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Repeater question


stockjock

Question

I recently obtained my GMRS license and a Pofung P15-UV, which is an interesting new GMRS handheld radio that I believe is made by Baofeng.  Looks almost exactly like the Radioddity GM-30, but the key layout is a bit different.  So not sure if it's a GM-30 on the outside and something different on the inside or essentially the same radio, albeit with a slightly different keyboard layout.  Let me know if you know.

I'm in the San Diego area and have not been able to locate or use a repeater.  Looks like we don't have many to begin with, which is surprising as we're a good-sized city, but it seems many/all of them require permission.  I did request permission from 3, but have not heard back.

Is there another way to find repeaters to use?  Also, in terms of the CTCSS and DCS codes, do they need to match up with the repeater's codes each time?  Is it necessary to input those for transmit and also receive codes?  I've been involved with radio for many decades, especially shortwave, but this is new to me.

Thank you in advance.

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14 minutes ago, MichaelLAX said:

One last question: is the ducky antenna removable so that I can connect it to my rooftop Comet?

The antenna unscrews once you loosen the small hex nut.  I believe the antenna should have an SMA male connector, but I'm not an expert.  That's what I ordered at least.

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4 hours ago, MichaelLAX said:

Great news: I just used your link to buy one <$30 with sales tax and free shipping to be here September 8th!  

Any success yet hitting your local repeaters? I may need to take a drive down in my EV and help out! ?

No luck so far.  I'm hearing some activity on Repeater 2, but not hitting the repeater.  Been trying to scan for the code, but not sure if it matters whether to search for DCS or CTCSS.  

What if you use a repeater without permission?  As mentioned, I requested permission from I think 3 repeaters (not sure I can even reach them), but no one replied.

Hopefully you will enjoy the new radio.  I'm not that experienced, but it seems like a good unit for the money.

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Just got my license and Radioddity GM-30 last week.  There are two open GMRS repeaters in my area.  I've tested both successfully from about five miles out.  Haven't heard any traffic on either as yet, but then again I'm not sure how many folks actively use them.  GMRS, while it's gaining popularity, is still relatively new compared to Ham in terms of general public awareness.  I don't believe there are any clubs associated with the repeaters I've connected to, unlike the local 2M Ham repeaters I monitor with clubs that meet over the air weekly or monthly.  Amateur radio has more of a hobby aspect to it, as where GMRS/FRS, to my experience, is more geared toward personal two-way communication.  Granted, that may evolve as more people become interested in GMRS.  It would be cool to see a club form in my area just so folks could meet up and share the interest, but that may take some time if the interest develops at all.  For now I just like to listen in on the GMRS club feeds from other areas, be it through this site or my Zello app.

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I think it's an interesting medium with a low bar to entry.  I actually wouldn't mind if they kept the $70 fee in place to keep too many from signing up.  Many years ago, I used a CB radio and watched as it went fully to hell due to it's popularity and low barriers to entry.  Hopefully that won't happen with GMRS, but with CB, one could bounce skip signals across the country, and fortunately that won't happen with GMRS.

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On 9/3/2021 at 12:07 PM, stockjock said:

I think it's an interesting medium with a low bar to entry.  I actually wouldn't mind if they kept the $70 fee in place to keep too many from signing up.  Many years ago, I used a CB radio and watched as it went fully to hell due to it's popularity and low barriers to entry.  Hopefully that won't happen with GMRS, but with CB, one could bounce skip signals across the country, and fortunately that won't happen with GMRS.

I think not enforcing the need to get a call sign had more to do with the decline of CB than anything. 

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The fee for a CB license was lowered to $4 in the mid 70's, and it was still a fairly viable medium until the FCC abandoned licenses altogether in the early 80's.  I don't think the fee amount matters as long as there is some form of consideration involved in getting licensed, whether it's time or money.  Even with the $4 fee, most CB operators back then were responsible just because the license was an investment they wanted to maintain.  The call signs made it more accountable, as it was easier to identify those who were perhaps not playing by the rules.  These days of course, there pretty much are no rules with CB.  I hear people from all over talking skip over each other and bragging about their 200W amps....far cry from the 4W maximum the FCC allowed back in the day.

