This story has its beginning like many engineering service calls: An urgent plea of “Help, I''m off the air!” As I was on my way to a routine site inspection, I quickly decided to turn around and see what I could do to help a new client in need. Upon arrival I found the most immediate problem was a failed exciter. I was able to temporarily put the station back on the air with a substitute exciter. However, it quickly became apparent that the station''s older 2.5K transmitter had seen its better days. Many things had been neglected over the years and some parts were being held together with homemade repairs and a prayer. After talking with KBLP''s owner, I highly recommended a new transmitter for the site, as the cost to bring this old transmitter back to its better days would be very steep.
I began my search for an economical and efficient replacement that would meet my client''s requirements. Very soon I found one transmitter that stood out among all the others in the power class: an Elenos. The Elenos ETG 2000.20 had all the right specifications to replace its predecessor, but it also had an elegance of design, efficiency, and all in an incredibly small and lightweight footprint. At first, my past experience told me it shouldn''t be possible to fit so much in such a small box. I decided to contact Elenos, and I was assured the ETG 2000.20 could do everything advertised. The company even offered to ship me a demo unit to prove it to my satisfaction.
| ||Performance at a glance || |
| ||■ 2RU up to 2kW, 4RU for 3.5 and 5kW|
■ ICE-FET for cooler operation
■ Planar technology design
■ Redundant power supplies
■ 74 percent overall electrical efficiency
Within a few days a demo ETG 2000.20 transmitter arrived. I lifted the new transmitter from its shipping box eager to put it to the test. I connected the transmitter to ac power and a test load and was transmitting at 500W in just a few minutes. I was amazed at how easy it was to adjust the frequency and power levels from the front-panel menu I called my client and made arrangements for a real-life on-air test.
The next morning I loaded the lightweight new contender into my truck and drove to the KBLP tower site. Once onsite I disconnected the old transmitter, deciding to set the new Elenos in the STL equipment rack. For convenience and safety I elected to connect the transmitter with a short 240Vac power cord to provide easy removal of power during any future service work. The RF connection was made via a 7/16 DIN jumper that adapted to the station''s existing 1-5/8” transmission line. Next, I turned the transmitter on for the first time in its new environment. After a quick power-up sequence, the menu displayed current power, status and audio modulation levels. Different main and sub menu parameters could be accessed and manipulated through the large, rotary push-button knob on the front panel.
Within the submenus multiple station profiles each with separate frequency and power level settings can be stored. Obviously the different presets would be very useful in emergency transmitter service for multiple site operations. Modulation levels were displayed clearly onscreen in kilohertz deviation and with a quick reference bargraph. I established a main profile for the station with its frequency and required TPO.
Next I connected a small interface called an E.Box, this provided Web GUI access for most of the transmitter''s functions. In this instance the E.Box actually negated the need for a separate remote control. However, via a rear-panel DB25 connector, standard analog remote control connections are provided for traditional remote control systems.
Within 15 minutes I had made all the necessary connections. As the customer watched, I pressed the on button and the new transmitter whirred to life with a magical glow of its screen as it steadily increased power to 2kW forward power. There it was before me -- almost unbelievably -- this small technological marvel had replaced its 700lb power hungry predecessor.
After a few days the customer called with glowing reports of better sound and coverage than the station had in years. Needless to say, the customer wanted to keep the new transmitter and we finalized the sale and installation. It was decided that the old transmitter was to be permanently retired, with the new Elenos transmitter taking its rightful position as the new heart of KBLP, ready to serve the people of southern Oklahoma with pride for many years to come.
Tutor is owner of Tutor Consulting, Oklahoma City, OK.