Need a bigger pie pan as that is your ground plane. A small cookie sheet or pizza pan would be better. Ace Hardware sells small sheets of steel and you need one about 12" or more per side.
Not if it is capable of operation outside its certification. Monitoring MURS is not a violation but enabling transmission is outside the certification for the radio. You have modified the radio so it is no longer compliant with its certified use. You are operating under Part 15 rules using a modified Part 95 radio.
Adding MURS frequencies moved your radio from being a GMRS unit to an uncertified intentional radiator operating outside its designated purpose. You can't have your Part 95(e) and eat it too!
Wireline refers to two locations connected by a physical, terrestrial connection. Telephone networks communicate between points using a physical hard-wired connection hence the term wireline. The term can also trace its beginnings back to the early days of telegraphy where physical wires connected each station to the other. The term predates radio and its modern equivalent wireless.
The operative word is temporary as these types of poles will collapse or fold with any decent load caused by wind blowing against your antenna. If the antenna is going to be on your house, look at either roof mounted tripods or gable mounts as used on satellite dishes. These are more permanent mounts for antennas that are better than the J-Poles.
The cost of the antenna also includes the mast/mount and feedline. Start with your budget and then the feedline needed before deciding on the mast and mount. That will tell you what's left for the antenna.
The light bar may generate a tremendous amount of RF from the LEDs rendering your installation worthless. This will be particularly true with the ones from offshore that are not FCC certified'
I can agree with your statement with emphasis on the word should. There are too many variables regarding antennas to make the statement true in all instances.
The PSTN, or telephone network, has evolved over the past 30 years to where it is also a packet switched network as it changes its transport medium from copper to fiber. The changes began before the breakup of the Bell network with the Long Lines or long distance service replacing microwave links with fiber. This has been going on since the late 70's. I doubt if there are any microwave links carrying interstate traffic anymore. There may be a few links remaining for local and intrastate but even local service is being converted to fiber with the copper retirement programs going on in many of the companies.
The frequencies also need to be reversed on the repeater. A repeater listens on the high frequency and transmits on the lower frequency. Your radio is programmed High out, Low in; just the opposite of the repeater.
Yes, and I answered the exact question asked. The code goes in the memory for channel 17rp. The radio make and model have no bearing on which memory gets the code.
You are correct in thinking the 5/8 would have a better radiation angle but look into using a cookie sheet or piece of sheet steel from Ace Hardware for the magnet mount. Put it on top of a bookcase or shelving unit in a closet for added height. Height is even more important than the radiation angle.
The choice for a repeater antenna depends on how deep your pocketbook is. The better antennas are all large and have gain measured in dBd. DBd gain is a multiplier over the power radiated from your unity gain J-pole. If a gain figure is published using dBi, subtract 2.1 from the figure to get the true gain of the antenna. So, a 2.1 gain dBi antenna actually has zero or no gain over a half wave dipole. Considered as the best all-round antenna is the CommScope DB 420-B radiating over 8 times more power than its input.
In this discussion the radio make isn't important as the OP has told us he has two choices, channel 17 or 17rp. The channel needing a code is 17rp, the repeater channel rather than the simplex channel, 17.
The best antennas for bandwidth are the ones designed for single band, commercial use. Dual and tri-band antennas are all compromises made to tweak the antenna to work acceptably.
You only need the code in receive if there is interference from another repeater on the same channel. Ussing no code for receive means you will hear all transmissions on that frequency. It's always better to leave the code out of receive except for specific instances with co-channel traffic.