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I'm not sure which thread to post this in, so I'll drop it here.

 

 

A buddy of mine and I did a range test today using the following gear:

Sennheiser G3
Zaxcom TRK900LA / QRX100
Lectrosonics SM / UCR411A
Comtek 216 series
Zaxcom ERX2TCD

I understand that there's a lot of variables to doing a test such as this, but we had a lot of fun doing it, we just wanted to test our gear, and to just get a general idea on how the range was since we have never found a solid answer.. Keep in mind, this was all LOS (Line of sight) testing. All results are based on when there was a complete dropout in signal. Each test had spotty results about 30-50ft before dropout.

We didn't have a way of tracking distance, so I used this site to figure it out afterwards. I'm confident that these numbers are correct. This is why we used landmarks to measure later.
http://www.daftlogic.com/projects-go...calculator.htm

We set everything we could to the same (or close) frequencies for the best results with what we had.

We used a Zaxcom Nomad for the test.

I strapped on all of the wires and IFBs and started walking. We did this same test for every piece of gear, running an IFB and a wire at the same time for communication.
The results surprised us both.

Starting with the Lectro, we got roughly 470ft. This was impressive since we were using only the ENG style rig with no fins. We didn't have the SMV, so I believe the output power was default 50mw, which was still great.

Sennheiser G3, I believe, has an even lower mw output, but nearly got the same range. it was about 100ft shorter before cutting out. Not bad, but the sudden loud hisses were a little annoying.

Zaxcom TRX900LAs set to 50mw went about 3/4 the distance as the lectro did until we bumped up the power to 125. Then it reached about where the SM went (470ft). It was still spotty. We were also still able to send commands to the transmitter via zaxnet, including the recording ability, but this could only be done when we were moved a bit closer (roughly 360ft).
We also set the QRX back and forth from Dual to Single. It really didn't seem to add to the range much though.

The Zaxcom ERX2TCD and the Comteks were an easy test. The ERX went almost 500ft before giving out. Sure, there were a few dropouts on the way, but overall it still sounded very good. Almost as if I were listening to the recorder itself. The Comtek didn't even go half the distance before hissing at us and making noises. The ERX was crystal clear the entire way, while the comtek sounded angry almost the entire time.

Now here's the fun part. Since we both own a nomad, we wanted to try something neat. Using Zaxnet, we paired our nomads together (him transmitting and me receiving) so that he could send me audio signal from his to mine via the built in IFB. He kept the QRX and I took the TRX and a nomad with me. I was monitoring his receiver from his bag, in my headphones from my bag. This was very cool. I got a little farther than the ERX before dropping out. A little over 500ft. Of course, I couldn't hear the TRX anymore, but I could hear his slate mic when he would talk to me. This seems like a fun way to chat with other fellow zaxcom users on multi mixer ENG shoots. Haha

They all had range far better than we were expecting, other than the comtek. I do believe that all of the gear reached more than enough distance for what they'd be used for. Especially in an ENG setup. Of course, if we had fins, the distance would have multiplied, I'm sure. I wish we could have had the lectro IFB with us, but I'm thinking it would have been around the SM, which was very good.

Again, this was just a fun thing we wanted to do and the results came out surprising for us both. They'd be different for everyone, but now we have a general idea of what they're capable of.

If there's anything anyone notices that we could have done better or something we can try next time, please let me know. I'd love to do it again with any new advice or settings. Also, any questions are welcome. I may have missed a few things. Our test was pretty extensive.

- Sessoms

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Hey, it's not a problem. I appreciate the info. I hadn't looked it up yet, and that's all good to know. I understand the different forms of communication between gear. Regardless of what each is using, it was a general range test for the gear that we have.

 

More elaborate tests can and should definitely be done if they haven't already.

 

Thanks again for your input!   :)

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I stopped by while John was doing his test, was very unique seeing someone with 5 different transmitters/lavs strapped to them.

 

Good work, John!

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A very good contribution to the forum. And very enterprising.

 

This is also a good opportunity for me to plug the range tests I made for the 695 Quarterly. I didn't test transmitter-receiver sets; I confined my tests to various antenna systems. But the methodology was very similar. I did employ one refinement you might consider if you make further tests: I mounted the transmitters to a short pole that the "walker" would carry at waist height. This removes - well, substantially reduces - the absorption effect of having the transmitters mounted on a person.

 

The Quarterly issues with the tests are available on the 695 site:

http://695quarterly.com/

 

Portions of the 695 site are exclusive for members but the journals are available to anyone.

 

Back issues are here:

http://695quarterly.com/previous-issues/

 

The antenna tests start with the Spring 2010 issue and continue through Summer 2011.

 

One of the general conclusions one could take from these tests is that no single advantage would yield an extraordinary improvement. Using high gain antennas or a more advantageous antenna position might produce a range improvement of about 20% but nothing doubled the range. This was also true when using storied antennas like the PSW Helical or the Sennheiser Circular Polarized antennas. Nothing produced a reliable improvement over ordinary whips of more than about 20% or, maybe 25% or so when multiple advantages were added together. But better antennas or more output power did yield reliable (if less than dramatic) improvements.

