KAF6045

Since you didn't state what radio is in use, one can not look up the manual. Most radios I've seen that use a "chart" are pre-2017 bubble-pack radios from Midland and Motorola (and the Midland MXT series of mobiles). And that is likely because they don't have display space for the real tone designations, hence the use of a linear numbering scheme. I'm sure if you try to program a channel /on/ the radio, you will find you need that chart.

Congratulations on getting a DB20-G that shows 20W. While I expect some variation for my MFJ-847, near 50% error I don't believe in (on VHF it is within 2% of a Diamond SX-200 [the 200 is HF-200MHz, so can't test it on GMRS frequencies]). I'm on my second DB20-G via Amazon, returned the first as my meter is only showing 11.9W for the middle of the repeater band -- into a dummy load, and I went out of my way to reduce losses: meter coupled to radio using a double-ended PL-259 gender changer; if I had a second I'd connect the meter to the dummy load with it rather than using 18" RG-213). Unlocked, and with frequencies entered for bands that the (intended) antenna will never match: DB20-G rated (manual) 18W sold as 20W Channel Low Middle High MURS 4 5.1W 12.6W 22.1W Illegal as MURS is limited to 2W Marine 16 5.6W 13.0W 21.9W GMRS 01 3.8W 6.5W 13.5W Only Low is legal, 5W max #01-#07 GMRS 15 3.8W 6.5W 13.5W Lowest GMRS frequency GMRS 22 3.8W 6.5W 13.4W Highest (simplex) frequency Rptr 15 3.1W 5.2W 11.9W Lowest (repeater) frequency Rptr 22 3.1W 5.2W 11.8W Highest GMRS frequency MXT115 rated 15W Channel Low High GMRS 15 3.9W 12.6W GMRS 22 3.8W 12.6W Rptr 15 3.6W 12.4W Anomaly? Rptr 22 3.6W 12.6W Basically, the same low power readings as the unit I returned. I didn't bother with 2m/70cm frequencies as it will be mounted right next to a 50W Icom ID-5100 dual-band. I suppose I'll keep it, since I wanted it for two reasons: selectable (W)FM/NFM, and (unlocked) ability to save many more /named/ repeater configurations (currently 13 statewide, and 16 for an RT97). It is definitely under-powered on repeater frequencies. The 15W MXT115 (no named channels, NFM-only, only 1 config per channel) is showing 84% of rated power (2.5W low) across the band. This 18W DB20-G, OTOH, is only 66% of rated power on GMRS repeaters, and 75% on GMRS simplex. Yet it is 122% on 155MHz frequencies which it wasn't even sold for... VHF Low and Middle power matches UHF Middle and High power. The measured power is just close enough to not feel like I'm losing anything from the MXT115. The DB20-G was measured powered from an Alinco 30A 13.8V supply (normally powers a Kenwood TS-590); it showed 13.5V on the radio so either that is a lossy power-lead, or just poor calibration in the radio. The MXT115 had the same power meter/dummy load configuration, but was powered from a running vehicle (I have it wired to the battery -- need to find power-lead quick disconnects and an in-line fuse for the DB20-G to fully replace the MXT115 install).

First approach -- apply RF noise filters to all power leads (radio and light bar). Maybe reroute power leads (how are you powering the MXT115? via lighter socket or did you cut off the plug and wire direct to battery?). This presumes the main source of RF IS in the cabling. If the LEDs themselves are emitting, I have no suggestions -- contact the manufacturer and complain about excessive RF noise from the lights.

Unmentioned: DTCS Pol would likely be "NN" (send/receive I presume).

Per https://www.timesmicrowave.com/Calculator?Product=RG-8/U&RunLength=50&Frequency=467 you'd have 2.3dB of loss for that cable at GMRS frequencies. If the HT is putting out the rated 5W, the antenna is only seeing 3.8W. LMR-400 https://www.timesmicrowave.com/Calculator?Product=LMR-400&RunLength=50&Frequency=467 would have 1.4dB loss => 4.25W at antenna Is it enough to make a difference WRT your antenna? I can't say. You state reaching some repeaters, but not others, but without a map showing antenna, nearby buildings, etc. I can't guess at what may interfere. All I /can/ state is that that antenna is too low for my comfort, with too much clutter nearby (even though that hanger/bird nest/feeder is below the ground radials of the antenna, if it is wrought iron it /may/ affect the pattern, adding some directionality to your antenna; this also applies to mobile installations -- the strongest signal tends to extend in the direction /away/ from the most metal).

