BoxCar

When reading the rules looking for specific information, you need to pay attention to any other rule or section listed in the footnotes as well. The FCC uses a lot of cross references in putting their rules and regulations together. After all, they are lawyers first.

I have a Land Rover and use a trunk lip mount on the hood,

It sounds as if you will be in the number of units limitation on the license. Send me the call sign by private message and I'll look at the license class as there may be additional restrictions. Under part 90.35, the authorized frequency coordinators all operate with the assumption that frequencies are shared and are not exclusive. The call sign will also tell me if they are on itinerant channels or regular business band channels. Itinerant channels are primarily used for short term messaging and lower power.

It sounds as if the theater has licensed channels in the Business commercial spectrum. Adding radios will depend on the number of units authorized from the application and the class of the licensed operation. You can't always just add more radios to a licensed frequency.

There are no rules regarding what you use to receive with other than it carry an FCC approval. The transmitter though is different and needs type acceptance for the task.

Michael, I'm a former NATIONAL frequency coordinator for Parts 90.20 and was a member of both the Land Mobile Communications Council and the Public Safety Communications Councils besides being a member of the FCC's Communications Information Security and Reliability Federal Advisory panel. I did part 90.35 and 101 coordination. I have written petitions to the FCC for rule changes and had them implemented. One petition initiated the first rule change in 35 years. I was an instrumental part of obtaining the Band 14 allocation at 800 MHZ among other items in my career. Now, what have you done that provides you with your qualifications?

Just because the rules do not say you cannot do something, they also don't say you can either. By convention, UHF repeater pairs are 5 MHz apart for uniformity. If you use a non-standard split you need to monitor both input frequencies to prevent interference to the other users. Rules DO state you are to avoid causing harmful interference to others.

You will get about 4X output from the antenna over the power level after coax & SWR loses.

Michael, as you do suffer from Valley Fever and its associated atrophy of higher cognitive functions, Goretex tried to politely state the issue isn't what others state, it's you. You are the one constantly bringing extraneous clutter to questions and possible solutions through the use of non-certified equipment, restating steps just stated by others earlier in the thread and then attempting to dismiss criticisms through your use of very poorly constructed sarcasm or snide comments. I do agree that you have provided some assistance in instances but it is your constant "need to input" on any topic which is the primary issue. In other words, you are not the best, most accurate or final authority on the questions raised by others. Stop trying to monopolize the forum.

Yes, more power does mean better penetration, but again it's another relative thingy. It depends on what you are trying to penetrate and the density of the obstruction. As far as bouncing (or reflecting) the signal off rocks like mountain sides or canyon walls, it's again the material used as the reflector. So more power may boost the signal from a poor, but marginal surface, at the levels we're using it's negligible.

Blaise, You're not the only one to need a fact checker. Try any of the Talking Heads or denizens slinking around Capitol Hill!

It may also be a flaw in the radio's design where that particular code causes a harmonic in a different part of the radio.

Another point to consider, antenna orientation. If your GF points her antenna to you, the signal will also drop because antennas radiate from the middle, not the end.

Mike, Your radio needs to transmit a tone to wake up the receiver on the repeater. In your configuration for that channel, set the transmit tone to the same value shown in the repeater's listing. You do not need a receive tone.

My thought as well, it's overpriced for what's there. The one point in their favor appears to be the installation instructions. IMO you can probably do with a 20 to 25W radio on the trails and for most travel needs. the extra power from a 45W UHF radio buys you maybe an additional mile of coverage.

The "custom" channels allow you to store various configurations of the authorized channels such as those using tones for '"privacy."

One more question; how are you testing the radio?

Here are plans for a GMRS J-Pole that is about 18" in total length built from a piece of 300 ohm TV twin lead. It can be put into a PVC stub and hidden on the roof as a new vent pipe. J-Pole Emergency Flexible Antenna (fiu.edu)

Laird BB-4505cr Manufacturer TE Connectivity Info Ground Plane Required Frequency (MHz) 450 - 470 MHz Product Narrative TE Connectivity ongoing commitment to refinement in mechanical and electrical design has resulted in the release of their latest product, the mobile coil antenna with an elastomer spring. The new elastomer spring provides increased flexibility, better shape retention, and eliminates electronic noise & road noise compared to stainless steel springs. The mobile coil antennas will continue to maintain all of the features that make them unique, such as stainless steel whips, housings constructed with ABS material injection molded around a solid brass insert, and gold plated push pin contacts. Together, the mobile coil antenna and elastomer spring, make TE Connectivity the obvious choice for quality and long lasting value for demanding mobile radio communications. Gain (dBi) 5 db Maximum Power (Watts) 200 Whip Length (In.) 34" Whip Material Stainless steel Bandwidth 20 MHz Spring Incl. Yes Color Black Base w/ Black Whip Mount Type Order NMO Type Mount Separately

Good question but for commercial/public safety grade repeaters the output level is at the antenna connection. These heavy duty units are also built to put out their rated power for hours at a time unlike the hobbyist grade units like the Retevis.

If you are playing with parasitic radiators (metal reflectors) then the distance between the antenna and the reflector is key. The distance between the two determines if the reflected wave adds or subtracts from the primary.

I'm still waiting for them to ship my maggy mount for my aluminum car....

But you don't know if it was BS or not even though the OP clarified there was a newspaper report. There is a 50/50 chance reports of an FCC investigation being in progress are true as, like your local PD, they don't make public reports of every investigation they undertake.

No, it won't be in the database as no action was taken. An investigation is just that, someone looking into something. You may find emails talking about investigations, but those require a FOIA petition to access.

The cost and frustration in attempting to use two handheld radios as a repeater is about 10 times the cost of the Retevis system.