Approximately 53% of the stations joining the net in the last 6 months transmitted their check-in using a handheld radio. I appreciate the portability and convenience of a handheld radio and I take one with me every day. With so many options available it is easy to find what you are looking for - a portable radio with features similar to a higher power mobile, or an affordable radio for voice communications.
When used with the repeaters dotting the mountain peaks in the region, a handheld radio is a great communication tool. For example, if you can reach the BARC Pisgah repeater connected to the Intermountain Intertie, you can talk to stations hundreds of miles away.
There are limitations to handheld radios, however, especially in simplex communication. Your range with a handheld radio is affected by the frequency band in use, the power output of the battery and obstructions between stations.
Along with buildings and terrain, another obstruction is the curvature of the earth. Lets say 2 operators are using handheld radios with antennas positioned vertically at 6 feet above the ground. If there were no other obstructions than the curvature of the earth, the effective range of communication would be about 6 miles.
With these limitations in mind, tonight we will discuss a few considerations for communications via handheld radio.
First, make sure you are operating on the highest power setting of your radio. It won’t overcome the ultimate obstruction, the horizon point, but the stronger the signal strength, the more it can withstand weakening when it passes through obstacles such as buildings. This does shorten the operating time before your battery is discharged, so take that into account. Extra batteries or a higher amp hour battery will keep you on the air longer.
One of the easiest ways to extend your range is by focusing on your antenna. The effective horizon operating distance referenced earlier is based on the height of your antenna, so attaching a longer portable antenna can increase the usable horizon point, somewhat. While it may not necessarily be a huge increase as the radio is still near eye level, the higher gain achieved with these antennas can significantly extend your reach to distant repeaters.
In preparation for this training topic I borrowed a few antennas from my neighbor KD5EXG and performed some tests of repeater and simplex communications. For those who are interested I will publish a separate blog post later this week containing information about the two antennas used in the test.
As a baseline, using the stock antenna that came with one of my handheld radios I attempted to reach the Sedgwick and Blue Springs Hill repeaters from an address in Logan. With the antenna about 6 feet from the ground I was transmitting from 4,537 feet elevation next to a 2-story building. I was not able to connect to either repeater using the stock antenna.
Next, I used an Abbree 42” tactical antenna at the same location. With this antenna I was able to reach the Sedgwick and Blue Springs Hill repeaters using the high-power setting of my radio, rated by the manufacturer around 5 watts. For reference, the Sedgwick repeater is at 9,145 feet elevation with a distance of 53.6 miles from the transmit location, and the Blue Springs Hill repeater is at 5,450 feet elevation and 29.1 miles from the transmit location.
Later that day, with the help of KE5HHW I tested the antenna in a simplex application where the transmit and receive locations were within a 6-mile radius, but with the higher elevation of Little Mountain in between. From his mobile radio with an attic installed antenna I was able to copy him very well, but at high power my signal opened the squelch on his radio but was not readable.
In a separate simplex test from a different location south of Newton, a station 10 miles away in Richmond received my signal using a multi element antenna on a tower and I was able to successfully communicate with this station. For this test there was also a terrain obstruction in between the transmit and receive location, but the increased gain of the 42” transmit antenna and the height of the receiving antenna were able to overcome the obstructions of the terrain and curvature of the earth.
On another day I completed a single repeater site communication test using a 16 inch whip type antenna also lent to me by KD5EXG. From the same location in Logan I was able to connect to the Sedgwick repeater with this smaller antenna with the same building obstruction in between.
While the simplex tests proved that overcoming terrain obstructions with longer antennas is extremely difficult with a handheld radio, I was especially encouraged by the results of the ability to connect with the two distant repeaters. At a price range of $12-$17 for the models used in the test, either antenna option would be an inexpensive and beneficial addition to a handheld radio.
A magnetic mount antenna mounted vertically and as high as possible on your vehicle is an inexpensive means to increase reach of a handheld radio in a mobile application.
Likewise, in a base station application, the reception capability and transmit range of a handheld radio increases significantly if you are able to incorporate an exterior antenna as high as possible. Routing a length of coax outside a structure to an inexpensive to buy or build j-pole antenna will increase the distance you can communicate via simplex, and improve your ability to connect to repeaters.
With many stations checking-in to this net via handheld radios, an attempt to improve the readability for all was to use the cross-band repeater function of a mobile radio. I believe the repeated signals of stations here in Newton can be heard farther away, but the problem of overcoming the elevation of Little Mountain has not been resolved for the stations residing in Cornish.
While it would be nice to have a dedicated repeater at higher elevation, resources are not available, and would somewhat diminish our purpose of testing emergency communication capabilities. With this in mind, if you hear a station attempting to check-in but I do not acknowledge, please jump in with a relay. I hope those who are not heard during roll-call because of the difficulty in simplex communication will continue to follow along with the blog, and notify me by text or email when you do join us.