Southern Virginia / Northern North Carolina

[SH728]

I have recently (within the last 24 hours) gotten my BTECH GMRS-PRO setup... I think.

I am VERY new to this and honestly don't know much about what I am doing. Yes, I have a license. I haven't changed any frequencies that came programmed, rather only changed the names for my OCD sake. In regards to use, myself and a group of buddies plan to use the GMRS system when on "operations" and training exercises utilizing < 5 mile range. What is my best options when it comes to frequencies, high/low, settings, etc. I am not familiar with what high and low bands are, what the correct MHz need to be. Any help would be appreciated.

Anyone close to I-85 near the VA/NC border? Would love to chat and try and test my new GMRS device!

[gortex2]

Not alot to be honest. If you look at the maps there is one near Kerr Lake however from 85 I can't get into it. I am west of that area and my travels across 58 are normally pretty quiet. If your looking to use the radio to chat with folks you may of picked the wrong service. 

https://mygmrs.com/repeater/6282

[KAF6045]

5 hours ago, SH728 said:

I am VERY new to this and honestly don't know much about what I am doing. Yes, I have a license. I haven't changed any frequencies that came programmed, rather only changed the names for my OCD sake. In regards to use, myself and a group of buddies plan to use the GMRS system when on "operations" and training exercises utilizing < 5 mile range. What is my best options when it comes to frequencies, high/low, settings, etc. I am not familiar with what high and low bands are, what the correct MHz need to be. Any help would be appreciated.

Unless using a repeater, or on very open terrain, your range may be much less than 5 miles. UHF is considered a "line-of-sight" service -- for a radio held 5 feet (I'm presuming a "typical" person, if you are all basketball stars running 6.5' or more the numbers will change some) the horizon distance is 2.7 miles. Call it 2.5 just to clear the actual horizon and have the signal pass on... Open fields would then be you 5 mile range (person A to 2.5 closest approach to earth then another 2.5 miles to get to person B).

Woods and buildings will rapidly reduce the range (though UHF can get /into/ buildings slightly better than VHF -- the wavelength at UHF is smaller then many window frames; metal frames at VHF tend to act as a shield).

Frequencies? GMRS is (in current FCC regulations*) split into four channel groups.

• 462MHz GMRS Main (simplex) channels (in the current consolidated numbering scheme: #15-#22), allowed up to 50W output power, (wide) FM. Note that these are also the output frequencies for repeaters, so you may hear repeater traffic on these channels
• 467MHz GMRS Main (repeater) channels (#23-#30 on some units, or #15-#22 with an R/RP/RPTR notation on the display). Again up to 50W, (w) FM. These are transmit only frequencies, for 467.xxx you listen on 462.xxx
• 462MHz interstitial channels (#1-#7). These were channels created in the 90s I believe -- they are centered between the main channels and partly overlap the main channels. Limited to 5W ERP (not transmitter output, but effective power in the main beam of the antenna -- using a high-gain antenna with a 5W transmitter can exceed the 5W ERP!). (w) FM.
• 467MHz interstitial channels (#8-#14). Until the 2017 FCC reorganization, these were FRS-only channels. They split the Repeater input channels. To avoid repeater interference, these channels are restricted to 0.5W ERP and Narrow FM; use of any gain antenna will definitely exceed the ERP limit for practically any GMRS radio on low power (mobile radios do not have these as they typically have 5W as the low power AND have gain antennas).

Unless you are working through a local repeater, you probably won't use ANY channel with 467MHz. Without a repeater no one will hear you if you are transmitting on 467MHz repeater frequencies; the 467MHz interstitials are too low in power to get through any vegetation at the distances you are considering (at close range -- say within a camping site -- 0.5W could be usable).

If everyone is running 5W HTs, the 462MHz interstitials would be candidates (if there are repeaters in the vicinity, you won't come into conflict). If mobiles are in play (or there are too many kiddies with FRS radios sending calling tones on the channels and you need to find a clear frequency), you might use the 462MHz main simplex channels -- a the mobile could use more than 5W power.

CTCSS/DCS tones (many manuals may refer to these as "privacy" codes) may not be desired for your use. The tones do NOT make your transmissions "private" -- anyone with a radio configured for "no tone" can hear you. What the tones do is /block/ transmissions from others that are not using the same tones.

You'll probably be keeping the channels in High power (5W vs 0.5W low) -- unless, as mentioned above, you are in a close range situation where 0.5W is sufficient.

High/Low BAND refers to UHF/VHF frequencies, and likely applies mainly to setting up channels for receive-only/scanning use.

Valid frequencies are listed in FCC Part 95 E. Simplex frequencies will have the same frequency for Tx and Rx; repeater channels will have 467.xxx for Tx and 462.xxx for Rx (note that main channels have 3 digit .xxx [or end with a 0 as in .xxx0; interstitials are .xxx5]).

 

 

* If you haven't, I recommend perusing FCC Part 95 E https://www.ecfr.gov/current/title-47/chapter-I/subchapter-D/part-95/subpart-E [use the Print/PDF item to get a local copy]

 

[WRTQ298]

If you're ever up closer to Richmond or Fredericksburg, I monitor channel 20 and would be happy to talk!