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RF Dropouts


nevo
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Hi I have just done first week on a feature and have run into a problem particularly with one of our actors......This a radio mic heavy, wide n tight 2 camera shoot.

Im getting constant hits on our lead actress mic.

The wardrobe is problematic in that it’s very tight fitting dresses and crop tops and tons of jewellery......

I’m using SM type TX and have tried different units ,different  Power options .... placement of the Tx is limited.

im running 8 radios plus two booms all lectro SMA SMV SMQV and am not really having problems with any of the other cast.

The recievers are venue 1 and when I need to I’m running Shure active antenna with 40ft and 100 ft runs with LMR240uf

With this actor I have the TX sewn into the back of her crop top.

Sometimes I’m only getting 30 ft then the signal dips and I get small pfffst.....

I be run out of ideas.

Sometimes I’m getting normal range with her and as I said the other actors range seems ok.

The only thing I can think of is the metal in the necklaces is the culprit.

Any thoughts appreciated

Nevo

The other rf killer is the 1 foot thick stone walls in the castle we are filming in but I can usually get some line of sight

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There are many possible causes for the dropouts you are experiencing. I think your hunches are probably right but harnessing that insight to a solution is difficult. (But others may contribute good suggestions.)

 

I can tell you that my experience has been that momentary hits are often easily corrected. That "pfftt" sound is loud but usually very brief. It does require work by the assistant editor to sliver the hits out but it can often be accomplished seamlessly and without excessive difficulty. Usually fixable, if that helps.

 

Of course, occasions where the signal drops out for whole words is another magnitude of trouble.

 

David 

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1 hour ago, nevo said:

 

The only thing I can think of is the metal in the necklaces is the culprit.

Any thoughts appreciated

Nevo

The other rf killer is the 1 foot thick stone walls in the castle we are filming in but I can usually get some line of sight

 

Apologies in advance if my suggestions sound silly!

 

Is the antenna pointing upwards? If it gets too close to the metal necklaces I would try pointing it downwards instead. 

 

As for stone walls, what about hiding an antenna and running some cable? You can build a radome with some RF inert material. Even simple paper (there is paper available imitating stone textures) covering the antenna should work. 

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Thanks for the suggestions 
I’ll do some tests in blocking and rehearsals without the portable faraday cage (necklaces)she is wearing around her neck and share the results

46 minutes ago, David Waelder said:

There are many possible causes for the dropouts you are experiencing. I think your hunches are probably right but harnessing that insight to a solution is difficult. (But others may contribute good suggestions.)

 

I can tell you that my experience has been that momentary hits are often easily corrected. That "pfftt" sound is loud but usually very brief. It does require work by the assistant editor to sliver the hits out but it can often be accomplished seamlessly and without excessive difficulty. Usually fixable, if that helps.

 

Of course, occasions where the signal drops out for whole words is another magnitude of trouble.

 

David 

Hi David

So far the hits have been quite low and I think we will get away with clean up in post

The boomS  have  Been sounding useable, but the stress levels do go up when your not getting solid RF

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I forgot: An easy source for radome  material can be aquarium stores. They use to stock stuff for making aquarium backgrounds. I remember some of it was thick paper with a rock like texture. It would probably pass. 

 

 

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I‘m sure you are scanning for frequencies beforehand and tried different frequencies?

If due to the tight dress the tx antenna is touching her body, you could try to get it away with a hush lav or something else. 
Also try another block... 

if it’s really killing you and you can trace it to the necklace, you could ask wardrobe/props/production to produce a plastic replica. They will probably only consider it - if at all - if you can’t get any useable audio. 
 

I had an actress once where nothing worked. 10 feet on a regular basis. Everyone else was fine. Sometimes this can happen, but it is annoying. 

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3 hours ago, Constantin said:

I had an actress once where nothing worked. 10 feet on a regular basis. Everyone else was fine. Sometimes this can happen, but it is annoying.

I have had this happen as well, on a couple occasions. Tried different (coordinated) frequencies, different transmitter, block, make sure they don’t have their phone in their pocket etc - still  just the one actor had RF problems...  to this day, I don’t know why. And yes, I have hush-lavs on the antennas. 
I understand my comments won’t help finding a solution here, but it seems like this can happen for whatever reason with some people. Yep - it’s probably voodoo.

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28 minutes ago, Johnny Karlsson said:

Yep - it’s probably voodoo.


The director on the production where I had this happen, said she wasn’t surprised at all, because this particular actress was radiating this special energy. Still not 100% exactly sure what she meant, but it’s as good an explanation as any

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Thanks for all the replies and yes the antenna has a hush lav on it ...I’ve tried different frequencies And blocks and I’ve  coordinated my frequencies.

Im thinking she may be a witch only logical explanation 

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Voodoo or not, I like the radiance explanation. 
I once worked on a doc were the one particular person was always causing problems with the digital wireless. 
Always prepped and tried everything to make sure it was working 100% before he showed up. More often than not I had distorted signal and significant decrease in range. 

I never could pin down what caused it, but I found that an analog spare set that I had did the job. 

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2 hours ago, Constantin said:


The director on the production where I had this happen, said she wasn’t surprised at all, because this particular actress was radiating this special energy. Still not 100% exactly sure what she meant, but it’s as good an explanation as any

 

35 minutes ago, Lucas said:

Voodoo or not, I like the radiance explanation. 
I once worked on a doc were the one particular person was always causing problems with the digital wireless. 
Always prepped and tried everything to make sure it was working 100% before he showed up. More often than not I had distorted signal and significant decrease in range. 

I never could pin down what caused it, but I found that an analog spare set that I had did the job. 

 

I have a relative who says he's never been able to wear a "digital" watch, because he "puts out too much electricity". 

 

And I think we've all been in situations where voodoo was just about the only "reasonable" explanation...

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2 hours ago, nevo said:

Thanks for all the replies and yes the antenna has a hush lav on it ...I’ve tried different frequencies And blocks and I’ve  coordinated my frequencies.

Im thinking she may be a witch only logical explanation 

Does she look like this?

 

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11 hours ago, PMC said:

Does she look like this?

 

 

You can hide a lav, transmitter and antenna inside that promising radome!

 

Even pros (and I mean two friends who are actual experts on RF, one of them worked for Agilent in Santa Rosa and they are university professors) say that RF can be a bit of voodoo now and then.

 

Now, seriously. No metal in the clothing? I mean, a bodice with some metal wires or something similar? Something must be detuning the antenna. Maybe she is sweating a lot and adding some isolating material between the antenna and the clothes might help?

 

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