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Jeff Wexler

Zaxcom MicPlexer 2

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 From my initial testing the micplexer II is a lot better then the micplexer I. It has a lot less noise. And the selectable blocks are a no brainer especially for a traveling mixer.

 

 

10298826_10204508682816980_5172692855842

Rado, you have room for one more receiver and a pencil drawer/NP-1 battery.

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 From my initial testing the micplexer II is a lot better then the micplexer I. It has a lot less noise. And the selectable blocks are a no brainer especially for a traveling mixer.

 

 

10298826_10204508682816980_5172692855842

Rado, you have room for one more receiver and a pencil drawer/NP-1 battery.

 

 

 

What is a NP1 pencil drawer?  This?

 

204170.jpg

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if there is a micplexerII question I am happy to chime in...

​I'm interested in buying a Micplexer II for my bag and Shure UR5 receivers.

Have you experienced any extended range using the Micplexer II? Or is the RF signal just more stable?

I'm thinking that the +6dB will lower the squelch on my receivers (which in some situations are a bit too high even in the lowest setting). At the same time, the RF noise is raised 6dB as well.

Of course, having just one pair of antennas will enable me to raise them up in the air or even use directional antennas when needed.

Anyway, any objective and subjective thoughts about the Micplexer II in use, is highly appreciated.

 

Thanks

Fred

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Just got a Micplexer2 myself. Difficult to say whether range is different or more stable using sharkfins, because it's so good anyway, but does seem to have helped with dipole range and stability, but haven't had a chance to do a more controlled test as yet though.

I like the small form factor and filtering, and it runs very cool, which confirms the 0.1w very low power consumption to me, as I've temporarily had it in a neoprene jacket which is good insulation, and would have showed up any heat generation.

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If I was to use the Micplexer 2 with 2 x Bluefin Antenna's I would be getting an additional 11db gain (3db removed for the antenna's being split).

Is that too much additional gain? Or because it's a digital system it shouldn't overload it? Or should I just switch between whips and bluefins depending on the situation?

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It is almost impossible to overload a Zaxcom receiver.  Either way it should be fine. Whips or blue fin. Generaly directional antennas are always the way to go.

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6 minutes ago, glenn said:

It is almost impossible to overload a Zaxcom receiver.  Either way it should be fine. Whips or blue fin. Generaly directional antennas are always the way to go.

 

Thanks Glenn!

Out of curiosity then though why does the PSC RF Multi overload Zax Receivers?

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3 hours ago, sciproductions said:

...

Out of curiosity then though why does the PSC RF Multi overload Zax Receivers?

 

In what situation? Is this something that has been verified, or another case of "internet wisdom"? 

 

I've used Zax receivers with MicPlexer I, MicPlexer II, PSC RF Multi, and Lectrosonics distros all with success and satisfaction. 

 

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1 hour ago, John Blankenship said:

 

In what situation? Is this something that has been verified, or another case of "internet wisdom"? 

 

I've used Zax receivers with MicPlexer I, MicPlexer II, PSC RF Multi, and Lectrosonics distros all with success and satisfaction. 

 

 

I haven't used the PSC RF Multi's, maybe internet wisdom, but I'm fairly sure that Glenn himself confirmed that PSC RF Multi's / any form of active antenna distribution would overload QRX's.

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4 hours ago, sciproductions said:

 

I haven't used the PSC RF Multi's, maybe internet wisdom, but I'm fairly sure that Glenn himself confirmed that PSC RF Multi's / any form of active antenna distribution would overload QRX's.

Lectro distribution systems won't overload receivers as the gain from input to multi-outputs is 0 to 1 dB, i.e., the output of the distribution system is the same as the antenna input itself. RF amplifiers, however,  such as in active antennas or inline amps can have gains of 12 dB or so if not used with splitters or long cable runs. In general, adjust RF gains so that the receiver sees the same RF levels as the antenna itself, within a few decibels. This does not apply to directional antennas and their "gain" as this is a different type of gain, i.e., a gain above the noise floor.

Best Regards,

Larry Fisher

 

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PSC SMA multi does not overload a qrx. It does provide a wideband amp in front of our tunable 35mhz wide front end. Because it has more gain at 460MHz then it does at 550MHz it is a really bad choice to use with our wireless. The intermodulation we work so hard to eliminate is easily mixed within the PSC and can land within our 35MHz wide filter.

