The new KHLX antenna is atop this tower.
SACRAMENTO, Calif. I was up against a tight deadline. It was 4:55 Friday afternoon and KHLX(FM), Clear Channel Communications’ new station going into the Sacramento market, was scheduled to go on air two days later on Sunday. But I needed some last-minute transmission line elbows and couplings to make it happen.
I called Greg Montano, my sales-engineering contact at Jampro Antennas, also located in Sacramento, and he arranged for me to pick up the missing links I needed after closing hours that night. It’s certainly helpful having your antenna maker virtually in your backyard, but that’s not the only reason with went with a new six-bay Jampro JHPC-RFR configuration for reduced low-angle radiation near KHLX’s tower. We were doing a classic two-step move to get into the Sacramento DMA.
We moved KHLX from Susanville to Pollock Pines and did a station upgrade in order to serve the market with classic hits and news at 93.1 FM. Our company purchased the Pollack Pines license for KJDX(FM), which we downgraded from Class C to a Class A station, and then upgraded that station by moving to Somerset, Calif., as a B1 at 20.5 kW ERP.
Issues
We had a great tower location that we would share with KCCL(FM), a Class A station owned by Results Radio Group.
KCCL was already using a Jampro antenna and we were impressed with their coverage. Since they were familiar with the site and conditions, we decided to have Jampro build us a duplicate antenna that could handle the higher power level; that turned out to be Jampro’s JHPC, a high-power version of their Penetrator series rated 50 kW maximum input.
I called on Doug Tharp at SCMS for the transmission line as he had 2-1/4-inch available. For our TPO, calculated at 12.5 kW, 1-5/8 would be marginal and 3-1/8 would be overkill, but 2-1/4-inch is less used and more difficult to locate. Luckily, Doug had 300 feet at hand.
I really didn’t shop the antenna in terms of price, but the cost looked reasonable. It was really our GM and director of engineering who wanted to go with Jampro because of past experiences.
Jampro performed pattern optimization tests and provided us with 10 plots to select from and we chose the one that we thought would provide optimal coverage of the desired area taking into account terrain considerations.
The antenna was delivered on time, without incident and the installation without issue, that is, until I realized we needed a few last-minute transmission line fittings. On Saturday we made the last few connections.
When I first fired the new transmitter into the line I was not sure what I was seeing. With 12.5 kW of transmitter power output there was less than 5 W of reflected power. I actually installed a through-line wattmeter just to verify what the transmitter, a new Nautel NV20, was reporting, and it agreed. There’s no such thing as a perfect antenna, but the lower that number the better the match and it appeared to be a good one. Further, the coverage is impressive. The feedback on the signal that I have received from our management and our listeners has all been positive.
I am impressed with the antenna’s performance. It went right up and we had no problems. It wasn’t a last-minute project, but because of the permitting and the electric utility delays it came down to the wire. So it was nice that Greg Montano was able to help us out and that when we finally fired it up we didn’t have any surprises.
Gregg Garcia is chief engineer for KHLX(FM).
For information, contact Jampro Antennas in California at (916) 383-1177 or visitwww.jampro.com.