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Just to follow-up to my original question, MichaelLAX drove down to my area of San Diego from Los Angeles to find some repeaters, which was way above and beyond the call of duty, so thanks to him for that.  Now, I think I know how to do it on my own.  We did find a repeater to use and no one kicked us off, so I suppose if I use it I'll ask permission and let them make the decision.

In San Diego, I think there are 3 repeaters officially listed in myGMRS and 1 mentioned in the footnotes of one of those listings.  I cannot reach 2 of the 4 repeaters and I did ask permission on the other 2, but didn't receive a reply.  Found a new one tonight, but was told it was a paid, private repeater used in fire support, so I will stay off of that one.  But the owner did send me a nice e-mail message.

At least I now know how to find and use a repeater, so thanks for the help.  I might not be able to use too many of them, but perhaps a few options will open up for use.

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On 8/31/2021 at 12:58 PM, stockjock said:

Also, in terms of the CTCSS and DCS codes, do they need to match up with the repeater's codes each time?  Is it necessary to input those for transmit and also receive codes?  I've been involved with radio for many decades, especially shortwave, but this is new to me.

Thank you in advance.

It's my understanding (any I may be wrong) that you don't need a CTCSS tone just to monitor a repeater.  As long as you have CTCSS RX disabled on the radio, you should be able to hear traffic regardless of the repeater's CTCSS TX tone.  The radio should de-squelch the transmissions because it's not listening for any particular tone.

I discovered this playing around with a pair of our FRS handhelds.  I picked a mutual channel and set a CTCSS TX/RX code on one radio while leaving CTCSS disabled on the other.  The CTCSS-disabled radio de-squelched the transmission from the CTCSS-enabled radio when I keyed up.  I then keyed up the CTCSS-disabled radio and that transmission was squelched on the radio with the tone enabled.  CTCSS squelches when the transmit tone doesn't match the tone the receiver is listening for.  A radio with CTCSS RX disabled doesn't care if there's a tone or not.  It lets everything through.

On the flip side, any radio set to receive a CTCSS tone (like a repeater) has to hear that particular tone before it will de-squelch.  If your radio isn't set to transmit the CTCSS tone the repeater is programmed to receive, it will ignore you.

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1 hour ago, DDinMCMI said:

It's my understanding (any I may be wrong) that you don't need a CTCSS tone just to monitor a repeater.  As long as you have CTCSS RX disabled on the radio, you should be able to hear traffic regardless of the repeater's CTCSS TX tone.  The radio should de-squelch the transmissions because it's not listening for any particular tone.

I discovered this playing around with a pair of our FRS handhelds.  I picked a mutual channel and set a CTCSS TX/RX code on one radio while leaving CTCSS disabled on the other.  The CTCSS-disabled radio de-squelched the transmission from the CTCSS-enabled radio when I keyed up.  I then keyed up the CTCSS-disabled radio and that transmission was squelched on the radio with the tone enabled.  CTCSS squelches when the transmit tone doesn't match the tone the receiver is listening for.  A radio with CTCSS RX disabled doesn't care if there's a tone or not.  It lets everything through.

On the flip side, any radio set to receive a CTCSS tone (like a repeater) has to hear that particular tone before it will de-squelch.  If your radio isn't set to transmit the CTCSS tone the repeater is programmed to receive, it will ignore you.

Since we're new at this, hopefully the more experienced will forgive our inexperience.

But that said, I think those tones are basically privacy tones that don't offer actual privacy (conversations can be heard by everyone), but block out others not transmitting the tones on simplex for the listeners that have them enabled.  And also those tones are required to access many repeaters, which are activated by the tone, ingest the weaker conversation on 467.whatever and rebroadcast it on 462.whatever usually without privacy tones.  There's a bit of a learning curve, but starting to get the hang of it (I think).

