Tone

[M1A308]

What does tone in and tone out mean ? Is it tone in (receive ) and tone out (transmit)? I’m new to this. 

[WRAK968]

Tone in usually refers to RX, Tone out is TX.

[Radioguy7268]

... and Tone would be referring to the PL (Private Line) Tone - usually expressed in Hertz (Hz).

[mbrun]

GMRS radios as well as FRS, MURS, Amateur, Commercial and other radios use a technique of transmitting and requiring receipt of a tone (one you will not hear) for the purpose of allowing the receiver (you and your radio) to limit which transmissions are heard. By quick example. Say you have two radios that feature this capability. If both radios are set to Channel 1 and radio ‘A’ is set to transmit a tone of ‘100.0’ and radio ‘B’ is set to also use ‘100.0’ tone, then the user of radio ‘B’ will hear transmissions from radio ‘A’. If however radio “B” is set to receive a tone of ‘67.0’ then the user of radio ‘B’ will not hear the transmissions from radio ‘A’ because they are not using the same codes.

 

In practice, consider also the following scenario. You live in a neighborhood. Every family in the neighborhood has compatible radios and every family uses the same channel. If all families used code ‘67.0’ then everyone in the neighborhood would hear the transmissions of every other radio in the neighbor. This may be good if you were all working neighborhood watch the same evening, but bad if you only wanted to communicate with and hear members of just your family. If you only wanted to communicate with your family, you could set your radios to transmit and receive on a different code of say ‘100.0’ which has the effect of filtering out signals from other local users.

 

Tones are ‘Squelch Codes’ because they are used to control when the squelch (mute function) of your radio opens up so you can hear it. The terms PL (private line), DPL (digital private line), CTC/CTCSS (Continuous Tone Coded Squelch System), DCS (Digital-Coded Squelch) are all used in connection with squelch control.

 

When you see a repeater that gives a ‘tone-in’ value, it is saying the repeater will recognize your radio and will retransmit your signal if you supply the designated tone in your transmission. If the repeater lists a ‘tone-out’ code, it is saying the repeater will transmit that code so that you can use it on your radio to filter out all other transmissions on its frequency that do not use the same code.

 

Codes make it more enjoyable to share a limited set of frequencies with your citizen neighbors without having to hear every conversation that may be occurring. You can always turn off the receive code on your radio which then allows you hear everyone’s transmissions on your current channel.

 

 

Michael

WRHS965

KE8PLM

[MacJack]

Thanks Michael.  Question any advantage of having two different codes for Rx and another for Tx?  I was playing with that with my two handhelds and could not get it to work.

Jack

GMRS radios as well as FRS, MURS, Amateur, Commercial and other radios use a technique of transmitting and requiring receipt of a tone (one you will not hear) for the purpose of allowing the receiver (you and your radio) to limit which transmissions are heard. By quick example. Say you have two radios that feature this capability. If both radios are set to Channel 1 and radio ‘A’ is set to transmit a tone of ‘100.0’ and radio ‘B’ is set to also use ‘100.0’ tone, then the user of radio ‘B’ will hear transmissions from radio ‘A’. If however radio “B” is set to receive a tone of ‘67.0’ then the user of radio ‘B’ will not hear the transmissions from radio ‘A’ because they are not using the same codes.

In practice, consider also the following scenario. You live in a neighborhood. Every family in the neighborhood has compatible radios and every family uses the same channel. If all families used code ‘67.0’ then everyone in the neighborhood would hear the transmissions of every other radio in the neighbor. This may be good if you were all working neighborhood watch the same evening, but bad if you only wanted to communicate with and hear members of just your family. If you only wanted to communicate with your family, you could set your radios to transmit and receive on a different code of say ‘100.0’ which has the effect of filtering out signals from other local users.

Tones are ‘Squelch Codes’ because they are used to control when the squelch (mute function) of your radio opens up so you can hear it. The terms PL (private line), DPL (digital private line), CTC/CTCSS (Continuous Tone Coded Squelch System), DCS (Digital-Coded Squelch) are all used in connection with squelch control.

When you see a repeater that gives a ‘tone-in’ value, it is saying the repeater will recognize your radio and will retransmit your signal if you supply the designated tone in your transmission. If the repeater lists a ‘tone-out’ code, it is saying the repeater will transmit that code so that you can use it on your radio to filter out all other transmissions on its frequency that do not use the same code.

Codes make it more enjoyable to share a limited set of frequencies with your citizen neighbors without having to hear every conversation that may be occurring. You can always turn off the receive code on your radio which then allows you hear everyone’s transmissions on your current channel.


Michael
WRHS965
KE8PLM

[mbrun]

Good Afternoon. It is merely an added feature that can at times benefit repeaters owners needing to make it more work (read more time consuming) for unauthorized users to gain access. While some radios do have the ability to scan for the codes sent out by the repeater and used by you to control local squelch, the radio cannot as readily scan for the code that it may take to open the repeater up. Bottom line, if the tone to open is different from tone sent out unauthorized users have more work to do to hack their way in and many may just walk away.

 

Regards,

 

Thanks Michael. Question any advantage of having two different codes for Rx and another for Tx? I was playing with that with my two handhelds and could not get it to work.

Jack

 

Michael

WRHS965

KE8PLM

[stevemiller000]

Being new to this I need a clarification. mbrun in your post you gave an example of a neighborhood using the system for a 'watch'. Given that scenerio, here's the question:

Assume the whole neighborhood is using (for example) frequency XXX.xxx but Group A has set the tone to 100 and Group B has the tone set to 50 are you saying that Group A will not hear Group B (or am I totally mixed up and need to do some more reading)?

[mbrun]

Good afternoon Steve.

 

Yes, that is correct.

 

The codes make is possible for multiple groups to share the same frequency, but allows you and other members of your group to limit what you hear to only those transmissions that use the same code.

 

Now, this does not mean that two groups can use the same frequency at exactly the same time. You should not. If you do, you will interfere with one another and either your communications or the other parties will be adversely affected. At their essence, the codes make it possible for your radio to remain silent except for when someone transmits using the same code you have your radio set to.

 

When you want to listen to any transmissions that might be occurring on a given frequency, you either press the “monitor” button on your radio, or disable use of any receive code on your radio.

 

I hope this helps.

 

Being new to this I need a clarification. mbrun in your post you gave an example of a neighborhood using the system for a 'watch'. Given that scenerio, here's the question:

Assume the whole neighborhood is using (for example) frequency XXX.xxx but Group A has set the tone to 100 and Group B has the tone set to 50 are you saying that Group A will not hear Group B (or am I totally mixed up and need to do some more reading)?

 

Michael

WRHS965

KE8PLM

[stevemiller000]

Thanks, that definitely does help