Channel question

[dirkvan]

I frequently scan using my GM-30 HT.  Recently, I've been picking up the same traffic on Channel 22 and RPT-8. I can hear the exact same conversation on both channels.  Looking at my freq chart for the GM-30, i see that both channels share 462.7250.  I can hear them crystal clear on both channels.  I've done a tone scan for both CTCSS and DCS tones while the traffic was ongoing and didn't get anything.  I've tried raising them but they can't hear me.  Based on the conversation I can hear, I know they are about 30-40 miles from my location.  My question is, what am I picking up?  Is this a repeater on GMRS or might I be hearing something from an adjacent band like HAM or MURS?  I'm a newbie when it comes to all this, so trying to learn, please be patient! Thanks!

[MichaelLAX]

Repeater is my guess; use Rptr-8

if you cannot scan the tones needed to trigger the repeater, it may be split tone . That is different output and input tones.

Can you scan for digital tones as well?
 

Maybe Menu 29 or 30?

Have you looked on this site’s repeater database?

 

Channel 22 is the simplex channel that shares the same output frequency as Rptr-8. Rptr-8 transmits on 467.725

What city or zip are you in Loudin County VA?

[MichaelLAX]

Could it be one of these two repeaters?

https://mygmrs.com/repeater/2776
 

https://mygmrs.com/repeater/2329

[dirkvan]

16 hours ago, MichaelLAX said:

Repeater is my guess; use Rptr-8

if you cannot scan the tones needed to trigger the repeater, it may be split tone . That is different output and input tones.

Can you scan for digital tones as well?
 

Maybe Menu 29 or 30?

Have you looked on this site’s repeater database?

 

Channel 22 is the simplex channel that shares the same output frequency as Rptr-8. Rptr-8 transmits on 467.725

What city or zip are you in Loudin County VA?

I have scanned both DCS and CTCSS tones.  I can hear both sides of their conversation, which is what confuses me.  If they were using split tones, wouldn't I only hear one side of the conversation?  I live in Lovettsville, VA 20180.  I have both of those repeaters and their codes programmed into my unit, but I don't hear them on those channels.  From what i can deduce from the conversation, it is some kind of business that installs radio infrastructure for the county and various other businesses.  In addition to voice traffic, i hear them talking alot about carrying fire and alarm signals on a radio network.  Whatever system they are on in their vehicles, it is the strongest and clearest signal I've heard so far on GMRS!  They occasionally tell each other to switch over to the "shop channel" and then I lose them.  I have not heard them use any GMRS call signs.

Thanks for helping me puzzle through this!

[gortex2]

MY guess is they are using simplex on the frequency for truck to truck or other comms. Doubt they have a license. 

[wayoverthere]

1 hour ago, dirkvan said:

I have scanned both DCS and CTCSS tones.  I can hear both sides of their conversation, which is what confuses me.  If they were using split tones, wouldn't I only hear one side of the conversation? 

Only if you have a tone set on your receive....think of tones as a filter on what you hear, rather than keeping others from hearing anything. If you have a tone set, you only hear signals with that tone. If you have no tone set, there's no filter in place, so you hear everything on the channel.

[n4gix]

You cannot scan for the repeater's input tone with regular GMRS equipment, and that is what you will need to use the repeater if indeed it is a repeater.

[MichaelLAX]

1 hour ago, n4gix said:

You cannot scan for the repeater's input tone with regular GMRS equipment, and that is what you will need to use the repeater if indeed it is a repeater.

You mean only if it is split tone, but even then what I do is:

He can drive up near the repeater with his GM-30, and listen on the input frequency (467.725) and scan the tone of those getting access to the repeater

[dirkvan]

43 minutes ago, MichaelLAX said:

You mean only if it is split tone, but even then what I do is:

He can drive up near the repeater with his GM-30, and listen on the input frequency (467.725) and scan the tone of those getting access to the repeater

I really do appreciate the help here! Not to be obtuse, but isn't what you suggest in essence what I am doing? I have my GM-30 on channel 22 (462.725) and  the nactivate the SEEK CTC function (menu item 30) and it starts scanning for the CTCSS code as soon as it hears something on that channel.  When it stops on a code and I can her the traffic, I'm assuming that's the code that individual is using.  Maybe I'm misunderstanding this whole thing  

[MichaelLAX]

Your understanding is correct most of the time when repeaters are set to use the same tone for transmit and receive. 
however some repeaters are Split Tone and use different tones for transmit and receive. 
In that case your method only gets you the receive tone but you are still unable to access the repeater when you transmit 

My method tells you how to discover the “encode” tone when it is different than the “decode” tone on split tone repeaters

And once you discover the encode tone be sure to program it into your GM-30 in the correct place, whether manually or using a computer. 

[wayoverthere]

37 minutes ago, dirkvan said:

I really do appreciate the help here! Not to be obtuse, but isn't what you suggest in essence what I am doing? I have my GM-30 on channel 22 (462.725) and  the nactivate the SEEK CTC function (menu item 30) and it starts scanning for the CTCSS code as soon as it hears something on that channel.  When it stops on a code and I can her the traffic, I'm assuming that's the code that individual is using.  Maybe I'm misunderstanding this whole thing  

If you're listening to the output from the repeater, what the scan will pick up is the tone coming out from the repeater, which may not be the same as what it wants to get IN.  to scan for the tone to get into the repeater, you have to pick up some other traffic carrying that tone going into the repeater.

This is the reason listening on the same frequency (467.xxx) that the repeater is listening on....you want to hear the traffic TO  the repeater, not coming FROM it.

[dirkvan]

1 hour ago, wayoverthere said:

If you're listening to the output from the repeater, what the scan will pick up is the tone coming out from the repeater, which may not be the same as what it wants to get IN.  to scan for the tone to get into the repeater, you have to pick up some other traffic carrying that tone going into the repeater.

This is the reason listening on the same frequency (467.xxx) that the repeater is listening on....you want to hear the traffic TO  the repeater, not coming FROM it.

OK, now I'm starting to get my thick head around it! Thank you guys so much for elmering me on this one!