And following on... If the OP finds distracting (non-repeater traffic) on those channels, THEN set tone mode to TSQL (or whatever Chirp calls it), and set the tone in the ToneSql column.

One thing not mentioned is the possibility for the noise to be some form of intermodulation. The other RF sources may not be on GMRS frequencies, but are such that they are mixing together to create noise at 462MHz.

Hmmm... I don't recall encryption, per se, being allowed in Amateur. Experimental Frequency Hopping Spread Spectrum I do recall -- and the hop sequence had to be public. See Note that "base station" is NOT in the list allowed to transmit on the 467MHz main (repeater input) channels. This section considers a "base" station as something other than a "fixed" station. Fixed stations are limited to 15W output. (This also reinforces my view that just /using/ a repeater via PTT does NOT make that user/radio a "control station" -- to my interpretation a control station must have the ability to shutdown a malfunctioning or misused repeater, not just make it retransmit signals as part of normal operations. Otherwise EVERY user of a repeater is a control operator of that repeater -- rather than the licensee and those authorized by the licensee.) You practically described the one repeater I know is in my area -- and is a grandfathered license belonging to the government of Grand Rapids, with CTCSS tone posted (in the 1997 GMRS National Repeater Guide) for Emergency/Traveller Assistance only. 290 feet above average terrain (769 above sea level), 200W ERP with 50W transmitter. (WXMI-17 used to have on on their tower at over 500ft, but only 60W ERP, claimed 40 mile range, I'm only 25 miles from it... EMERGENCY ONLY in the guide book, not even traveller assistance)

If planning a base station, you really want to get the antenna above the roof line. Using an artificial ground-plane (by this I mean one not built into the antenna itself) just feels like adding complications. Fitting the half-wave at the top of a 6ft pole does put it a few wavelengths above real ground (wavelength for 465MHz [splitting simplex and repeater]) is ~65cm (2.1ft). Call it three wavelengths up from real ground (for purposes of the graph, I had EZ-NEC rescale the generic to 465MHz, and set the bottom at a height of 2m (a bit over 6ft) Maximum gain is 6.03dBi at a takeoff angle of 4deg. However, with such a low (relative to buildings) height, you are sending your energy through all the buildings between you and target (at least, until the 4deg rise brings you above neighboring buildings). Also, with a 50W transmitter, and the antenna just above head height, you may run into RF Exposure problems. I don't know how long a coax you are planning to run, nor what type: assumption -- 20ft Belden 9913... Coax loss drops power at the antenna to 44W, assume you talk one minute out of every three; for effective purposes, ignore the distance to area of interest -- look at the compliance distance figures. You, as "knowing" operator need to stay 3 feet from the nearest part of the antenna to meet FCC exposure criteria. Visitors, who don't know about RF exposure concerns, have to be kept 6.5 feet from the nearest part of the antenna. (For the real nasty version: https://www.govinfo.gov/content/pkg/FR-2020-04-01/pdf/2020-02745.pdf ) Evaluation for: GMRS vertical half-wave at 6ft Input Parameters Power to Antenna (from Exemption Worksheet) 43.95 Watts TX Time Ratio (TX / (TX + RX)) 0.330 Antenna Gain in dBi (dBd + 2.15) 6.03 dBi Operating Frequency 465.000 MHz Ground Reflection Included True Distance to Area of Interest 10.00 Feet Maximum Permissible Exposure (MPE) Controlled Environment 1.550 mW/cm^2 Uncontrolled Environment 0.310 mW/cm^2 Operating Mode/Factor: FM/AM/RTTY/PSK-31 (100%) Average Power at the Antenna 14.504 Watts Estimated Power Density at AoI Distance 0.12749 mW/cm^2 Compliance Distance AoI in Compliance Controlled Environment 2.87 feet True Uncontrolled Environment 6.41 feet True

As far as I know, the KG-935G is a /single receiver/ (regardless of that "two radios in one!" comment on page 25) that rapidly switches between A & B selections. It is not a true dual-receiver that has separate receive modules for each A&B -- you can't hear traffic in both A&B at the same time. In effect, the unit is "scanning" between A & B. Since real scanning requires rapidly switching the scan side from channel to channel, it is quite reasonable that the unit spends all its cycles on just the scan side and doesn't have time to spend on the non-scan side. Compare the description of priority channel scan (page 33 in manual) which just puts the priority between each linear channel during a scan.

