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First experience with Zaxcom qrx200 wide band RX


RadoStefanov

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ALL TEST WITH WHIP ANTENNAS SIZE BLOCK 22 AND FREQUENCIES SET BLOCK 25

 

 

I just received a zaxcom qrx200 RX.

It seams a little heavier then qrx200. Buttons feel better. Fitted fine in my qrx holder. 

I installed and fired it on. It has the same menu as qrx100 with added block selection option. I set it up to block 25 and started a scan. Scan is a lot slower. Maybe a little faster then lectro but slower then qrx100q. It does not make any difference to me since I never scan. I just scroll through the freqs and find a clean one. The lack of heavy intermodulation with digital signals allows me to just select random clean frequencies. 

As far as sound I used AES and did not find to sound any different then qrx100. The signal goes and stays  digital from the TRX900LA to the AES out on the qrx200.

I put the TX in my production office in a corner behind a metal door all the way down on the floor. I started walking cross the parking lot that was blocked with huge tour busses and started entering different buildings.Went behind 1' inch metal doors, inside old steel cars and at some found myself approximately 230 feet away going trough busses walls and people in between. 

I realized I am not recording and my TX only works at 50mW.

I decided to switch to DUAL mode and the signal disappeared completely. Walking back the signal was completely gone... I had to walk all the way next to the TX to get a little signal.

The biggest selling point of the qrx200 was not the wide band but the advertised good performance in dual mode on par with single mode. 

I started thinking that it is some kind of bug and a feeling of disappointment was taking over me.

Then I noticed that the first frequency is set to 638.1 and the second to 512.0.

In order to get great performance in dual mode the 2 frequencies have to be set within 35mhz space.

I set the second frequency at 643.0 and the signal immediately improved.

I walked the same route as before in dual mode and found the RF performance to be very similar.

 

I ordered only one qrx200 to test if what zaxcom claims was true. 

I still need real world field test but so far I am SOLD.

Will report more next week especially considering all the driving shots I have to do.

I hope I can just mic the driver on the belt  and not have to worry about micing the car with a remote antenna. This will save me a lot of time and reduce my crucial work flow.

 

THE WIDE BAND IS JUST SO COOL. I dont have to buy a separate block for my Hop when I go out with 2 receivers and my max. I can just use my third receiver.

​I wish ZAXCOM can put a TC out put on the qrx200 even without qifb since the TC is being carried by the sound modulation. 

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Would it make sense to have the whips the length of block 20 so you can drop frequencies lower? Thank you for the review thus far! You made no comparison to the the QRX100 in it's new modulation update nor did you compare it to it's closest competitors answer the SRb. I know your testing is no where complete, just wondering at your firsthand experience and generalization. Exciting developments.

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I am comparing it in my mind to what I get with qrx100 in the same locations. I leave the side by side real world testing for next week when I have to use qrx100 and qrx200 side by side for work.

 

Honestly I have no interest in testing Lectro wireless. I am way beyond  using Lectro ever again..." unless I somehow end up on a show where I have to match other people wireless"

But if enough people insist I have a SRb with 2 LMa block 21 that I can use. The problem is  my friend has been using them for the last year. I can see when he is off and can do some side by side comparasing. But dont count on it to happen any time soon.

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I am comparing it in my mind to what I get with qrx100 in the same locations. I leave the side by side real world testing for next week when I have to use qrx100 and qrx200 side by side for work.

 

Honestly I have no interest in testing Lectro wireless. I am way beyond  using Lectro ever again..." unless I somehow end up on a show where I have to match other people wireless"

But if enough people insist I have a SRb with 2 LMa block 21 that I can use. The problem is  my friend has been using them for the last year. I can see when he is off and can do some side by side comparasing. But dont count on it to happen any time soon.

Excellent thanks Rado, you didn't really make a point by point comparison between the old and new though, you mentioned some of the range but didn't mention whether the QRX100 could do the same (with new modulation) as what you were saying with the QRX200, or maybe it wasn't enough of a range difference with you that you felt the main pull was the frequency upgrades...? It is funny I ran across your postings in like 2011 about your hesitancy to drop your lectros, very interesting to see your turn around!

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Tim, Today is my day off. I wrapped late last night so I could not pick up my qrx200 package. I went in on my day off to pick it up and do a quick test.

