WDW repeaters on property apparently. If this is true, coverage should be phenomenal, although you're limited to who you can talk to.

 

[tekshogun]

Walt Disney World has its own Amateur Radio Club.

ARRLWeb: ARRL NEWS: Surfin': On the Radio at Disney

 

[matt131]

Response to Rich

Hi Rich, I have tried a 5 watt VHF portable a 4 watt UHF portable and the DTR units all under the same if not similar conditions. The DTR units work better than the UHF or VHF portables. The one example I use is that my family was at EPCOT at Sorin out side and I was in an elevator at the beach club Resort and I was able to talk to them. To me that is amazing coverage with a 1 watt digital radio. Now the conditions may not always be perfect so the radio works all the time but out of all the tests I have done I would stick with the DTR units.

 

[N2DLX]

Hi Rich, I have tried a 5 watt VHF portable a 4 watt UHF portable and the DTR units all under the same if not similar conditions. The DTR units work better than the UHF or VHF portables. The one example I use is that my family was at EPCOT at Sorin out side and I was in an elevator at the beach club Resort and I was able to talk to them. To me that is amazing coverage with a 1 watt digital radio. Now the conditions may not always be perfect so the radio works all the time but out of all the tests I have done I would stick with the DTR units.

Well that makes perfect sense, because the 900 MHz DTR radio would have far better building penetration than VHF or even UHF. Probably the best reason for why 900 MHz reportedly works so well is because when you're actually in a park, you're in a very congested and "urban-like" environment where 900 MHz performs best.

 

[RayAir]

On the last 3 cruises I have been on , I took different radios each time. The first cruise I took a pair of 2W Midland GMRS radios. They worked so-so. The second time I took a pair of 4W UHF Motorola Visar radios. They worked OK, probably about the same as the 2W GMRS. The third time I took a pair of Motorola DTR 550's and they had the best coverage on ship. The coverage was much better than the 4W UHF radios. I have the first generation DTR, the second generation has the longer, removable 900MHz antenna. You can even buy an improved 2.5dbi gain 900MHz antenna for it so the range should be slightly better than the first gen. DTR. They claim 250,000sq.ft. coverage for the first gen. and 300,000sq. ft. coverage for the standard second gen.

I just wish you could disable the Nextel like beeps on the DTR.

I will always take an FRS/GMRS radio along on trips also. FRS was a party line in Las Vegas. Ch. 7 was the unofficial casino-casino channel. I talked pretty good from my room window on the 8th floor of TI.

 

[tekshogun]

The 900MHz ISM radios, with their digital communicatinos and spread spectrum technology will act similar to cell phones. Cell phones with their far less than a watt of power and the virtual disappearence of outboard antennas communicate very well with excellent bandwidth to the towers they are associated with, across distances of miles. Of course these antennas are placed high enough to cover their geological areas, the idea is if cell phones could communicate directly with each other, in a sort of ad-hoc network, they would work great for this as do the Motorola and Trisquare ISM radios. The technology is sound and they all work so great by a combination of things, the nature of 900MHz, digital packets, error checking, frequency hopping spread spectrum, etc; all of these things lead to very efficient communications that become reliable in RF-dirty environments.

 

[matt131]

With all the RF in the parks I am surprised that the FRS radios work. With the remote control, wireless mics, and all the other wireless systems in the park you guys are right there is a lot of interference. I know that many years ago WDW did operate on GMRS radio freqs. The monorails where on 462.575, MK was on 462.625 and EPCOT was on 462.650 and 462.675. Then they went 900 trunk system I think that was the Disney 2000 system and now they are nextel. With this type of company you would think they would have the state of the art comms system. I would think some P-25 digital trunking system myself. Oh well just my opinion.

 

[tekshogun]

Heh, well there is a line between "state of the art" and insanely expensive. Is this Nextel system they're on the usual group talk capable Nextel direct-connect? I am assuming so. If that is the case, they don't have to maintain licenses and equipment and being over the GSM network, the transmissions are digital, so why do you need P-25? They also don't have to worry about people scanning their conversations.

 

[kayn1n32008]

...being over the GSM network, the transmissions are digital...

iDEN TDMA not GSM. Otherwise i would not be an iDEN user as i refuse to deal with the two GSM cellular providers(one owns the other) here in Canada, one has very limited coverage, and makes you pay extra to use the parent company's infrastructure, and the other has very lousy customer service.

 

[RADIOGUY2002]

Testing Ground

They also don't have to worry about people scanning their conversations.

Their is your answer, did you watch the timing changes to when they switch over to certain systems. They also avoid the narrowband requirements on uhf by switching as well. I would assume they have their own internal deicated nextel system, with outsider capabilities for certain people. They seem to be the motorola testing ground on serveral levels.

 

[matt131]

You are right about disney being a testing ground for motorola. They actually used to have a motorola display with radios you could try at Innoventions years ago when FRS first came out.

 

[RADIOGUY2002]

Yeap

Under the Epcot dome, I always love that display. I even wondered if they were connected to any other channels or repeaters. By some how that annyoning beep proved me wrong....