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You know, I did miscalculate! I pulled a "Michael Bolton" (office space) and put the decimal point in the wrong spot! It's .167 dB for a 6ft jumper. a difference of 1.45 dB! That changes the total loss to just 3.08 dB. Therefore the power to the antenna is actually 43.9 dB or, 24.5W which with the antenna equates to (much better) ERP of 97.7 W. Definitely an improvement. Thanks for the catch!!

Is it possible that your calculations for losses for the 6 ft LMR400 are a tad high?

My interpretation is 50W max measured at the output of the transmitter (e.g. not at the duplexer). That said, and as I've stated in another thread, start with forgetting about watts (for the moment), and recognize that 50W is roughly +47 dB. Start subtracting all of the antenna system losses from that point. Simple (conservative) example (insert or remove your own variables as desired) Transmitter to duplexer jumper (6ft of RG142 @ 8 dB per 100ft) 0.54 dB of loss Duplexer 0.8 to 1.5 dB of insertion loss. Lets use worse case 1.5 dB of loss Duplexer to feed-line jumper (6ft of LMR400 @ 2.7dB per 100ft) 0.16 dB of loss <Corrected! 1/2 inch hardline (50 ft @1.44 dB per 100ft) 0.72 dB of loss Feed-line to antenna jumper(6ft of LMR400 @ 2.7 dB per 100ft) 0.16 dB of loss<Corrected! Total antenna network loss (one way) 3.08 dB total antenna network loss loss <Corrected! Power making it to the antenna = 43.9 dB or, 24.5 Watts (<Corrected! Antenna Gain 6 dB (note not dBi) of "gain" ERP (Effective Radiated Power) of: 49.9 dB or 97.7W.<Corrected! Also remember that the gains and losses go both directions! Thanks To @Sshannonfor catching the error! In most cases, jumpers between transmitter and receiver and duplexer are required but one need not necessarily use RG142 (Teflon) or 6ft of length. Jumpers between the duplexer and feed-line (hard line/Heliax/whatever you call it) are commonly used as to connect "hard line" directly to a duplexer. Same for the antenna to feed-line. You don't strictly have to use them/do it as I have described, but it is good practice. That said, substitute whatever numbers/components you like. In the case of the cables, use the loss specified as close to 465 Mhz as possible. Finally, the point of this was to show that one starts by using the dB (not watts). As good online calculator is: https://www.antennas.ca/calc_db_watts.htm As seen in the above (conservative) example, one can vari the losses by a few tenths of a dB to several dB by the choices one makes. In this example, the duplexer insertion loss could have been assumed to be the ideal 0.8 dB. 7/8" hardline could have been used instead of half inch, and of course the jumpers could be different cable and lengths. All of the above assumes clean, properly installed, connectors, as a bad cable connector can really ruin ones day. Hopefully this gives a better idea of how to think about antenna systems, repeater or base. Lastly, looking at cable specifications, all cable is not created equal. As popular as LMR400 seems to be with people, it's not all that great at UHF for runs over 50ft. Hard Line/Heliax can be expensive, but if one is looking to get as much power to and from the antenna...

This page has a nice listing of the various FCC designators. https://digitalfrequencysearch.com/Search/Codes.php

Hello from south Weld County.

Just retired myself here in New Braunfels. Will be setting up a vertex 7000 with either a db4 or db8 antenna in the coming few months and do some testing.

Up north in Copperas Cove, (Ft Hood) I can sometimes get Oglesby but nothing from the south. Austin has the local repeaters that don't reach far. I can sometimes get one when I visit family in Phlugerville. But it don't quite reach Round Rock. Going up to Shreveport when I lose Oglesby in about 45 minutes I start picking up Tyler, that gets me pretty close to Shreveport, But there is NOTHING there.

Plus there’s already enough discord on this Forum! ?

The Kenwood modules will do that. Plus you need a special “key loader” just to access the cryptographic module from what I’ve read.

Yes I have tested the output power on the radio previously and found power levels to be acceptable. For the sake of this post, I just hooked it up to my dummy load, confirmed input voltage was 13.8vdc and achieved 49.0 watts on 462.6500 and 47.3 watts on 467.6500, 16 watts +/- on the upper mid power setting, 8 watts +/- on the lower mid power setting and 4 watts +/- on lower setting on both of the above frequencies. BTW, do make sure that 13.8v is what the radio is seeing while transmitting, not just when idle. Michael WRHS965 KE8PLM

In my state, the criminal enhancement is written "use of a communications device", so it really does not matter if a CB, Ham, GMRS, cellphone, or paper cups are used in the commission of a crime. Also the state laws prohibit interference with police as well as commercial broadcast. So in effect, if you are running a pirate radio station they can bust you. Sent from my SM-T350 using Tapatalk

There is "amateur radio world" and then real world, with the two often being far apart. As MichaelLAX mentioned, things have changed. As for radio gear in commercial vehicles, there are other restrictions, like not being able to use radio scanners, radar detectors, and laser jamming equipment as well. Drive truck for a while and you will find that the State Patrol adds enhancements for all kinds of things that may fall under the FCC for regulation, but law enforcement for when they connect with commercial transportation. It is similar to maritime law, and the use of RF emitting equipment. Do you thin the FCC enforces licensing for marine operators of radio/radar? No, it is usually the U.S. Coast Guard that boards the vessel and checks ship and operator licenses. In my ten years offshore, I never had an FCC official check a license, it was always the Coast Guard.