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oj70chevy

FM Transmitter question

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Timon wrote:

No, I was just saying the most people would think that the two signals would step on each other. Paul and I being Hams understand about FM capture where the average Lay person would likely not. It was just to inform those that didn't know.

Not to nitpick, but I believe Paul said he wasn't a ham...but yet he DOES, I'm sure, understand capture effect.;)

And I've met several hams who probably couldn't explain capture effect, and, obviously, non-hams who could.

For the record, I've been licensed as a ham for 35 years, 28 of those as an extra (AE4DW).

I think Pete's point is, your comment came across a bit condescending, whether you meant it that way or not.

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And that brings us to today's point to ponder - the old "PTP", to speak in lay person terms.

Have any of you licensed Hams ever come across any licensed Cheese? Seems like some interesting possibilities...

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Find some licensed mustard, and I am all over it.

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And no, I'm not a Ham Operator, I'm a AM/FM Radio Broadcast Engineer
(Chief Engineer for 22 years)
I did 50kW 3-Phase AM directionals and to many FM's to mention, okay I'll mention
I worked for 17 radio stations in my career

I can get my ham ticket, but as I stated radio is a job for me, not a hobby
this here is my hobby that I have to broadcast for people to hear and my system sounds great,

But I'm obligated as a licensed FCC Operator to pass knowledge along to those who aren't broadcast educated to know what the rules are and what they are doing, and all the Amateur Radio Operators on here have to same obligation to educate, its our jobs and its what we do

here is a video from 2011 and I recorded the audio right off one of my handheld portable FM radios connected right to my camcorder

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PMC wrote:

And no, I'm not a Ham Operator, I'm a AM/FM Radio Broadcast Engineer
(Chief Engineer for 22 years)
I did 50kW 3-Phase AM directionals and to many FM's to mention, okay I'll mention
I worked for 17 radio stations in my career

I can get my ham ticket, but as I stated radio is a job for me, not a hobby
this here is my hobby that I have to broadcast for people to hear and my system sounds great,

But I'm obligated as a licensed FCC Operator to pass knowledge along to those who aren't broadcast educated to know what the rules are and what they are doing, and all the Amateur Radio Operators on here have to same obligation to educate, its our jobs and its what we do











I've had my FCC General radiotelephone license almost as long as my amateur license...I've always seen it as a choice, rather than an obligation or a job, to educate. Each to his own; won't argue semantics. That said, you'll find enough posts from me here trying to "educate" on the topic of proper FM transmitter usage, so I guess I've met my obligation.

I'll bow out of the conversation at this point, and go ponder George's question regarding licensed cheeses. I'm told the Limburger written exam really stinks, while the Blue Cheese exam is a bit aged and outdated. (Sorry, its the best I can do on a Friday night).

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when I was in the "van" one day and we had to track down a pirate radio station and when it was done I was instructed by the FCC that it is my obligation as a licensed representative of the FCC to uphold the laws and tell those who violate that they are in violation.

I was told that 20 years ago

so my obligation on this topic is done

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PMC wrote:

when I was in the "van" one day and we had to track down a pirate radio station and when it was done I was instructed by the FCC that it is my obligation as a licensed representative of the FCC to uphold the laws and tell those who violate that they are in violation.

I was told that 20 years ago

so my obligation on this topic is done

I do have to weigh in here one more time...

You're not deputized, or become a representative or employee of the FCC, when you obtain an FCC commercial license.

So other than an ethical/moral obligation to advise others if they are in violation, there is no other obligation. And you obviously have no right to do anything to a station that is operating in violation, i.e., enter the station location and shut it down.

Further, if you don't advise someone they are in violation, there is no way the FCC will do anything to you unless you are an involved party to the actual activity that is in violation.

If I am in error with my statements, please provide FCC case law reference, or FCC reg references, and I'll gladly admit my error.

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yeah, your right. I didn't take an Hippocratic Oath like a Dr. does

you are 100% correct

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Kind of off topic but I think that there might be some confusion all of the same.

First we have Paul aka PMC who is a commercial radio engineer. Did I get that right Paul (PMC)?

Then we have Paul aka Max-Paul who is a HAM KF0OX. So just calling out Paul when we both are in the thread can get things mixed up a bit.

73

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Jeff Millard wrote:

I stayed in a Holiday Inn Express one time...


nice call. I think I stayed there to. lol

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Steven wrote:

oj70chevy wrote:
If I don't get the rds now can it be added later or is it a one time thing?

Before EDM developed their RDS model, I interfaced an RDS encoder to 3 different transmitters. Read about it here.


