Jump to content

GMRS channel plus CTCSS or DSC tone a new real channel?


mitzvah

Recommended Posts

Programmable slot - would be a better name. The RX and TX frequencies and the RX and TX tones. You may have different repeaters on the same 462.650 MHz (on the same channel) with a different TX and RX tones. You can program them into different slots, assigning different names.

Or, you may use the same 462.650 MHz with 110.9 tone to talk to your wife, and the same 462.650 MHz with tone 88.5 to talk to your girlfriend. You can program them into different programmable slots and assign different names.

Link to comment
Share on other sites

16 minutes ago, axorlov said:

Or, you may use the same 462.650 MHz with 110.9 tone to talk to your wife, and the same 462.650 MHz with tone 88.5 to talk to your girlfriend. You can program them into different programmable slots and assign different names.

Yes and both your wife and your girlfriend will be able to hear the others conversation! ?

Link to comment
Share on other sites

1 hour ago, WRQV528 said:

Ah, yes, because strictly speaking, @axorlov didn't say that each woman's radio was configured to use any tone on that frequency.

Even if @axorlovhad said that each woman's radio was configured to use any tone on that frequency, it would be misleading to assert that the husband could rely on any "privacy" tones.

Link to comment
Share on other sites

Midland's GTX1000 handhelds are sold this way: 50 channels. Of those 50, 22 are frequencies corresponding with GMRS 1 through 22. And then 23 through 50 are those same frequencies preprogrammed with either CTCSS or DCS codes. Those codes are squelch codes. This means that they are codes someone must transmit for your receiver to open squelch and listen to the transmission. Or that your transmitter must send so that receivers programmed with the same codes will open their squelch and listen.

 

Any receiver that is not programmed to require a squelch code to open squelch will default to receiving all transmissions on a given frequency. And those transmissions are in no way encrypted (GMRS doesn't allow for scrambling). So conversations held between transceivers operating with squelch codes are openly available to transceivers or scanners that are not set to limit by squelch code. There is no privacy.

 

At any rate, channel 50 in a Midland radio, for example, is going to be one of the 22 GMRS frequencies, and one of the conventional CTCSS or DCS codes. If you transmit on channel 50 at the same time someone is transmitting on the equivalent standard GMRS channel, you'll be stomping on each other, because they're analog transmissions on the same frequency. There are only 22 real channels. Everything else is just a preset code on top of one of those 22. 

Link to comment
Share on other sites

The ratio is even worse for the BTech MURS-V1. It has "15" channels.

1-5 are the MURS channels with no codes
6-10 are the same MURS channels with CTCSS codes preset (but programmable if one doesn't like the default)
11-15 are the same channels using preset DCS codes.

I've reset mine so bank one is standard MURS (1-3 NFM, 4-5 WFM), low power, no tones. Bank two is high power. Bank three is back to low power, but with 4-5 set to NFM (only 4-5 have option for bandwidth).

Link to comment
Share on other sites

8 hours ago, axorlov said:

I was simply explaining what "channel" means in the context where there are 128 of them. Unlimited opportunities!

Whoops, I guess I read too much into your post then.

 

This thread has inspired me to make a table of how "privacy codes" are not such. I hope many find it helpful. The forum scales down the image and makes it a little blurry; see the attached ZIP for the original in actual size.

HowPrivacyTonesReallyWorkVersion2.thumb.png.26cb1b6eb96872f181baa9d80c020d07.png

 

HowPrivacyTonesReallyWorkVersion2.zip

Edited by WRQV528
Version 2: Fix typo of "DCS"
Link to comment
Share on other sites

1 hour ago, WRQV528 said:

<..>

Noble effort, but wasted. People who posses the skill of reading would already know this. On the other hand, congregation of the Church of NotaRoundhead will seek guidance and solace in the video sermon of the Queen-Prophet, conveniently linked above by MichaelLAX.

Link to comment
Share on other sites

I have used the CTCSS and DCS codes I’ll skiing in biking so that I do not have to hear other people’s conversations. It is harder when you are skiing and biking to change your channel because your radio keeps breaking squelch caused by a far away user that is nothing but static. I would not go as far to call that a channel but I do like the term programmable slot. Calling It channel is leaning towards false advertising. I have seen radios like that in the past that are marketed as having thousands of channels which is not correct.

What is nice about programmability is you can also change the channels for send and receive. In other words one channel is used to transmit and another channel is used to receive on one radio. The other radio has the opposite configuration. The idea behind this was to have at least 1/2 of a conversation is less likely to be interrupted by others. I wrote about it earlier in a previous post along time ago.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use and Guidelines.