Leaderboard

I use Astron SS-18 (15A continuous, 18A peak) with TK880H, bought it used off ebay. I tried Ed Fong's antenna, did not work for me well. SWR was very high. J-pole antennas need an efficient RF choke (that Ed Fong antenna lacks) to suppress common mode current, otherwise the feed cable becomes part of antenna and wreaks havoc with SWR and pattern, especially when routed close to metal mast or support. Another thing to consider is that you do not need 2m band, since your radio is TK880. Ed Fong's antenna is 5 feet long, being 2m-70cm antenna. I now use Browning BR-6140, works much better, about 2' long. Newegg still has them for $35. However, with 30miles distance, even on the 6th floor, you may need a directional antenna.

Welcome to MyGMRS To start out with, The Amps rating on the radio should always be lower than that of the power supply. The Kenwood 880H (nice choice as this is the only radio I run BTW) uses 12.8Amps when transmitting on high power. Using a 15 amp or higher power supply that delivers 12.5-13.5 volts should be fine. I use https://www.amazon.com/gp/product/B01EWG6YT8/ref=ppx_yo_dt_b_asin_title_o07_s00?ie=UTF8&psc=1 this power supply for the house "base" radio. I do get a slight hum when the fan turns on, but for the most part it works without an issue. The whine should go away if I use a choke on the power wires but I was too lazy to order them. I do not know much about Ed Fong antennas to really give you much advice on them. They seem to be custom home built antennas, which could be hit or miss. There are commercially available antennas for the 460-470 mhz range that may work better. I originally used a diamond 200U with good results, Now I use a comet 712EFC which has higher gain and is working great. One thing to note about mounting however. Keep in mind the primary use of a fire escape. You will need to run your feedline and mount the antenna in a way that would not interfere with an emergency evacuation should it ever occur. You would not believe how many times I've seen ham radio operators and CB'rs just throw the feedline across the fire escape completely blocking it should people need to evacuate. Or they mount Yagi antennas (a directional antenna) that block the escape. When I talk to some of them it seems their concern was that they could escape and the hell with the rest. They just don't realize they could be charged if someone is hurt or killed should a fire break out. So be sure to take great care with that for everyones safety!

Sorry. That question is above my pay grade as I don't own that radio. Although, based on the GMRSV1 I would guess that there are only a specific number of channels that can be programmed for Tx & Rx. I am sure @marcspaz or someone else with hands on experience will have the answer.

Well, looking at the specs on this radio from BTech, it will Tx and Rx from 136 to 174 on VHF. Since MURS runs from 151.82 to 154.60, it would be covered. Note however, MURS radios must be certified (Part95-J) and this radio is only certified under Part-15. See the official FCC certification report for more information. To answer your second question, If you look at page 22 in the manual (also available on the BTech web site) it looks like Receive and Transmit CTCSS are set independently. Also note: while they proudly claim BTECH Radios are Designed in the USA. while it is not, per-se a problem, the radio is most certainly not manufactured in the USA. Also, it is very likely the term designed refers to the software/firmware and not the radio hardware. And... If you are not already familiar with miklor.com, you should check them out. I am not convinced their reviews are impartial. But, they do provide good information and are an excellent resource. They have a review of the UV-50X2 from 2017.