I purchased my EDM unit a couple of years ago prior to the RDS encoder option. Are there any after market RDS encoders available that are completed units that do not require soldering them together? Soldering a one or two wires is one thing but a whole kit is not really worth it to me. If not I may just sell my EDM unit and get a RDS unit or just keep it as a back up unit. Of course there is always the option of running two different broadcasts at the same time. I run light shows and video 3D and broadcasting the audio from it would add some new options for me.


I get alot of questions about songs and artists and having the RDS option may just save me having to answer a few questions.

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I did some research and found the following

http://www.pira.cz/rds/show.asp?art=micrords_encoder is a complete micro unit for $24 EUR.

http://www.pcs-electronics.com/rds-max-4000-p-1141.html?osCsid=cf227b26189c2a1d15ec2cf4c44c2ee0 is a complete unit with enclosure for $149.99 EUR.

I do believe it would just be simpler and easier to purchase an EDM unit with the RDS system together rather than trying to add RDS into the system.

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I find it easiest to just list the songs and artists on the info sheets people pick up from my info mailbox on site, and also on the website.

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Personally I'd chuck RDS as there are few that really watch it on their radios and it reduces your range. I'd rather put the money into a matrix in my display.

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How much does RDS effect range?

After all I only need to be able to broadcast to the curb. From what I understand with RDS you may have to locate you antenna outside to be able to broadcast the RDS info.

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I went a different route I purchased a commercial stereo FM modulator (transmitter) that was designed to put a FM channel on a cable system. new they are about $200 ish on Ebay sometimes for about #100. These are rock solid commercial 1u rack mount unit and very easy to add RDS. I use a J-pole antenna I made with copper pipe.

KEN

Lights on Bell Road

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toddmoon wrote:

How much does RDS effect range?

RDS does not affect the range of the audio (FM stereo) signal.

However, to reliably receive the RDS signal, the receiver needs to have a stronger signal (i.e. be closer to the transmitter).

For example, your viewers will be able to hear your music from 2 houses away, but they need to park right in front of your display to get the RDS information reliably.

That's just an example. In your actual situation, you'll have to set up your transmitter and drive back and forth with a RDS-capable radio to know for sure.

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makes since. now so I don't have to add an antenna can i run the audio "via a cat5" from say in my pc in the house and put the transmitter in my truck so i can get the signal closer to the street or does it have to be a fixed audio cable. Im guessing at this point it will be all trial and error to get it right and be within the FCC guide lines.

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Steven wrote:

toddmoon wrote:
How much does RDS effect range?

RDS does not affect the range of the audio (FM stereo) signal.

However, to reliably receive the RDS signal, the receiver needs to have a stronger signal (i.e. be closer to the transmitter).

For example, your viewers will be able to hear your music from 2 houses away, but they need to park right in front of your display to get the RDS information reliably.

That's just an example.  In your actual situation, you'll have to set up your transmitter and drive back and forth with a RDS-capable radio to know for sure.

All additional features you add to an FM carrier will effect signal to noise, S/,N and thus range. Paul, correct me if I error as I'm a but rusty on this. When you add the stereo subcarrier you need more effective power to cover the same area at the same S/N. Add RDS and you need to increase again. If you don't increse power then your effective range will go down.

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oj70chevy wrote:

makes since. now so I don't have to add an antenna can i run the audio "via a cat5" from say in my pc in the house and put the transmitter in my truck so i can get the signal closer to the street or does it have to be a fixed audio cable. Im guessing at this point it will be all trial and error to get it right and be within the FCC guide lines.


You'll need to connect your audio output from your computer to the audio input of the transmitter. Then, locate the transmitter wherever you're able to get a good signal to your viewers.

Last year, I connected the headphone output of my PC to the input of the EDM, hid both under a table in the front room of my house, and taped the included test antenna to a window that faces the street. , I could tune my station reliably almost anywhere on my cul-de-sac. This year, I'm installing a Ramsey TM100 antenna to take care of a couple of pesky locations on the cul-de-sac where I was getting a small bit of annoying interference from the metal cladding on my windows. Works like a charm.

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jimswinder wrote:

You are paying THOUSANDS for the lights and controllers (visual)...why skimp on the audio???

To me...Audio is 50% of the display...if they can't hear AND understand the music/lyrics...what's the point?

It's not just about coverage...it's about the quality...

go with one of the above mentioned...and DO NOT go with a cheap Whole House Transmitter...

I had one and it would not even get outside the window to my car in the driveway less than 20' away

IMO


Maybe becasue it is a "Whole House" not a whole out doors. LOL

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Here is a quick read from the FCC on non-licensed broadcasting

now, the reason why Whole House is sold on Light O Rama's website is because this unit is Part 15 compliant. read the specs, 150ft to 200ft, then read the rules

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