Not the smartest move, I know. It was supposed to take only a single afternoon, but it went longer than that, as these things tend to do. Anyway, the purpose of said hole was to route coax cable from an outdoor antenna through the wall of my house and inside to my radio. This is nothing fancy (yet). The antenna is a simple VHF ground-plane vertical that I built. The radio is a certain type of 5-watt VHF/UHF handheld that shall not be named.
I cut into the drywall indoors and installed a low-voltage box:
Then I drilled through to the outside with a 1/2 inch cable bit. I realized that with UHF connectors, even thin coax wouldn’t fit through that hole, so I had to make it bigger. I got a hole saw that could cut through stucco and cut a 2-1/2" hole in the outside wall, then installed some 2" PVC conduit in it. I then added a 90-degree elbow to keep snow and rainwater from coming into the house. I weatherproofed around the edges with some waterproof silicone.
It lined up! Mostly …
I followed a common design for a ground-plane vertical antenna, where you attach metallic elements directly to a chassis-mount SO-239 connector. I used 3/32" brass rods for the vertical element and the radials. I used crimp-on ring terminals, machine screws, and bolts to attach the radials. I soldered the vertical element directly onto the center conductor of the SO-239. While I was doing this, I had some short sections of 3/32" brass rod left over, so I went ahead and cut them to the right length to build a UHF version of this antenna later. I’m pretty sure this antenna will perform fine for local UHF repeater work, although I think the radiation angle would be pretty steep compared to VHF. (Most of my local repeaters are on mountaintops, though, so that may work in my favor!)
Most antennas will work better the higher you mount them. I have a problem though: I’m surrounded on three sides by power lines. Even the middle of my backyard is overhung by the line going to my electrical service entrance. No way am I stupid enough to put up a mast anywhere near that. So I had to get creative:
My mast is just 10 feet of ESD conduit, attached with conduit straps to my fence post. 10 feet is about as tall as a mast can be before you really ought to have guy wires on it. Since my piece of conduit is only 10 feet tall, and it’s cantilevered to my fence post, it should be fine even in heavy winds. In fact, after I took this picture, I raised it up another few feet. The base of the antenna is now about level with the upstairs ceiling.
The Baofeng UV-5R, along with most other Chinese-made radios, gets a bad rap in amateur radio circles. Some people claim they create spurious emissions (I’ve never noticed any on mine), while others simply distrust anything made in China (which is fair). For what it’s worth (about $39), the UV-5R is quite a nice little radio for 2m/70cm FM. It does tend to get overwhelmed by strong signals, but you get what you pay for. The only real pain is programming in repeater offsets, PL tones, and the like. I have literally had an easier user experience while operating an early-warning radar as a missile warning crew commander. (Come to think of it, that was a UHF rig as well!)
As this is a cheap homebrew antenna being used with a cheap handheld at very low power, I’m not too concerned about damage at this point. At some time, however, I will upgrade to a more substantial base station, which will need grounding because it will likely be attached in some way to my home’s AC system. Also, best operating practices dictate that I need to provide AC and RF ground as well as make some provision for lightning protection. Lightning protection is not at the top of my list, as I don’t keep anything connected while not operating and certainly not during a storm. However, being able to operate during storms would come in handy if I ever decide to join my local SKYWARN program or ARES organization.
At some point, I’m probably going to put another ground rod in the soil and build a proper, weatherproof cable enclosure box with ground connections.
Eventually, I may decide to install something on the roof. There are commercial vertical antennas that look like vent pipes, which are supposed to be “stealthy” and unnoticeable from the street. I don’t have an HOA, so I don’t really care. If I do put something up there, it will probably be a more robust and weatherproof version of what I’ve already built.
At some point, I may also branch out into the HF bands, where “real” amateur radio is done. Even in this low part of the sunspot cycle, it’s not uncommon to make contacts with neighboring states using NVIS, or even intercontinental contacts with more traditional beam or dipole antennas. Some modes, such as CW (Morse code) are so efficient that people routinely work other continents using only a few watts. The only prohibitive thing about HF operations (other than the fact that most HF transceivers cost about as much as a house payment) is that the long wavelengths mean antennas can become rather inconveniently large. Still - part of the amateur spirit is experimentation. Building stuff is probably the part of this hobby I like the best!
Topics: radio