Believe since I only have one QRX200 I will be doing 5 days of mixing QRX200 and QRX100 together.

And BTW for the limited amount of testing the range is a lot better.

Will report again next week...

 

As far as hesitancy to drop lectro - It happened in the summer of 2012. Zaxcom proved themselves that their products are in many ways better and the reliability - top notch. Before the qrx200 the only thing they lacked was range compared to 411s. At this point I am almost sure this is not the case. Need to test more in field next week.

And if dual mode works the way I think it does It will really be amazing .

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Tim, Today is my day off. I wrapped late last night so I could not pick up my qrx200 package. I went in on my day off to pick it up and do a quick test.

Believe since I only have one QRX200 I will be doing 5 days of mixing QRX200 and QRX100 together.

And BTW for the limited amount of testing the range is a lot better.

Will report again next week...

 

As far as hesitancy to drop lectro - It happened in the summer of 2012. Zaxcom proved themselves that their products are in many ways better and the reliability - top notch. Before the qrx200 the only thing they lacked was range compared to 411s. At this point I am almost sure this is not the case. Need to test more in field next week.

And if dual mode works the way I think it does It will really be amazing .

These are my thoughts exactly, and I didn't mean to offend, just your initial response in what I highlighted is basically what I assumed/wanted your thoughts on. Your the man now dawg.

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I just would like to ask: what if you'd want to use sharfins having both QRX100 and 200 together, so using different frequency blocks? Same for power distro. In other words, is there something like a broadband MicPlexer to be released? Or we just have to use the receivers with whip antennas only?

ps. I'm not considering the PSC RF Multi just to stay in the Zaxcom domain only.

 

Thanks, v.

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No, Constantin.

 

What I wanted to say was that in my argumentation I was only considering Zaxcom products.

I guess (since I don't own one) that the PSC RF Multi could suit perfectly these needs, just was asking if Zaxcom thouhgt something to menage a antennas/power/ampli distro (like the MicPlexer now do) for multiple frequency blocks. 

 

 

Why not the RF Multi? Any particular reason?

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The RF Multi is not an option for Zaxcom wireless. If you put a wide band amp in front of the QRX200 you will ruin the performance of the receiver and its tunable filter. The multi also has too much gain and xtalk to be used with our receivers.

 

Glenn

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all the more reason to provide a solution that works with the QRX200.

 

curious that you mention the gain of the RF multi, as the micplexer has 9 db of gain (though not sure if that figure includes the loss from the splitter, so it may be only 4 or 5db overall) whereas the RF multi has about 1db of gain overall.

 

i have seen the crosstalk demonstrated on the bench to me, and was shown that not using adjacent SMA connectors helps alleviate this a little.  

 

though i do remember conversations i have had with an rf engineer who was telling me of a system they were developing with digitally controlled filters, and am thinking that something like that with something like the micplexer that was controlled by the QRX200 to set its filters would be an interesting idea. though i say that with no thought to the practicalities of making something like that work.

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Then I noticed that the first frequency is set to 638.1 and the second to 512.0.

In order to get great performance in dual mode the 2 frequencies have to be set within 35mhz space.

I set the second frequency at 643.0 and the signal immediately improved.

 

- Why this?

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the qrx200 has an front end filter that is 35MHz wide. 

so you can have a maximum of 35MHz between frequency 1 and frequency 2.

Jack Norflus laid it out pretty nicely in this post: 

 

I do wonder if the QRX200 will cross blocks as Jack mentioned. From Rado's post it sounds like you select a block in the software options.

 

Mark O.

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apologies if i am slightly wrong with this, but i understood that it was a movable 35MHz filter, not constrained by blocks.

 

but there is the option whilst scanning to only scan through specific blocks or parts of the range available to speed up the scan time or at least make it more useful if you still have your transmitters on specific blocks.

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The QRX200  has a continuous tuning range for maximum flexibility. We will be limiting the frequency difference between the 2 receivers so that they are within 35 MHz of each other. The QRX200 always tunes the filter for the center between the 2 receiver frequencies. If it is more than 35 MHz apart then the performance of both receivers will be degraded.

 

 

Glenn

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I do wonder if the QRX200 will cross blocks as Jack mentioned. From Rado's post it sounds like you select a block in the software options.

 

 

 

Its an option in the receiver to scan specific blocks - so if you are working in a specific frequency range you can just scan what you like.

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