The BR-6140 is a half-wave dipole, having ~2.15dBi (0dBd) gain. Mounting closely over a ground plane is going to distort the radiation pattern (probably sending most of the energy up into the sky rather than horizontally). Generic (hence the 300MHz) vertical half-wave dipole in free-space: Oh, you'll want to compare the 3dB beam width too... The 3dB points are where the power is half of the maximum. Same antenna located 1/4 wave above ground: Strongest signal is on a 14 degree take-off angle -- might be good if you are only trying to reach repeaters on tall mountains. Note the reduction in gain, however -- 1.89dBi Located 0.01 wave above ground (the NEC2 software core doesn't like wires touching actual ground, and I can't justify paying LLNL for a license to NEC4 or NEC5): Smoother lobe, but a 19deg take-off angle. But only 0.79dBi gain! Mounted 20 wavelengths up: Take-off angle is only 2deg, practically horizontal -- and with ground effects nearly 7dBi gain The Nagoya requires a ground plane, and using just raw dimensions is 1.5 wavelengths long. I'm not sure if it is base-loaded, center-loaded, or both (I'm used to antenna with a central "lump" being center-loaded -- better radiation pattern, but also more wind drag). Or possibly the center lump is a phasing system and the antenna acts as two phased stacked verticals -- a 5/8 wave is 0.625 wavelengths long, so two stacked 5/8 waves could be about 1.5 waves long. NOTE: the Nagoya is a 6dBi antenna. That's twice what the half-wave dipole has for gain unless the half-wave is mounted, as shown, 20 waves above ground (actually, with the bottom just one wavelength above ground, the half-wave shows around 6dBi, but with a higher take-off angle). Presuming it is mounted on a proper ground-plane, it should outperform the half-wave mounted close to ground. At one wavelength above ground, the half-wave will start to compete with it.

Not really related -- but I'd bet 50% of those hearing the phrase "spurious emissions" will believe it is a reference to "wet dreams". I've not found MEK in any hardware/paint store in my current locale (Grand Rapids vicinity). Tri-Sodium Phosphate for use in pressure washers has also disappeared from said facilities.

I suspect you will never see encryption allowed -- so far the only services that seem to permit encryption are the portions that fall into Land-Mobile Public Safety licenses. Their licenses are for specific frequencies, not the shared-use frequencies of CB/GMRS/MURS/FRS (and Amateur) [cf: 95.381] As for antenna height etc. There is the problem of the grandfathered /business/ licenses. Prior to the October 2017 reorganization, base stations were restricted to 20 feet above the building or structure on which the antenna was mounted. Difficult to restrict an antenna to 50 feet if it is mounted on top of a 10 story hotel or government building. The difference between 5W and 50W (if memory serves) is only 2 S-units on a calibrated S-meter, and translates to only ~twice the potential distance (taking into account line-of-sight obstructions). Most of the (business sponsored) repeaters in my 1997 GMRS Repeater Directory are using antennas with enough gain to have a 250W ERP. 4W /carrier/ on AM, 12W PEP on SSB -- different measurement schemes... Probably similar actual power if one considers a 4W carrier with two sidebands each carrying 4W of signal; SSB just gets to shove all that power into one sideband ? There was a thread somewhere on this forum that did reference a response from the FCC with regards to connections... As best as I could interpret that response, an internet connection using a TV Cable system cable [copper or fiber] was deemed acceptable, but a DSL-type modem on a phone line [again, copper or fiber] was not acceptable, for purpose of linking repeaters. The mere physical connection to the PSTN system seemed to be the hanging point, less than if it had the ability to "patch" into the telephone voice system.

I'd be more concerned about having a stack of adapters as long (and as bulky) as the apparently highly rigid antenna itself presenting a risk of physical damage. Most rubber ducks at least have some give when something hits them on the side. That stack (which appears to be SMA->TNC, TNC->SMA) looks to have left a large torque point on the radio's SMA connector; nothing braces the bottom of the stack against the body of the radio (in my experience most SMA rubber ducks make contact with the retaining ring of the SMA connector, or provide a washer/o-ring to fill any gap). But then, I also still own HTs that use BNC connectors for the antenna... (RatShack and Midland CB; Maxon GMRS-210+3, RatShack (Maxon) HT-202, Pryme PR-52 -- the only one still on the market, to my knowledge, is the Midland)

Looking at "a" web site, it has a warning that it isn't optimized for WinXP -- which was the last of the Win9X core as I recall, Win7 using the NT core. Does claim W95, W98, W2K, and Win NT4 compatibility (and the download/purchase links are dead ends -- the Amazon link brings up OmniPage!), the second I tried just sends you to the first if you want to buy, and the third actually had a working Amazon link -- stating the product is unobtainable...

