Tom's Tech Talk (#11): Antenna Systems

 I can’t tell you how many times we run across systems improperly designed based on their licensing requirements. Each FCC licensee is required to meet both height and power requirements for all of their fixed base station equipment that is indicated on their license.

      Many times people take the approach that to reach their people in the field they need to increase the gain of their antenna’s and the power on their base stations. What they don’t realize is that they may become an interferer with an adjacent co-channel user and  are therefore  subjected to a fine by the FCC for exceeding their licensed effective radiated power. We had one instance where the combined antenna gain and power from their equipment was enough to reach Madison Wisconsin from the Western Suburbs of Chicago.

      In schools, a strong communication system is vital to maintaining a safe environment. Whether reassuring seamless alarm alerts or connecting with the needs of students, instant communications are essential. The community in a school or university includes personnel - grounds and maintenance, administration, faculty and students. Here are some examples of situations where two way radios can come in more than handy.

Scenario #1:

Campus security at a University receives a call in the middle of the night that someone in a mask is lurking around one of the academic buildings. They send out a broadcast with their two way radios, and the nearest guard checks out the area.

Result: Because there's a quick response, the intruder is scared away before causing any damage.

Leon Tompkins

     Leon started for Chicago Communications in 1968--giving him a whopping 43 years of experience! Though his time here has been the majority of his career, if it weren't for a couple minor gigs, he may have never made it to ChiComm in the first place. So how is it that he did stumble upon the company? Let's start from the beginning.

Tom's Tech Talk (#10): Digital Mobile Radio System Implementation

      In today’s Digital Mobile Radio systems, networking is playing a key role in implementation of these radio systems. Years past connectivity was through an in house set of wires or over the local telephone companies telephone line. With the evolution of radio, not only has product changed, but the way we need to get the information between sites has changed.

      In the early years, radio equipment was controlled by Direct Current (DC) traveling down the telephone lines between dispatch and the radio at a tower. The voice and DC current would travel the line to the equipment. The equipment in turn would interpret the DC current as one of the following:

 1)      Transmit on F1

 2)      Transmit on F2

 3)      Monitor the Channel

Fred Budge

Fred has 38 years of experience being a Bench & Field Technician. He started at Chicago Communications in 1991. He specializes in portable and mobile two way radio component work, which is rare today. A lot of other shops don't go past a certain point of repair into the detailed component issues, but Fred still does.

 

Career History: After graduating from high school in 1967, Fred attended a college with a 2 year Technician/Electronics/Engineering program where he determined his interest was in communications. Just after finishing, he was drafted into the army for the Vietnam war for 2 years. Afterwards, he started working for MetroCom, which was a chief competitor with Chicago Communications for many years.  He worked as a Bench/Field technician there for about 17-18 years until they were bought out by ChiComm. He decided to stay on with ChiComm doing the same type of technician work. He continued his education by taking courses and teaching himself on the job in addition to the 2 weeks a year that ChiComm sends him to training sessions.

Our Customer Service Expert

Linda has worked at ChiComm for over 25 years. Dave O'Brien hired her in 1986 when Jerry Bear owned the company. She started as a member of the reception and customer service personnel in the Elk Grove shop but as time passed she took on many other responsibilities and roles within the company including collections, billing & payroll in addition to many other miscellaneous tasks that a customer service position can bring. She wore multiple hats as one might say. She's stayed at Chicago Communications because of the flexibility she's given to do her job and the long lasting friendships she's made over the years with co-workers.

"Share the Vision"

This video was made by Motorola Solutions, our premier partner in service, for a piece in the Motorola Road Show earlier this week. Chicago Communications was able to lend advice on the process of guiding customers to a system migration plan and how to implement this plan. As our Sales Director Tom Treichler says, "A lot of customers don't know they have the capability to go to the next level and it's up to us to educate them and tell the story of where they can go and show them the benefits of what they can do."

Tom's Tech Talk (#8): "Sync" Your two-way Radios & Accessories

     As most people believe that hooking up a radio is a couple of wires, consider this. Typical radio antenna connections are 50 ohms of impedance. Antenna cable comes in many varieties. For instance your Cable TV Cable is 75 ohms impedance. Twin lead for an outdoor antenna is 300 ohms. Standard 2 Way Radio cable is 50 ohms. In layman’s terms, ohms equates to the resistance of a part or device. When mixing different varieties of cables, you actually get a mismatch. This mismatch usually results in degraded performance or even failure.

    For two way radio, the typical impedance is 50 ohms. This means that the radio should match the antenna cable and the antenna cable should match the antenna. When done properly you obtain maximum transfer of power to the antenna. When done improperly the mismatch can actually cause reflected power back into the radio either shortening the life of the amplifier or causing degraded performance in the operation of the radio.

Tom's Tech Talk (#7): Ready for the Next Emergency?!

With the recent weather-related incidents happening around the US and the world for that matter, now is a good time to assess your backup plan for communications. When developing a backup communications plan, you have to consider what type of an emergency you are planning for. It's usually:

1) Your radio system is impaired and you need an alternate method of
communications.
2) You have to evacuate your facility leaving the equipment intact and
operational.
3) You have an incident which has completely taken out your building,
equipment or tower and you have to relocate.

How long will a radio last during the day?

Battery capacity and the duty cycle of the radio will determine talk time. Typically a radio AT MINIMUM should last 8 hours. Over the years as batteries age, their ability to meet the customers requirements diminish and the batteries need charging during the shift or workday. New technology such as Motorola’s Impress battery systems enhances battery life as the charging systems are intelligent and adjust the charge rate for the type of use. Battery technology changes over the years have led to increased battery life as well.

What is digital?

Digital is a process to modulate the radio channel or frequency using data instead of traditional analog voice. By converting ones voice into a data stream and sending it over a radio channel we can improve the ability of the signal to be decoded and reproduce the audio at the other end to be heard. All cellular systems today use digital technology. Two way radios have both analog and digital. Digital affords some additional benefits such as a two for one channel usage. Thus one frequency or channel will allow you two simultaneous transmissions. This may allow for reduced costs in radio equipment.