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Unless I misread the NEC and other sources, the tower should have its own ground and be bonded to the service ground. This is correct. Steve did a good job of expelling things

Let’s disregard lightning protection for a few minutes and just talk about bonding to your house service ground. Your tower is sort of grounded. We all agree with that I think. It’s embedded in an imperfect conductor, concrete, at the bottom. To improve the grounding a ground wire runs from each leg of the tower to a ground rod. But any two separate ground rods are almost always at different potentials. Whenever you have different potentials between two points in a circuit you will have electric currents flowing from one point to the other. So, the three or four legs of the tower are bonded together using a material that is more conductive than the tower itself. Otherwise you have current flowing between the legs of your tower. If current flows between the legs of your tower over time the metal of the tower will corrode. Bonding between the three or four legs provides an easier path for the current to flow which keeps the legs all at the same potential. In addition your antenna mount is certainly connected electrically to your tower and your coax shield is connected to your antenna mount. Your coax shield then runs to your radio. If you have a watt meter, amplifier, or any other device between your radio and your antenna, they are all connected serially via the coax shield. Their metal cases are all connected to the coax shield. So all of the devices in your shack are connected together via the coax shield. If a power surge comes through the shield (static, lightning, unicorn farts, whatever) it is going to cause current to flow through your equipment because that’s the most direct path. By bonding the chassis of all those devices to a single point, we provide a much better path that doesn’t flow through those devices. So that’s why we use a single point ground. But remember, that single point ground is connected to ground at the tower. You power your radio with a power supply that’s plugged into your house power. Its case is connected to the ground wire in the outlet which runs back to the service panel where it’s bonded to the service ground for the utility power coming into your house. It has to be because NEC says so. So let’s say you don’t have your single point ground bonded to your service ground. You reach out to touch your radio and at the same time your brush your other hand on the power supply. The potential of your tower ground, which is what your one hand is touching, is probably different than the potential of the service ground, which is what your other hand is feeling. And it’s DC. Your heart can be stopped by as little as 1/10 of an ampere. So you die. So we bond the tower ground to the utility ground to ensure they are at the same potential and save your life. Also with fewer ground currents in the shack we hear less noise.

What happened to the Winslow repeater in NW Arkansas? It doesn't come up on the gmrs map and it does not seem to work for me anymore.

I’m thinking I’m going to build a repeater. I’m making a shopping list. I want to use two Kenwood tk-8180 radios and a mobile Celwave 633-6a-2 duplexer. I keep seeing images of people using what looks like rg400 coax from the radios to the duplexer. I used lmr400uf ultra flex from DX Engineering to connect my base station and I have some left over. But the lmr400uf is still stiff for such a small distance from radio to duplexer. If I use a smaller coax like the rg400 vs the lmr400uf will it make that much of a difference? thank you!

So, a home antenna tower shouldn't have it's own ground? Just bond to house ground?

I'm not following you. What does that have to do with lightning protection? What kinds of problems will it cause? To be clear, I'm not being confrontational. I'm really trying to understand this.

To prevent electrical noise being transferred from one system into the other system. You are drawing power from one electrical system thus you should be using only one grounding system. If you have two earth grounding points then you have two grounding systems and that will cause problems.

Today, after much research, I programmed my new AR-152 radio using Chirp. I used the UV5-XP profile because it was recommended in another forum, is similar to what the manufacturer recommends, and features three power-level settings. After downloading and saving the factory settings, I uploaded my list of frequencies to the AR-152 using the UV5XP profile. I did not mess with frequency range or any advanced settings. So far I have only modified a few basic settings like muting the beep and voice. As measured by the Farsometer, the transmit power levels remained the same before and after programming with Chirp. I am still testing, but so far the radio appears to function as designed. Pre-Chirp: Freq. 155.500 H: 8.2 watts, M: 6.3 watts, L: 2.08 watts Freq. 438.500 H: 9.2 watts, M: 5.8 watts, L: 2.4 watts After Chirp: Freq. 155.500 H: 8.2 watts, M: 6.3 watts, L: 2.15 watts Freq. 438.500 H: 9.3 watts, M: 5.9 watts, L: 2.5 watts

Correct - Because Commercial Sites Don't Have A House - They Have A Structure Or A Cabinet For Equipment. The Structure Or Cabinet Requires Proper Bonding - For Single Point Grounding - To Avoid A Ground Potential Difference.

Hello Group! Here is a quick repeater system update! 6/28/25 SGA-575 is on the air! New updated repeater is in and being readied to be installed in the near future. Also antenna crew is being scheduled to replace the existing antenna with one that has higher gain. SGA-600 is on the air! Intermittent noise issues....Replacement duplexers have been received and tuned. Scheduling date to install them. SGA-650 is NOT on the air! Down due to hurricane Helene tower being destroyed. New site has been located and equipment is being ordered. Tower crew to be scheduled for work. No ETA at this time. SGA-700 is on the air! No issues noted at this time. Thanks, Scott Haner - SYSOP WRFS362

That was my logic, hence my confusion at the recommendation to do that.

Yes, but commercial tower sites don't then bond the ground to a house ground. What I'm trying to figure out is why almost every article or video I find recommends doing that.

The actual ground (i.e., dirt) can be a conductor of lightning that hits nearby, especially wet ground in a thunderstorm. By installing grounding wires, you may be increasing potential of that getting to your electronic devices inside. For ordinary folks, disconnecting the devices from the AC and antenna lines is the best option.