 

David

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Good for you for doing your own tests with your own gear in your own town.  Very valuable info

 

philp

 

Thanks philip. We definitely enjoyed doing this!

 

I stopped by while John was doing his test, was very unique seeing someone with 5 different transmitters/lavs strapped to them.

 

Good work, John!

 

Haha, it was quite the site huh? I actually have a photo of me all geared up.

 

Thanks for doing a very thoughtful test. I think I learned a few things as well.

 

Glenn

Thanks Glenn, that means a lot. I'm glad we were able to help! :)

 

A very good contribution to the forum. And very enterprising.

 

This is also a good opportunity for me to plug the range tests I made for the 695 Quarterly. I didn't test transmitter-receiver sets; I confined my tests to various antenna systems. But the methodology was very similar. I did employ one refinement you might consider if you make further tests: I mounted the transmitters to a short pole that the "walker" would carry at waist height. This removes - well, substantially reduces - the absorption effect of having the transmitters mounted on a person.

 

Thanks for the info David. This is a great addition for this thread. Very helpful info.

 

We did tests strapped onto us because when we work, we never see the pack. It's always strapped to talent. We wanted to replicate that the best we could. I also held the gear during the test to see if anything changed. It helped, but not much.

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Another thing I forgot to mention. This is also why I love Zaxcom so much...

 

A point that was brought up during the test, that you all know already, is that Zaxcom, essentially, has infinite range. As long as you're in range when you start recording and those packs start recording, you can go to the moon and back and have all of your dialog clean. Of course you'll need proper mic placement, a big sd card, and a really long lasting battery...but you get the point.  Haha

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One measure that I'd like to suggest: how do each of the transmitters do under suboptimal frequency conditions? It's one thing to see how sensitive a receiver is, it's another thing to tell how robust a TX/RX system is when in a wireless jungle. I know you have already spent plenty of time on the tests, but if you can run the same tests on dirtier channels (I assume you picked clean channels for the initial test), I think that that would be valuable as well.

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You're right. Having some other busy channels to collide with is a great test. I must say though, we weren't in the best of locations either. We did our tests at a local university and it's probably one of the biggest hot spots for freq traffic. It's a tech school and there's a lot going on.

 

Yes, we did find the best frequencies on the blocks. I think doing a test with the best and the worst is something we'll try next.

 

Thanks for the suggestion.

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"I think non diversity like g3 will be more short..."

-- FWIW, the G3 EK100 portable receiver is diversity (adaptive), the 'secondary' antenna is the output cable. The G2 EK100 is non-diversity.

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And diversity has nothing to do with range. Although it should help in a crowded environment

If you are dealing with polarity issues range a horizontal/vertical diversity could enhance range.

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" But is it really the diversity that's the helping factor? Or is it the polarization of each antenna? "

even if it is the polarization, it takes diversity to have multiple antennae (sic)

" And diversity has nothing to do with range. "

thus I would not say this, though diversity is less about extending range than about reliability at the range available

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" But is it really the diversity that's the helping factor? Or is it the polarization of each antenna? "

even if it is the polarization, it takes diversity to have multiple antennae (sic)

Well yes, but as I understand it (and there's a very real possibility that I'm misunderstanding something here), the tx antenna is usually only polarized vertically or horizontally and thus only the corresponding antenna on the rx is needed, so just one

diversity is less about extending range than about reliability at the range available

Exactly, so diversity is not about extending range. In perfect rf conditions a non-diversity and a true diversity system would have the same range. Before this discussion carries on for too long, I think this time it's me who's being slightly nit-picky. I'll stop now

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IF......your were receiving signals with changing polarity having a vertical/horizontal diversity would most likely extend your range.

Having a pair of identical antennas of the same polarity next to each other is questionable.

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Having a pair of identical antennas of the same polarity next to each other is questionable.

But isn't that how almost all systems are set-up?

Sure if the polarity changes, but why would it?

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But isn't that how almost all systems are set-up?

Sure if the polarity changes, but why would it?

 

Yes, but having options to connect a different antennas or have a different polarity are good.

 

RF bounces off objects and talent is not always in a upright position.

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But isn't that how almost all systems are set-up?

Sure if the polarity changes, but why would it?

Yes, but having options to connect a different antennas or have a different polarity are good.

RF bounces off objects and talent is not always in a upright position.

That's both true. Plus I think that the diversity helps with the bouncing by identifying the primary wave and ignoring reflections. I'm not arguing against diversity systems anyway, just talking about range...

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" there's a very real possibility that I'm misunderstanding something here), "

yes, I believe you are misunderstanding ...

 

" RF bounces off objects and talent is not always in a upright position. "

thus polarity ( actually wave orientation ) is all over the place at the RX.

" Having a pair of identical antennas of the same polarity next to each other is questionable. "

very questionable...

" But isn't that how almost all systems are set-up? "

but very convenient ... and easy...

" just talking about range. "

and antennae (sic) are primo important for range...

 

" diversity helps with the bouncing by identifying the primary wave and ignoring reflections. "

more misunderstanding.

Lectro (and other manufacturers) have excellent wireless guides on their websites.

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Actualky no mis-understanding on the first part. If you think so, Senator, please clarify.

But possibly on the second part. Nonethless, my initial remark still holds true

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