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For those new to radio, and aren't a complete radio dork.... yet.... 12dB SINAD is a standard measure to describe receiver sensitivity. SINAD stands for 'Signal-to-Noise-and-Distortion. This type of measurement is particularly used for analog FM receivers. It represents the point where the desired signal is 12dB stronger than the combined noise and distortion. A lower input voltage at 12dB SINAD indicates a more sensitive receiver. Receiver sensitivity is the ability of a receiver to detect weak signals. A lower input voltage (measured in microvolts or dBm) at 12dB SINAD means the receiver can detect weaker signals and still produce a usable audio output. A 12dB SINAD measurement of 0.25µV (about -118dBm, -119dBm) is pretty good. Most expensive radios are about 0.200µV (about -121dBm). I looked at that SGQ-450D duplexer specs a few minutes ago. If someone is interested in buying one, while it's only rated for 50w, it actually looks pretty good on paper. 1dB insertion loss is great and both the suppression and isolation are on par with other mobile duplexers that are 3 times the price. Again, zero personal experience with this particular device, but it looks good on paper and @LeoG hasn't thrown it in the trash yet... so those are both good signs. LOL

SOP hasn't changed, one still has to keep transmissions short to keep the enemy from triangulating your location. The Russians and Ukrainians are finding that out the hard way. Difference is you now have to worry about drones along with missiles and artillery. Signals are scrambled and most military radios use frequency hopping but the can still be located if they transmit too long.

My military radio usage was over 50 years ago, so things likely have changed a bit.

The Kraken system is like a child's toy when compared to what federal agencies and the military have. Even the equipment we had in the 90's was still better than the Kraken. We had no problems triangulating exact Iraqi positions back in 1991. And don't think for a minute that the feds are not using that kind of equipment right now. Transmitting briefly is standard SOP when using any military radio and has been for a long time. Transmit too long in a combat zone and you will get a missile or artillery rounds down your throat.

I have the Btech RT50 and it has a full spectrum GMRS duplexer. It says it's rated at .25µV at 12dB SINAD. Can't say I can prove it but it seems to receive well for the antenna and it's height. This is the replacement duplexer they sent me. The originals sensitivity was much worse than the replacement. Tuned full band.

that was the idea when using the AN/PRC-90. I just missed the AN/PRC-103 that was a pretty good improvement. There was a movie about a downed flyer. There radio discipline was pretty terrible and had they used the radio as much as they did in the movie it would have died or the flyer would have. The north Vietnamese knew what frequency to monitor.

All I got was a card and love from my family.

find a big huge round ground water tank and splatter your signal everywhere as you drive in circles around it .

It might be difficult even for a few krakens to locate FRS/GMRS radios especially if there are many signals on the same frequency. Lots of "ghost" signals that keep moving around. Maybe 3 airborn detectors triangulating with high power optical recorders might be able to do the job quickly. And I don't doubt they have such a system. But with lots of radios out in a relatively small area it might be difficult to lock on a single tranceiver and even harder to hear a single transmission in a sea of similar signals. Don't use a roger beep or any identifying transmission.

Transmit briefly and move frequently.

This! Absolutely nothing unusual about the results.

You need to look out for those krakens...

Unless your UV-5G is different from mine, it can't be changed from the radio. It requires editing in Chirp. The Shift-D set to "Off" is the same as blank in Chirp, which is the setting for simplex transmit.

And that's what I was talking about as well. Did you not see me mention FM in my post? Go back and read it again in case you missed it. And I also said that I know of three people who are using it in their dump trucks. So, someone (3 people actually) is using it.

Not Radio related but i got myself a 4Bay QNAP and 4 16TB NAS Drives. That should keep me busy for a week.

I guess I can justify my LMr400 cable as a Fathers Day gift (even if I ordered it last week).

Some Repeaters, I.e. my Hytera's, can be set in programing for IP transport basically linking them. Many Commercial repeater radios can also do this.. Although not legal in GMRS many commerical repeaters can be set in this fasshion but requires like systems.

People epoxy sheet metal to the underside of toppers all the time. And that works fine for a ground plane. Having good contact between the NMO mount and a sheet metal ground plane is what matters.

RG8X has around 86% loss over 100 feet while LMR400 has around 48% loss over 100 feet. Plus the fact that the center conductor, insulations (dielectric) and shield braid are bigger with LMR400 which helps reduce loss. @WRDJ205 your real world measurements are close to what most online coax loss calculators will show. While a j pole is not the best antenna, they work just fine. I've seen enough home made UHF j pole antennas built from solid copper wire that works well. No they won't have as much gain as other designs but nothing wrong with a J pole.

I do the same. I was just curious what bandwidth problem he thought we would be out of compliance on

It depends on the agency and what equipment they have available to them. I know that 20-30 years ago, we had equipment in the military that could triangulate a transmitter quickly. Even today's systems such as the Kraken SDR can pinpoint a transmitter fairly quickly, and two or more Krakens in different locations and the time to pinpoint a location goes down. One Kraken will get you pretty close and do so in a reasonable amount of time. 2 Krakens will do it quicker and with more precision. Three or more Krakens will be even more accurate and take less time.

The radios I have with GPS (Hytera) must be turned on in the program mode and programed how you want to xtmt/rcv GPS data. I can set GPS data to specific groups and not to other groups. If you dont have it set to send your GPS data to a specific group, nothihesng is sent, However i can set up in programing to receive GPS data from a certain group. . I have played with this but never really saw a need for it so i ignoree GPS in programing (off).. A local 4-wheeler group uses GPS in their readios to ping their locations when 4 wheeling.. Take note, Radios with GPS need to be 'like' radios as their GPS function are proprietary to the radio brand. My Hytera radios with GPS wont work with Motorola or ICOM and vis versa.

I set duplex to off on 8-14 so I can monitor them but not transmit. Should there be a legitimate reason to do so, I can pretty quickly restore the transmit capability on that frequency. It's hard to imagine a situation where that would be necessary, but I can do it if I need to. I just do all my GMRS communication on the other channels.

I dunno about everyone else, but I do it by selecting 20 kHz or 12.5 kHz when I program the radio, according to what's authorized for the frequency.

You more than likely may have a little Itty bitty wire strand shorting out to one of the connectors. Get a multi-meter and attached a probe to the center conductor and the other probe to the outside of the connector and set the meter for a continuity check and you should have either "OL" or 0.00 ohms for a perfect assembly of the connector(s). If you get any reading other than the aforementioned, you have a short. Or, your antenna is way out-of-band. Check the antenna with an antenna analyzer to determine the frequency center resonance. Who assembled the connectors? Where did you purchase thd LMR400 cable from? My first recommendation is scrap the J Pole and get a real professional grade antenna such as a Laird, Larsen, etc. and tune it accordingly.