Insane or Possible? (Simulcast Fix)

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ScubaJungle

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I've had this idea for a while and want to know if anyone with more knowledge can verify its insane or can work..
If you are having trouble picking up simulcast in your area, and have, say a BCD436HP, couldn't you theoretically put some kind of aluminum foil or something to block the signal coming from every direction except ONE, so that it doesnt have all the signals hitting it at different times?

Something like a cylinder of foil with a 60-90 degree opening from the center?

Possible?
 
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Possible?
Tin Foil is not directional.

You need a Yagi to have a chance. It's highly directional.
 

KevinC

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A corner reflector would be even better.

ETA...If you were inclined to use this method as opposed to getting a radio that properly handled CQPSK/LSM.
 

ScubaJungle

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I think you may have misunderstood. I agree with the yagi, but what I meant was not to use it for directionality, rather to BLOCK all signals from every direction except where the cylinder/box is opened. For example, you're surrounded by 4 simulcast towers, N, S, E, & W. You make a cylinder/box/whatever out of some efficient RF blocking material, and make an opening facing only east, effectively blocking every tower except that one, preventing the "simulcast issue".
I'm not well versed in materials that are efficient at blocking radio waves, but assuming that material/metal was used, would it work?

Unfortunately I can't afford an SDS100, I got a BCD436HP.

That said, I don't believe I'm going to have this issue nor am I having it - I was just curious. More of a theoretical question I was wondering about, possibly to help others having the issue.

Thanks for the replies.
 

ind224

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Yes, tin foil will work to block RF. Perhaps putting a ball of foil in a microwave on high will convince others that don't believe it. I don't understand the flippant attitude. As for the yagi comment, I have a yagi pointed like this (see pic almost into the ground) to give me 99% decode on a troublesome system.
 

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marksmith

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You would have a much better chance by just using a lousier antenna, which results in only receiving the strongest signal. In order for it to work reasonably there has to be a difference in signal strength of the sites being received. If you are getting strong signals from numerous sites, nothing will work. Even a tyagi might not work.

Use a paper clip instead of an actual antenna. Lousier the antenna the better, and at best it is a not great solution.
 

RFI-EMI-GUY

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Even a lousy antenna is going to pick up some of the interference. It is a signal to noise RATIO problem with the noise being signals coming from sites that are out of phase. The tin foil idea might work if you build a wall around the antenna. But that might be physically challenging. You coukd use 4 by 8 sheets of galvanized steel and pressure treated wooden supports.

The corner reflector antenna is probably the best approach.


You would have a much better chance by just using a lousier antenna, which results in only receiving the strongest signal. In order for it to work reasonably there has to be a difference in signal strength of the sites being received. If you are getting strong signals from numerous sites, nothing will work. Even a tyagi might not work.

Use a paper clip instead of an actual antenna. Lousier the antenna the better, and at best it is a not great solution.
 

ScubaJungle

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A corner reflector would be even better.

ETA...If you were inclined to use this method as opposed to getting a radio that properly handled CQPSK/LSM.
This is exactly what I was imagining. I didn't really know that they were a thing. Thanks for the replies everyone, hopefully this can help someone out thats having trouble with simulcast reception.
 

mmckenna

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This is exactly what I was imagining. I didn't really know that they were a thing. Thanks for the replies everyone, hopefully this can help someone out thats having trouble with simulcast reception.

A cardboard box with the sides covered in aluminum foil can achieve this pretty easily. You can cover two intersecting sides and make a basic 90º corner reflector. You could cover all but one side and make a basic waveguide.
Spacing of the antenna to the aluminum foil will be important.

It's a good idea and something that's easy to do. I'd suggest giving it a try, not like it's going to cost you a lot of money.
 

mmckenna

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Seriously guys, your answers are not very helpful to the OP without some backup material. Why would he or she be wasting their time? Why are the odds not good? Help the OP learn from your knowledge.

A directional antenna will improve the received signal from one direction and reduce signals from other directions. You can research Front to Back ratio, antenna gain, etc.
Making your own antennas is just part of the hobby. It's easy to go out and buy one, but it takes a bit of skill to build your own. I know that some of the guys discouraging that are hams and have likely built their own antennas at one time or another.

Will it work? Who knows, too many variables to make an informed decision over the internet. But a cardboard box and some aluminum foil/metal window screen, sheet metal, etc. can be cheap. On a rainy weekend, with most of us under "stay at home" restrictions, it's something to pass the time. It might be an unmitigated failure, or it might work well. Who knows, with a good directional antenna, you may hear signals you haven't been able to receive before. There's certainly no harm in trying. It's a hobby, that's what it's about.
 

jonwienke

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Seriously guys, your answers are not very helpful to the OP without some backup material. Why would he or she be wasting their time? Why are the odds not good? Help the OP learn from your knowledge.
There are literally thousands of posts here on the subject of simulcast reception problems already, a click on the search button away. There is nothing new in this discussion, it has been going on for years. There's plenty of "backup material" if you bother to do even a cursory search.

I don't mean to sound like a jerk, but I don't see the value in writing a detailed multipage dissertation to answer a question when there are thousands of posts and multiple wiki articles on this site already devoted to the subject, a simple search away.
 
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