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It's my understanding (any I may be wrong) that you don't need a CTCSS tone just to monitor a repeater.  As long as you have CTCSS RX disabled on the radio, you should be able to hear traffic regardless of the repeater's CTCSS TX tone.  The radio should de-squelch the transmissions because it's not listening for any particular tone.
I discovered this playing around with a pair of our FRS handhelds.  I picked a mutual channel and set a CTCSS TX/RX code on one radio while leaving CTCSS disabled on the other.  The CTCSS-disabled radio de-squelched the transmission from the CTCSS-enabled radio when I keyed up.  I then keyed up the CTCSS-disabled radio and that transmission was squelched on the radio with the tone enabled.  CTCSS squelches when the transmit tone doesn't match the tone the receiver is listening for.  A radio with CTCSS RX disabled doesn't care if there's a tone or not.  It lets everything through.
On the flip side, any radio set to receive a CTCSS tone (like a repeater) has to hear that particular tone before it will de-squelch.  If your radio isn't set to transmit the CTCSS tone the repeater is programmed to receive, it will ignore you.

You are correct that you do not need CTCSS or DCS codes to listen. And you are correct that despite the term ‘Privacy’ in the acronym PL (Privacy Code), use of codes offers zero privacy. Codes are not used to encrypt or decrypt a signal in anyway.

Codes are ALWAYS used by the squelch circuit of the receiving as a means to filtering out signals. If a signal does not include the code, the receiver’s squelch will not open up (aka ‘Unmute’) and thus the transmitted audio does not pass through to the speaker. There is zero difference in behavior between a cheap FRS radio and an expensive GMRS repeater in this regard. They are used as a means of limiting what you hear over a frequency that is otherwise shared by many. In the case of a repeater, if the repeater does not detect the code it seeks in a signal it receives, it does not retransmit it.


Michael
WRHS965
KE8PLM
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Motorola has a trademark on the term "Private Line" which is usually abbreviated to "PL" but of course it only offers privacy to the listener to block out those transmissions he does not want to hear.  The generic term was originally CTCSS for the analog system.

I make sure my 10 year old grandson's FRS radio has CTCSS turned on for receive, when he communicates to me, so that he is not bothered by other transmissions, including for his safety.

When he expresses an interest in radio communications with strangers, I will explain its meaning to him and then discuss with him how not to give out personal information to strangers (as he already knows not to do in person).

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4 hours ago, stockjock said:

And also those tones are required to access many repeaters, which are activated by the tone, ingest the weaker conversation on 467.whatever and rebroadcast it on 462.whatever usually without privacy tones.

In ham world repeater usually transmits without PL/DPL encoded. Ham repeaters are frequency-coordinated, most of them. You may never encounter two repeaters on the same output frequency. In GMRS repeater usually transmits with tones encoded. GMRS is only 8 channels and not frequency-coordinated, tones are necessity.

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23 minutes ago, axorlov said:

In ham world repeater usually transmits without PL/DPL encoded...

Not so in Southern California; NorCal is different?

The only repeater in SoCal that I am aware of that is not tone encoded, is the Catalina Repeater: 147.09. All* the rest of them require tones.

*Never say Never!  When I use the word "all" I assume that there are one or two other exceptions similar to the Catalina Repeater that I have never used, such as those few listed in the Jet Propulsion Labs 2 Meter Repeater chart for SoCal:

http://rptrlist.w6jpl.ampr.org/2m.htm

But even that chart shows that the great preponderance of 2 meter repeaters in SoCal use tones.

The same is true, but to a lesser extent, in that chart for 440 MHz.

But Axorlov's point is well taken: GMRS repeaters use tones to allow for multiple repeaters on the same limited 8 channels.

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In ham world repeater usually transmits without PL/DPL encoded. Ham repeaters are frequency-coordinated, most of them. You may never encounter two repeaters on the same output frequency. In GMRS repeater usually transmits with tones encoded. GMRS is only 8 channels and not frequency-coordinated, tones are necessity.

Regarding ham repeaters not sending out codes. While that may be a choice that has been made in some areas, that cannot be said as a blanket statement. The amateur repeaters I am using in Cincinnati all send out a code.


Michael
WRHS965
KE8PLM
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Ham repeaters in my corner of NC are a mixed bag as far as tones. Some use them, many do not. N2GE, the repeater on Mt. Mitchell which reaches into 4 states does not use tones along with our club repeater, N4MOE on Mt. Spivey. There are 3 repeaters on Bearwallow. Two of those use tones, the UHF and the GMRS.

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