marcspaz

Diamond X200a.

I thought about that, too. One of the biggest things stopping me is there is no information on how big the center hole is. I need something that accommodates a 2" mast base. I can always reach out to the sellers. Just haven't yet.

I was thinking about getting one of the tripods with a 8 foot base and 5 feet high... but $200 vs the $25 for the 3 footer I have. Man.

I don't think it's going to work, regardless of where the antenna is in the house. Around here my handheld only gets out about 1 mile on average. On a great day, I'll have splashy comms at about 2.5 miles... but that is purely outdoors with minimal obstructions or elevation changes. The reason the repeater is working for you is because its using a great antenna on the roof of a building that is close to 100' above the ground. Have you done any testing yet?

I have a few questions. Are you trying to get coverage from building to building, specifically or are you looking to get coverage on the ride to/from home? Is she using a mobile or handheld? If she is using a handheld in he building, what floor is she on? Where she works... are there buildings visually blocking the path to the house? What is the elevation of the two locations. I live in Woodbridge and commute to DC on occasion. The RF noise levels are very high in our area and the radically changing elevations as we make our way north/south makes continuous comms almost impossible on UHF while driving. Point to point fixed station requires elevation and good antenna placement.

That's a good idea. It is volunteer work and it does get expensive. I may go that route if needed. I was going to use the spikes to stop sliding side to side, but I have some notched 10 lb weights I was going to drop on each foot, to help prevent tipping. The board idea sounds good, but I will lose the ability to easily transport and setup since I am using an SUV. If I had a pickup, I would just toss it in the back.

I've seen this before. I like them, but have had trouble finding one at a reasonable price. The one I have right now is supposed to be bolted/screwed down to a building's roof. So, the footprint is very small. It's not ideal for tall setups.

Today, I put together a new portable repeater antenna setup together. I do a lot of work with Amateur Radio Emergency Service. Often, we need a repeater setup so our people can run around with HT's and still be able to communicate direct with everyone. The antenna is setup for 2m, 70cm and GMRS. In all services, the SWR is 1.2:1 or better. It's sitting on top of a fiberglass mast. The total height is 47 feet from the ground to the top of the antenna. The bottom of the antenna is 40' from the ground. My son Nick is next to it to use as a reference. I tested it out on 2m. Full quiet to another station 40 miles away, with only 5 watts. I'm pretty happy with that. On 70cm and GMRS, I was full quiet to a repeater 22 miles away with just 2 watts. I am pretty happy with this setup. I am going to be doing a training drill on March 28. We'll see how it goes. http://fiveguysracing.com/marc/HAM-GMRS/Pot_2m-440_Repeater_Antenna_2.jpg http://fiveguysracing.com/marc/HAM-GMRS/Pot_2m-440_Repeater_Antenna_3.jpg

Most coax doesn't have a minimum or minimum frequency cutoff. Almost all commercially available cable is usable from 0.3MHz to 3GHz. Some higher. Coax cable attenuation ratings are tested at 750MHz, for instance. The big things to be aware of is the conductor thickness for the power levels (not too thin), the impedance (which is not frequency specific), and the length of the cable. Most people have no idea how much matching the coax length to the wavelength (or half-wave length) impacts performance. However, most of the stuff we do in VHF and UHF, unless you are doing really high power (1,000-1,500 watts), the performance gain is negligible. It's most noticeable at the bottom end of VHF and lower. With GMRS, as long as the impedance is correct and you don't have some crazy types or numbers of adapters, you should be okay.

I laughed so loud I woke my wife up. A friend of mine was going to put one on his Range Rover. I told him to just give me the $10 and sell his radio, because the end result would be the same, only I will at least be able to get a cheeseburger and a coke. LOL

I wrote a couple of opinions about it in the reviews forum. Take a look. Not my cup of tea, performance wise. Lots of nice features, though.

You're welcome. Yes... the antenna works great for me on GMRS. At the power levels GMRS works at, any SWR 2.0 or less, you are safe. 1.5 or better, you should get good performance with minimal power loss.

http://fiveguysracing.com/marc/HAM-GMRS/X50a_462.jpg http://fiveguysracing.com/marc/HAM-GMRS/X50a_467.jpg

I have a Diamond X50a on the roof of my house. It's been up there on the original install for close to 20 years and it runs great. I'll hook up the antenna analyzer when I get home so you can see what it does on GMRS. I have a few Comet antennas for the mobile radios, but not for a base. Can't help there.

