FRS Radio causing scanner interference

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slicerwizard

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N_Jay said:
You are still missing the point.
I feel your pain. Despite his iDEN training, lemish is 100% wrong. His "it has more to do with the fact its a transmitter thats always transmitting" claim is clearly not true; Nearby continuous carriers produce receiver symptoms like mild desense (increased static levels) or major desense (target signal completely lost), but it's the pulsed signals (like iDEN) that cause the noisy symptoms that mikeydcg2003 brought up with his "Nextel's are the worst for interference" comment. These symptoms are even seen at power levels that would be too low to cause problems if the carrier were continuous.
 

kb2vxa

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Hi X and all,

Now you've gone and one it, ask a simple question and before long they start discussing nuclear physics. OK, back to the beginning with a simple answer that should clear up the confusion.

"Scanners typically have poor selectivity."

Great Lakes means "front end" selectivity which for all practical purposes is absolutely nil. The RF amp is so broad it receives "DC to light", that is everything at once and the selectivity comes in later, primarily in the last IF amplifier chain.

It's the RF amp being overloaded to the point of cut-off that's causing the "blackout" of signals, an extreme case of "desense" or de-sensitization. When the transmitter is farther away the condition is reduced so signals are received but at a much lower than normal level.

Now if you want to REALLY confuse people you may discuss transistor beta, operational curves and amplifier bias. Solid state engineering theory you >need< to understand what's going on inside the box. In other words you must learn Greek to impress like a geek, better yet use scientific font in your posts and fill them with advanced mathematics. (;->)

I hope you have learned your lesson, when you ask the time some will tell you how to build a cesium ion laser atomic clock.
 
A

ACU1000

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slicerwizard said:
I feel your pain. Despite his iDEN training, lemish is 100% wrong. His "it has more to do with the fact its a transmitter thats always transmitting" claim is clearly not true; Nearby continuous carriers produce receiver symptoms like mild desense (increased static levels) or major desense (target signal completely lost), but it's the pulsed signals (like iDEN) that cause the noisy symptoms that mikeydcg2003 brought up with his "Nextel's are the worst for interference" comment. These symptoms are even seen at power levels that would be too low to cause problems if the carrier were continuous.


kbtvxa is right - the original question could be answered in the terms of desense... and everyone took my responses and twisted them into something more than the original question implied. Regardless of how much iDEN training I may or may not have, you people are typical posters and flamers who have added nothing to helping get the original question answered.
 
N

N_Jay

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slicerwizard said:
I feel your pain. Despite his iDEN training, lemish is 100% wrong. His "it has more to do with the fact its a transmitter thats always transmitting" claim is clearly not true; Nearby continuous carriers produce receiver symptoms like mild desense (increased static levels) or major desense (target signal completely lost), but it's the pulsed signals (like iDEN) that cause the noisy symptoms that mikeydcg2003 brought up with his "Nextel's are the worst for interference" comment. These symptoms are even seen at power levels that would be too low to cause problems if the carrier were continuous.


Ahhhhhh. . . . . . .

Thanks!!:wink:
 
N

N_Jay

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lemish said:
kbtvxa is right - the original question could be answered in the terms of desense... and everyone took my responses and twisted them into something more than the original question implied. Regardless of how much iDEN training I may or may not have, you people are typical posters and flamers who have added nothing to helping get the original question answered.
'

1) your original post was well after the original question was answered.
2) you tried to answer a second issue brought up as an off-hand comment by some one.
3) your answer to the off-hand comment was INCORRECT and CONFUSING.
4) you have resisted all attempt to correct and clarify your misunderstanding of the issue.

AND

5) now, you have the audacity to say; "you people are typical posters and flamers who have added nothing to helping get the original question answered."

Hello!!!!!:evil: :evil: :evil:
 

xpawel15x

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kb2vxa said:
Hi X and all,

Now you've gone and one it, ask a simple question and before long they start discussing nuclear physics. OK, back to the beginning with a simple answer that should clear up the confusion.

"Scanners typically have poor selectivity."

Great Lakes means "front end" selectivity which for all practical purposes is absolutely nil. The RF amp is so broad it receives "DC to light", that is everything at once and the selectivity comes in later, primarily in the last IF amplifier chain.

It's the RF amp being overloaded to the point of cut-off that's causing the "blackout" of signals, an extreme case of "desense" or de-sensitization. When the transmitter is farther away the condition is reduced so signals are received but at a much lower than normal level.

Now if you want to REALLY confuse people you may discuss transistor beta, operational curves and amplifier bias. Solid state engineering theory you >need< to understand what's going on inside the box. In other words you must learn Greek to impress like a geek, better yet use scientific font in your posts and fill them with advanced mathematics. (;->)

I hope you have learned your lesson, when you ask the time some will tell you how to build a cesium ion laser atomic clock.

Hey, you're right. I asked a simple question or at least I thought it was. And people totally changed the topic arguing about something I don't even know what it is.
 
N

N_Jay

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xpawel15x said:
Hey, you're right. I asked a simple question or at least I thought it was. And people totally changed the topic arguing about something I don't even know what it is.

And worse yet, gave out confusing and incorrect information on that topic. :lol: :lol:
 

Big_Ears

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Not even close to quantum mechanics. It's just plain old solid state physics and typical MOS/Bipolar small signal amplification techniques.
 

Raven95150

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Regardless of why...I can tell you that my Nextel definitely interferes with my 396. Any time I talk on the Nextel with the 396 nearby, a "clicking" sound comes over the scanner. It doesnt seem to affect scanning or reception, you just hear the clicking sound. If the scanner happens to be recieving a transmission, it can be heard in the background but the traffic still comes across the scanner loud and clear.
 

w0fg

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Decorah, IA
Raven95150 said:
Regardless of why...I can tell you that my Nextel definitely interferes with my 396. Any time I talk on the Nextel with the 396 nearby, a "clicking" sound comes over the scanner. It doesnt seem to affect scanning or reception, you just hear the clicking sound. If the scanner happens to be recieving a transmission, it can be heard in the background but the traffic still comes across the scanner loud and clear.

Oh heck, as long as this thread is totally out of control, lets add in discussion of wave form analysis and leading edge key clicks on the make-break transitions.:twisted:
 
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