RDS transmission on Baofeng UV-5R

[philm001]

Hello all,

I recently purchased 2 Baofeng UV-5R radios and I am looking to connect them up for repeater functionality. For example, I am going to be connecting them wirelessly by setting the Rx of one to 106.2 and the Tx to 440.4. The second unit will have a Rx set to 440.4 and the Tx to be 106.2. This will function as a wireless repeater (I only need a one way repeater for my application).

My question is this, are the radios capable of repeating the RDS?

I am using the FM RDS to control a device. And I would like to extend the range of my transmitter. (It is currently a little tiny ADAfruit transmitter (https://www.adafruit.com/product/1958)

 

[jwt873]

As far as I know, the UV-5R can't transmit on 106.2 Mhz.

Even if it could, it's not capable of the +/- 75 Khz bandwidth used by commercial FM stations. The UV-5R can only transmit narrow band FM (+/- 5Khz).

 

[KD8DVR]

106 Mhz is not in the amateur radio band. It is illegal to transmit there. 440 is in the amateur radio band. A license is required to transmit there.

AntiSquid Disclaimer: All posted content is personal opinion only and may not imply fact or accusation.

 

[Sconnick]

Well...

The legality has been touched upon.

The equipment limitation has been touched upon.

I think that's it!

 

[Your_account]

It is illegal to transmit there

no its not.

 

[philm001]

Hello all,

thank you for your replies.

please note that I was simply using those frequencies as an example. I am mainly looking at the hardware limitations to see if the radio transmitters could repeat the FM wave with RDS.

I picked those frequencies because these are the first ones that came up in my mind. I apologize for any confusion.

If the UV-5R is unable to repeat the RDS, could anyone recommend some repeaters that can re-transmit the RDS?

(For anyone wondering, I am working for someone that does in fact have a radio liscense)

 

[SCPD]

None of this will work anyhow.
Transmit is 136-174 and 400-512MHZ.
It does not decode RDS.
It does not transmit 106.2 at all nor will it ever.
Any 5 watt walkie talkie is a bad idea for a repeater of any kind.

 

[Your_account]

You need an Radio Encoder for RDS.

 

[philm001]

You need an Radio Encoder for RDS.

The adaFruit transmitter that I am using already comes with an RDS encoder built in. I am wondering if there is an FM repeater that is capable of repeating FM and the RDS transmission. Or is it better to utilize an amplifier.

 

[chief21]

Simply put, a FM broadcast transmission, which contains the RDS information within, requires a very high-bandwidth signal. A two-way FM radio, either commercial land mobile or amateur, is designed to operate with a much lower-bandwidth signal and does not have the capability to transmit a broadcast-compatible signal. The same is true of land mobile or amateur repeaters.

 

[mmckenna]

The adaFruit transmitter that I am using already comes with an RDS encoder built in. I am wondering if there is an FM repeater that is capable of repeating FM and the RDS transmission. Or is it better to utilize an amplifier.

Maybe if you described exactly what you want to do in some more detail, we could make some recommendations. There are likely ways to do what you want, but with the limited information you've provided, all we'd be doing is guessing.

In other words, the details are important, as is what sort of licenses you have, where you are located, etc.

 

[philm001]

Maybe if you described exactly what you want to do in some more detail, we could make some recommendations. There are likely ways to do what you want, but with the limited information you've provided, all we'd be doing is guessing.

In other words, the details are important, as is what sort of licenses you have, where you are located, etc.

Sure thing, I am not 100% sure what kind of license our client has (I am developing this project for a client) but I do know they can handle 5 W are are located in Toledo, Ohio.

I am primarily using the RDS in order to control a device which is capable of recording an FM broadcast into memory. There are additional functions that the device can perform with RDS but the main purpose is for recording an FM broadcast. Maximum time is 30 sec of recording.

So primarily we are developing this for RDS control.

 

[wyShack]

philM001-

RDS information is actually on a sub-carrier of the FM broadcast station. Any 'repeater' you can get "off the shelf' is unlikely to repeat the sub-carrier. Also few if any 'off the shelve' units will handle the FM stereo sub-carrier. As already mentioned, a better description of the problem (general parameters, data ect) will help in finding a solution.

 

[mmckenna]

So, I guess I'm not understanding something...

Why are you trying to repeat an FM broadcast signal? Why don't you just receive the broadcast signal, decode the RDS and use it as is? The extra radios in the middle are confusing me as to their purpose.

 

[philm001]

The FM broadcast is coming from our adaFruit transmitter and we would like to extend the range through a repeater.

The adaFruit transmitter only gives us about 20 - 30 feet.

 

[mmckenna]

Ah, OK, now that makes sense.

So, there are ways to do this, figuring out which one is right is up to you:
1. FCC does Experimental Licenses. That might be an option. It would let you transmit on FM broadcast band, or somewhere close by.
2. Use a long coax run. I know, probably not what you want to hear.
3. You mentioned the company is allowed up to 5 watts? I'd research that and get some clarification.
4. If the company's license allows that, look at what the limit is. Is it 5 watts transmitter output, or 5 watts ERP? If it's 5 watts ERP, then you are stuck with that. If it's 5 watts TPO and there's no limitation on antenna gain, then you can try higher gain antennas to boost coverage.

As others have stated, the amount of bandwidth you need and the ability to handle the subcarriers is going to pretty much limit you to using transmitters designed for the FM broadcast band.

 

[jonwienke]

Not possible. Or legal.

FM stereo broadcast has a much wider channel width than what the Baofeng will handle. You can't repeat a 200KHz-wide broadcast channel through a radio that only does maximum 25KHz-wide channels. Your RDS subcarrier will be lost, and your audio frequency response will be limited to about 300-3000Hz mono, rather than 20-20,000Hz stereo.

Also, there are strict limits on power levels for unlicensed use of FM stereo broadcast frequencies.

You're limited to a range of 200 feet:
https://www.fcc.gov/media/radio/low-power-radio-general-information

https://transition.fcc.gov/bureaus/oet/info/documents/bulletins/oet63/oet63rev.pdf
Note the table on page 15.

 

[Your_account]

The adaFruit transmitter only gives us about 20 - 30 feet.

oke and how big is your feet?!
Ok its is not cheap but maybe with an SDR?

 

[16b]

Sounds like an interesting project, and those little Adafruit boards are neat. Might have to buy me one to play with.

One option for increased coverage would be to have several FM transmitters throughout your desired coverage area, and simulcast your messages on all of them. Of course this would require them to be networked together in some way.