Welcome! There is a lot of great information here, and some very talented operators that are here that are field techs and engineers for their career. If I may... if you want to talk about the pros and cons of each service as it relates to offroading in this thread, I would be happy to give you some input. I'm sure others will too. I go wheeling out in the mountains of WV, VA and PA pretty regularly, and have some pretty capable setups. I understand about the conversations heard on the CB. I was on it today and its not kid friendly if you are anywhere near a major highway. LOL

That Tram is a monster antenna. That should do the trick. The ground plane kit is going to be a huge improvement on your side too. Good luck. Looking forward to hearing back with the results.

Wow... what a hot mess that thread turned into. Through my life, I have always heard and believed that purpose of Amateur Radio and what has become the Public Radio Service is to promote goodwill and forward the science. Those folks don't seem to be interested in anything of the sort.

I go straight to the battery because I have an insane amount of voltage drop on transmit when I use the factory common ground and B+ bus bar. Like... 14.6v in standby dropping to 12.4v (sometimes less) on transmit. Going direct to the battery, even with my 200w amp, I never see more than a 0.3v drop.

Where you been man? Haven't even seen you much on FB. Hope all is well. Depends on the wire gauge. What size it is?

It's very common in expensive and/or high power Ham radio gear (100w+) to protect the vehicle. Most radio manufacturers fuse the B+ side at the battery so if the B+ power lead gets shorted to ground, your vehicle doesn't burn down. Some also fuse the ground wire to prevent fires. This is mostly a risk for vehicles with a separate frame and body. In a vehicle, the body is typically the ground for most electronics in the vehicle. If the body has a poor ground or the chassis ground is broken all together and the radio ground lead gets shorted to the body somewhere, all of the electronics grounded to the body will then try to use that ground wire as the primary ground. Obviously the positive fuses for all the other circuits won't blow because the current on the B+ side is whats expected. The ground wire is sized for the radio and not all of your onboard electronics. So, to stop the negative lead from burning the car down, it gets fused at the battery side for the same reason as the positive lead.

Ah... got you. I thought you had a Midland radio, for some reason. I have zero experience with those. The Midland antennas are not great, unfortunately.

He brings up a good point. The Gen 1 MXT400's were problematic. My Gen 1 broke the first day I had it. It was deaf and power was weak. It dropped off 100% after a few minutes of use. most people reported all kinds of issues with the gen 1's drifting and not being able to get proper audio into repeaters. I had three Gen 2 MXT400's. All of them worked great. I get 5+ miles mobile to mobile (depending on terrain), I am full quiet into a repeater that is 22 miles from my house. Do your mics have loops for hanging or button style to go on a 2 prong hook?

Kenwood and Moto are good... but Vertex Standard? On their own, under Moto or Yaesu, I was never a fan. I still have one of their tuners and its better at creating RFI than a proper LC network. LOL He is using a Midland mobile mag mount antenna in the house. Regardless of the radio in use, I am fairly confident the lack of a proper antenna is an issue.

The X50a is pre-tuned. There is nothing to adjust. For me it just worked well for GMRS as well as 2m and 440. The CR8900's are mobile... which I did tune manually. I would avoid trying to use them at home, though.

I have no idea how, but I have talked to a couple of people using the Midland 6db gain antennas on the mag mount, stuck to cookie sheets and they sound great. I have never gotten that to work with any service. I am using Comet and Diamond antennas for most of my mobiles. I only have one Midland antenna left, and its going bye-bye very soon. While the midland antenna seems to work okay for me RF performance wise, after less than a year, 2 of the 3 I have broke mechanically. One, the bottom section snapped off, requiring the antenna to be re-soldered and glued back together (ended up in the trash later anyway). A second one, the center loading coil broke in half and the top section of the antenna disappeared while cruising down the highway. The last one I have left has only seen about 2,000 miles in the wind and it looks like a boomerang. The metal whip sections are not standing up to highway speed winds. So, yea... they are junk.