For "short range" you have to go back to the oldest version available in eCFR... January 2017 (some months before the big reorganization. Working forward, this was still the regulation in September 2017). The "short-range" clause fell out in the October 2017 reorganization. My suspicion is that the "short-range" clause got lost during editing by an assumption that it didn't need to be stated; after all, at the UHF frequencies involved, communication is line-of-sight (to a repeater on a tower, or to effective horizon barring vegetation and buildings) and maybe a belief that linking of repeaters was inhibited by the wireline restrictions. Also, clauses about (immediate) family members remains and that sort of assumes said family members are within range that the license holder can ensure proper radio usage -- not halfway across the country on a linked system. From early 2017: In passing, I would also note that, per the definitions in the current regulations a mobile station does not constitute a "control station" with regards to the operation of a repeater... The only changes in GMRS regulations since October 2017 were two typos, and a rephrasing of the digital data transmission segment.

ProComm still lives? I ended up buying HyperAccess when ProComm Plus was no longer functional on my hardware. For all the hype (no pun intended) HyperAccess is a crude program compared to ProComm Plus (and even to 16-bit WinComm -- which had a more understandable scripting language).

Non-sequitur comment: If KAA8142 truly is the oldest extant individual GMRS license going back to 1970, and if the FCC issued sequential calls, there must not have been much activity over the 20+ years to my call... 10 thousand for the numeric, and only going from A to F -- that's about 50,000 calls issued in 20 odd years... FCC must not be using sequential calls, or it has a separate pool (since class D/CB used to get the same AAA9999 format).

Unfortunately, the only repeater near me is a grandfathered business system belonging to the Government of Grand Rapids; in my 1997 GMRS repeater guide, this repeater was publicly available only for Emergency and Traveller Assistance (and I'm pretty sure the current trustees would be shocked to find some stranger asking for assistance these days of cell-phones). The city seems to use it for parking control -- I seem to hear a lot of traffic about the pay points not accepting credit cards and/or cash, lot gates being stuck up or down, etc.

I hope you meant 1.7:1... 1:7 is frying your finals... ? Which Midland? My MXT115 is very close to the advertised rating -- but is narrowband-only; hence my awaiting the replacement Radioddity unit which I hope will display power >16W (box says 20W but manual says 18W). My newest grumble is that I ordered a GMRS-band Larsen glass-mount antenna "with PL-259" -- I expected the PL-259 to be on the coax, not in a separate zip-lock baggie and needing to be soldered to the coax [and the center connector is sized for RG-8 coax, not the skinny stuff they used on the antenna!

What tone configurations do those radios have on those channels when testing... If the repeater does not send CTCSS tones during ID, but the receiver is configured to require said tone, it won't open squelch for the ID. There is also something that some radios implement -- squelch tail elimination -- which may cut off ID response...

Interesting... My copy claims to be v2.05, but I can't find that quoted text... Or am I misinterpreting your statement (ie: the quote came from somewhere else, and is in contradiction with the CPS)?

The 65R was only $5 more, based upon my records (bought two as "incentives" for the nieces to study the license manuals I'd previously provided). However, CHIRP does list many of the Yaesu models... Including both of those mentioned...

I might be concerned that a 10W HT could be getting close to, if no already, exceeding RF exposure limits...

Unless you had all three radios with you, at the same spot (same height, same orientation, etc), when doing these "tests", the results are mostly irrelevant. UHF is heavily attenuated by moist vegetation (2W MURS units might propagate better in those woods); if the position changes enough to put a dense bush between you and the receiver it could be enough to kill reception. Heck... 4W 11m (CB) HTs might propagate better ? (ignoring skip conditions -- where a CB might hit 150 or more miles, but with no signal BETWEEN those end points -- around 1976/77 I was in the car, backyard [Kent County, MI], with a CB running; I was hearing a distress call coming in from Missouri [or other state in that vicinity]) I don't know if these low-cost radios make any attempt at a meaningful "S-meter" or just pop up a bar-graph almost as a whim... Common wisdom is that a 2 S-unit increase requires 10X power change -- that's going 5W -> 50W just for a small change on an S-meter (most S-meters display S1-S9, so we are talking, say, taking a 5W S6 signal and getting S8 with 50W).