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Michael McQueen

Nomad RF block 21 and 24

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THe SRa is great receiver

When used with 552 it gives me the same range/stability as 411a.

And before when the 552 was in my bag the SRa was my RX of choice for power and weight saving.

Sometimes the real world and the theoretical world coincide and sometime they collide.

The UCR411a has a tracking front end -- The SRa doesn't.

BTW John the front tracking does not help with the nomad spray...

Correct me if I'm wrong guys. But the SRa's are not true diversity right? They only have one antenna per receiver.

Is it possible that might be part of the problem?

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Thanks Larry.

The spray from the Nomad is constant and fast pulsating 1 to 3 and some places 1-5 pixels.

One pixel is roughly a 50% reduction in range. Three pixels will reduce the range another 50%. These are all rough numbers. Ymmv.

Best

Larry F

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I FOUND SOMETHING VERY INTERESTING...

The nomad has way less spray from the back.

I put it in the front of the bag and the spray was greatly reduced...

By the back do you mean the side opposite of where the input connectors are?

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Since the outer case of the Nomad is plated it is non conductive. It would be possible to remove the plating from the inside of the outer case cover to reduce the RF emitted. I would use a dremel tool with a sanding wheel to do it. If anyone wants to try it, it only should be done around the screw holes only so that there is an electrical connecton when the screw is tightened.

This could reduce any RF emission from Nomad. It is not anything I have tried but it might have a good result.

The emission from Nomad is very low and is lower than other similar products but there is always room for improvment. With some of the BAG pictures I have seen it would be a big benefit to not have receivers within 2 inches of the Nomad case. A spacer between them would be a big help.

Glenn

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A spacer helps in all recorder/RX combos re RF spray, but we are at cross-purposes here. Moving the load in a bag outward even by a small amount greatly increases the load one feels wearing it. In general sound-baggers try to make the bag as compact front-to-back as possible.

phil p

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In my case taking RXs outside makes everything worst.

By the way I do not have the internal AAs in my unit for reasons I do not want to share, and when I put the AAs in I notice a little less spray.

A spacer helps in all recorder/RX combos re RF spray, but we are at cross-purposes here. Moving the load in a bag outward even by a small amount greatly increases the load one feels wearing it. In general sound-baggers try to make the bag as compact front-to-back as possible.

phil p

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Not bottom....

Back.

WHen you look down at your SOUND BAG direction.

Didn't mean the bottom, I meant the side that is closest to you as you're looking down at the bag. Then the opposite side would be where the input connectors are. Just different opinions of what is considered the front and what is considered the back.

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Then the opposite site of the input connection I guess.

Didn't mean the bottom, I meant the side that is closest to you as you're looking down at the bag. Then the opposite side would be where the input connectors are. Just different opinions of what is considered the front and what is considered the back.

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Didn't mean the bottom, I meant the side that is closest to you as you're looking down at the bag. Then the opposite side would be where the input connectors are. Just different opinions of what is considered the front and what is considered the back.

Wouldn't the descriptive "top" and "bottom" for the unit be the clearest way to describe? Forget how it is oriented IN the bag when referring to the surfaces of the unit itself. When just sitting on a table, the TOP is the top surface, the BOTTOM is, well, the bottom surface it is sitting on. Then you have the left side and the right side, the front (where the controls are) and the back. Done.

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Wouldn't the descriptive "top" and "bottom" for the unit be the clearest way to describe? Forget how it is oriented IN the bag when referring to the surfaces of the unit itself. When just sitting on a table, the TOP is the top surface, the BOTTOM is, well, the bottom surface it is sitting on. Then you have the left side and the right side, the front (where the controls are) and the back. Done.

What you said! I was thinking of the orientation as it's sitting in the bag, not as you described sitting on a table. Makes sense.

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Wouldn't the descriptive "top" and "bottom" for the unit be the clearest way to describe? Forget how it is oriented IN the bag when referring to the surfaces of the unit itself. When just sitting on a table, the TOP is the top surface, the BOTTOM is, well, the bottom surface it is sitting on. Then you have the left side and the right side, the front (where the controls are) and the back. Done.

Agreed. That's how I see it, too.

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" If I choose a free frequency after the first scan it starts having 3 bars RF 10 second after. "

that sounds like "intermodulation"

" But the SRa's are not true diversity right? "

they offer two different true diversity implementations...

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" If I choose a free frequency after the first scan it starts having 3 bars RF 10 second after. "

that sounds like "intermodulation"

intermodulation from the NOMAD RF. It is all over the spectrum.

With the Nomad off there is nothing.

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I did some side by side RF scans today with a block 21 UCR411 and a block 25 UCR401 comparing RF spray from a 552, a 744t, and a Nomad. Here are the photos:

First with the whole system running on a NP1

post-2639-0-51276400-1330903668.jpg

Then with the whole system on internal batteries:

post-2639-0-13530300-1330903719.jpg

And control:

post-2639-0-09434300-1330906283.jpg

I'm considering ordering some cobaltex and incorporating it into my bag to see if this improves.

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In my experience physical separation between 744t and RX almost eliminated the rf spray.

With Nomad physical separation does not help.

But one thing I notice is if I put 2 411s one behind the other, the second one "further away from the Nomad" has less spray.

If I put a 552 between the Nomad and the RX it does not act the same.

Strange.

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I did some side by side RF scans today with a block 21 UCR411 and a block 25 UCR401 comparing RF spray from a 552, a 744t, and a Nomad. Here are the photos:

Do you have a control photo - just a scan with all the recorders off?

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I just received my Cobaltex, and did some updated scans. It seems like the fabric helps a bit, but doesn't get rid of it completely. I lined the recorder pocket with a layer, and also lined the receiver pocket with a layer. As Glenn mentioned Zaxcom does have a fix for RF spray coming from the power plug. I'm sending my unit back to get the update. Let's hope it takes care of it.

Nomad powered off:

post-2639-0-77489800-1332803127.jpg

Nomad powered on, no Cobaltex:

post-2639-0-59666800-1332803165.jpg

Nomad powered on, with Cobaltex:

post-2639-0-31986400-1332803198.jpg

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Here's my scans for today on blocks 21 and 24. SRas and Nomad powered off one Hawk Woods NP1 distro. IFB off though it doesn't seem to make much of a difference. Scan results vary a little depending on where I position the receivers.

Nomad on (left is block 21, right block 24)

scannomad1.JPG

Nomad off:

scannomad2.JPG

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