It's Called Single Point Grounding. Reason - To Eliminate A Potential Difference Between Having (2) Separate Grounding Systems. Single Point Grounding Is Done On All Commercial Tower Sites.

You answered your own question by keeping PROPER grounding outside so there's no need to do any grounding inside the house.

I'm sorry, but I don't understand how that relates to my question. Please elaborate.

All radio related grounding should be done with 500MCM cable. End of story.

What is the logic behind bonding your lightning ground to the house ground? Lightning always wants to go to the earth, so grounding your antenna and coax makes sense. You give the lightning an easy path to the earth, and hopefully it will take it. I also understand why it's recommended that you bond the common ground for your equipment to the house ground. The powered equipment is part of the same circuit as all the other electrical equipment in the house and you want to keep it at the same potential. However, I don't follow the reasoning of bonding the two together. It seems to me that the most logical solution for protecting against lightning is to give the electrical buildup a way to get to the earth without directing it into your house; i.e., a lightning ground separate from the equipment ground. Yet everything I read recommends bonding the lightning ground to the house ground, so there must be some reason that I don't understand.

Awesome, thanks for that information. I will definitely be taking that into consideration. I'm just trying to get something up and going for the meantime as I build the setup I want when I have the time to do it.

I want to set up the antenna temporarily in the joists until I can get the long term setup built and in place. I don't get a lot of free time due to work, kids etc. so I was going to do the joist mount as a down and dirty temporary solution as I built the antenna setup I really want. If I do mount the temporary setup outside, I want to make sure it is properly grounded and bonded. I work as an industrial controls electrician and I've seen how lightning strikes, even indirect ones, can completely destroy communications systems.

I don't know why the quote box attributed that line to you. Probably my bad though.

Not sure about your station plans. If you "... pop a hole to the outside of my house for a base station antenna to be mounted at the roof but I need to locate a good mounting point, penetration point, and pathway to my base station setup.' then how does the joists in the basement come into play? An antenna that close to obstructions can present a higher SWR than the radio might like. Up vertically, in the clear, would be the best bet, other wise there can be many compromises. Using brackets to the side of the house should get you in the clear; I would prefer that to actually mounting it to the roof. (on a tripod or rooftop tower.) TV antennas have/had been mounted on brackets that way for years.

When choosing between horizontal and vertical polarization for GMRS antennas, vertical polarization is generally preferred. This is because GMRS is primarily a mobile and portable radio service, and most mobile and portable antennas are vertically polarized. Therefore, repeaters are also typically equipped with vertically polarized antennas. Using a horizontally polarized antenna to communicate with vertically polarized antennas on repeaters, mobiles, and portables can result in a loss of signal. This is due to the mismatch in polarization, which can lead to reduced signal strength and potentially poor communication quality. If you are considering a horizontally polarized antenna, it would be most effective if all other stations you are communicating with also use horizontal polarization, which is more common in fixed links rather than in mobile or portable setups. In a line-of-sight situation with a direct, unobstructed path to the repeater antenna, a horizontally polarized antenna might offer more gain. However, this potential gain must be weighed against the likelihood of encountering mixed polarization in the field, which can negate any benefits. For general GMRS use, sticking with a vertically polarized setup is recommended to ensure compatibility and optimal performance with the existing infrastructure and other users' equipment. If you are setting up a base station and are concerned about antenna polarization, it is also important to consider the height and placement of the antenna. Antenna height is often more critical than the length or type of antenna used. A higher antenna can provide better coverage and signal strength, which can be more beneficial than the polarization type in many scenarios.

As a preface, I should mention that I am rather green in the whole GMRS scene but I have some experience from my years in the emergency services, so I understand the bare basics. I only ever had to set up mobile systems and that was few and far between. I've maintained quite a few emergency vehicles and did a full upfit on one which turned out beautifully. For my long term setup, I want to pop a hole to the outside of my house for a base station antenna to be mounted at the roof but I need to locate a good mounting point, penetration point, and pathway to my base station setup. I also want to install the cable in conduit to protect it if i have to run most of it externally, intall a proper grounding system for lightning protection and tie it to my data grounding system I built to ensure equal potential. This being said, I have a lot of work ahead of me for that Install. I would like to temporarily set up my base station and mount my antenna inside the basement up between the floor joists near my base station location. I'm looking at horizontal mounting to keep it out of the way and looking at a ground plane. Here is a list of supplies I have so far. I plan to use a different antenna when I mount it externally on the roof. -AnyTone AT-5888UV Mobile Transceiver -BTECH RPS-30M 30 Amp Compact Regulated Bench Power Supply -Nagoya GPK-01 (21" Radials) NMO Mount Ground Plane Kit -Midland - MXTA26 MicroMobile 6DB Gain Whip Antenna -PL259 UHF Coax Cable My main question is with the antenna orientation and ground plane. The antenna mounted vertically would be ideal but I just don't have anywhere to mount it besides in the floor joists. If I mount it horizontally with the whip pointing toward the exterior butt plate of the wall, will I get decent signal reception? I should also note that some of the stuff I bought with intentions of reusing it on a mobile setup once I get the base station situated. I wanted to make sure that what I bought for the temporary solution wouldn't go to waste.

From my experience you'll have neighbors who will jump on board immediately after a motivating event. Others take more than one event but will come around. And some who won't ever get involved, but certainly take advantage of your connected group. It's hard to keep everyone involved active as the motivating event fades from memory. Sadly, so far, we've had enough events that folks have stayed involved. From the initial home invasion to somewhat frequent medical emergencies.