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I tested PSC SMA on the field with a the Las Vegas Swat team and every time somebody keyed a Digital walkie next to me there was a giant drop out. Walkies were 470mHz and my lavs were 550-560mhz. Removing the PSC SMA fixed the problem.  

The same goes for MicPlexer. When I removed the 35mHz filter and just used it as a wide band combiner digital walkies were causing drop outs.

I believe it is more to do with a wideband distribution more than amplification.

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23 minutes ago, RadoStefanov said:

I tested PSC SMA on the field with a the Las Vegas Swat team and every time somebody keyed a Digital walkie next to me there was a giant drop out. Walkies were 470mHz and my lavs were 550-560mhz. Removing the PSC SMA fixed the problem.  

The same goes for MicPlexer. When I removed the 35mHz filter and just used it as a wide band combiner digital walkies were causing drop outs.

I believe it is more to do with a wideband distribution more than amplification.

Hi Rado,

It is also the "toughness" of the amplifier in front of the RF splitter in the distribution system. If the amp is a high power design (high 3rd order intercept) then strong out of band signals can be handled with little or no degradation. Think of it this way: A transistor radio running off a 9 Volt battery can't handle high level bass and a flute simultaneously without terrible buzzing sounds modulating the flute. A top notch home stereo can handle both sounds with clarity and little or no degradation of the flute. At least to the point of bleeding ears. If you put a filter in front of the either audio amplifier that filters out the bass, both the weak system and the strong system can reproduce the signal. So you are correct that wide band systems have more overload problems than narrower systems, amplifiers being equal. High power amplifiers will have fewer overload problems given the same bandwidth. Ideally, distribution systems would be narrow band and high power. Narrow band of course means it is harder to operate multiple receivers across the spectrum simultaneously. We would like to have a distribution amp that operates from DC to light, runs off a AA battery and never overloads. Pick zero out of the three.

Speaking of bleeding ears, it is also possible that the early stages in the receiver are being overloaded by the out of band signals, The 35 MHz filter could prevent that also.

Best Regards,

Larry Fisher

p.s. Not trying to insult the RF experts but some other readers may understand the above audio analogy more easily. 

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13 minutes ago, sciproductions said:

 

I was referring to this previous comment from Glenn on facebook

Screen Shot 2020-04-21 at 2.39.45 pm.png

 

You made my point -- his post has nothing to do with the signal from the transmitter overloading a receiver, Glenn was referring to the use of a bandpass filter in order to prevent interference from walkie talkies. 

 

 

 

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1 hour ago, John Blankenship said:

 

You made my point -- his post has nothing to do with the signal from the transmitter overloading a receiver, Glenn was referring to the use of a bandpass filter in order to prevent interference from walkie talkies. 

 

 

 

 

Sorry about that, you are correct.

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On 4/20/2020 at 5:27 PM, LarryF said:

Hi Rado,

It is also the "toughness" of the amplifier in front of the RF splitter in the distribution system. If the amp is a high power design (high 3rd order intercept) then strong out of band signals can be handled with little or no degradation. Think of it this way: A transistor radio running off a 9 Volt battery can't handle high level bass and a flute simultaneously without terrible buzzing sounds modulating the flute. A top notch home stereo can handle both sounds with clarity and little or no degradation of the flute. At least to the point of bleeding ears. If you put a filter in front of the either audio amplifier that filters out the bass, both the weak system and the strong system can reproduce the signal. So you are correct that wide band systems have more overload problems than narrower systems, amplifiers being equal. High power amplifiers will have fewer overload problems given the same bandwidth. Ideally, distribution systems would be narrow band and high power. Narrow band of course means it is harder to operate multiple receivers across the spectrum simultaneously. We would like to have a distribution amp that operates from DC to light, runs off a AA battery and never overloads. Pick zero out of the three.

Speaking of bleeding ears, it is also possible that the early stages in the receiver are being overloaded by the out of band signals, The 35 MHz filter could prevent that also.

Best Regards,

Larry Fisher

p.s. Not trying to insult the RF experts but some other readers may understand the above audio analogy more easily. 

Thanks Larry,

great analogy.
btw It’s not harder to operate multiple receivers over the spectrum with pure digital RF. But you guys know that now. 

(; 

 

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