marcspaz

Red lighting mean you owe the FCC money. That can stop your application process. You will probably have to call them.

I can't test mine against the chart above anytime soon. I am disabled and can't get on the roof. I have to hire a climber. During my original test, when I measured the 1.5 or 1.6 (don't recall exactly), it was on a tripod with a 3 foot patch cable. The feed line should not be an issue in that case. If we calculate for the masking of 100 feet of the LMR400 I am testing on now, with the 1.17:1 I am measuring, that would still only be 1.4:1 unmasked VSWR, which is still good and agrees (close enough) to what I measured while it was on the ground. Not sure what to say. My x200 is in the garage and close in performance. While its not the same antenna, it may shed some light for me. I may test it today or tomorrow while on the tripod.

@WROZ250... I appreciate the detailed response. No arguments here. I have to be honest, this is my first x300 and I don't know if this is normal/typical performance. I assumed it was since it's a stacked array with induction coils and a capacitance hat inside the tube to give e it flexibility and hight gain. I do find it odd that it's both wide in range and high gain. Normally I've seen a sacrifice in bandwidth as gain increased. I use to use an x50. It was fine for portable ops (which is what I used it for) but wasn't great. I went with an x200 for portable and an x300 for the house... mostly because I an switching the x300 between 3 different radios and seemed to have the best performance where I expected to use it.

Can I see a picture of the mount and rack?

@WROZ250 Did you look at my images? I tested the X300 on a tripod at 8' with a 3 foot patch cable before I put it on the roof. It was 1.6:1 or better on every GMRS channel. 30 feet off the ground with a ground strap, its even better. The X300 has much wider coverage on UHF than VHF. I will say that if @tweiss3 truly has a 2.5:1 SWR on the 462 frequencies, I would say something is wrong, other than antenna choice.

Here are the readings on my X300 with a 30' run of LMR400. Not getting on the roof anytime soon. Did you add a ground strap to the base of the antenna? I have a run of 6 gauge going to a ground rod. May be the difference.

I'm courious about the SWR on the x300. I have the x300 repeater antenna mounted at my house. The extra height and gain contribute to extending the coverage area. I got an additional 5 miles but switching from the 200 to the 300. I'm going to go grab my analyzer and checking my SWR. You my have something wrong on your end. Last I checked, my SWR was 1.5 or 1.6.

Everything that adds height about the ground (in this case the mount itself) adds height/length to the antenna, thus impacting SWR.

You're not talking to anyone with a bubble pack radio from car to car unless you can see them anyway. Not sure a $10-$20 radio not having a scan function is a real concern in this situation.

For spring protection when offroad, I use the Comet SBB-1. Its basically a taller rubber-ducky antenna good for 60w. 100% flexable and works great for MURS, 2m, 70cm, and GMRS.

There is no "limit" on antenna height from a GMRS rule perspective. If you have a 1,500 tower, from an FCC rule perspective, you are good. Now, there are registration and notification requirements for antennas near airports and for antennas over 200 feet. However, as long as there is no safety or environmental impact, they will simply process the notice/registration into the official record. There could be state, county or local restrictions, etc. If you are dealing with an HOA... have fun getting an antenna up at all. It's always a fight.

@fremont I am in agreement with @mbrun. If the cable is NOT connected to the radio nor an antenna, and you measure between the center lead of the NMO and ground (and/or the antenna mount bracket), and it shows <1 ohm, then you have a dead short in the cable or the mount. Take the coax completely off the mount and see if the short between the center lead and the outside of the cable still exist. If it does, you need a new cable. If it doesn't, its the mount, and I would still be very suspicious of the nylon isolator.

@wrop206... LOL true story.

Hmm.. odd, why did you vote down my response? You don't believe adding the spring can cause problems? I noticed @WRAM370 gave the same advice and you agreed to try removing it.

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@DanW Yeah, like I mentioned earlier (today? don't remember. LOL) I don't think 20 is the right answer either. I really hope it gets more popular, though.

LOL... Point taken. The total population in and around the Line A is significant, for sure. I don't know if call signs start with any other letter than W, but per the FCC there are only 126,153 GMRS licenses that start with W. Seems about right since there are 842,408 actively licensed Amateurs, and ham radio is much more popular.

Oh, man! I missed the spring part. Adjusting the antenna length a couple of millimeters can throw off the SWR. Adding a 4 or 5 inch spring will definitely through it off.

There is a nylon spacer between the mount and the center feed on the 3/8x24. Make sure its aligned correctly and not crushed. If you have an ohm meter, disconnect the cable from the radio and the antenna from the mount and see if the center lead is shorted to ground.

No, I am not saying that 79 million people live above Line A. They would be packed ridiculously tight. What I am saying is, the total population of the northern states that Line A is present in, per the Census Bureau, is about 79,633,000+. That is enough people whom driving to or north of Line A is a distinct possibility, that they should be considered in a standardization proposal.

No, I'm sorry.. That is not what I am trying to say. What I mean is, none of your measurements are in agreement with one another.. Therefore I do not trust the 40 W reading. I believe that either you need to calibrate your watt meter, your amp meter, your volt meter, some combination of the three or all three.

@WROZ437... you are experiencing exactly what I would hope to avoid. Finding something other than 20 for "over the road simplex" would work much better in many cases. Maybe, there is no single channel as answer. OffRoaderX does have some entertaining content. Being a Jeep enthusiast, I love watching offroad videos.

Something I was thinking about with regard to Line A... 90% of the US population lives on the the US borders and coast lines. ~79,633,000 people live on the northern border. That means that Line A has the potential to impact communications for more than 24% of the people in the lower 48 states. As much as I like the idea of picking a channel, a channel other than 20 to avoid conflict with potential ORI type repeaters, a solution that potentially excludes almost one quarter of the population doesn't seem like a solution at all, IMHO. In fact, I would be more prone to encourage people to use 20 over 19, since many repeaters have light traffic and operators are supposed to be mindful of not causing interference as part of their license agreement, anyway. I don't know the right answer. Just thinking.

The meter should have come with a ground plate for testing HT's with antennas. I though the meter was at the base of the antenna. If you are 4 feet away, especially if the meter is inside the vehicle, that should be plenty of distance and shielding.

The number one rule of emergency communications is, the command center should never be in the affected area. If you are in the affected area, you need to have a radio relay system established to get the message to the appropriate logistics or CnC staffer inside or outside the affected area, to send help. So, if you are outside the impacted area, get the person's name, what the emergency is, where they are (to the best they can say). Basically the 5 W's. And then you or someone right next to you calls 911 and relays that information. If you are in the affected area, you gather all of the aforementioned information and then relay it through whatever stations needed or direct to CnC, logistics, or whatever unit has been established to respond to the type of emergency being experienced. If you are at an event that is just starting, you will likely be relaying that information directly to Incident Command. Yes! Exactly! Both fantastic radios. I am partial to the Icom, but you can't go wrong with either.