Category: Featured Projects

This item is an ERI Model 788A-SP High-Efficiency FM Analog/HD Digital Diplexer. ERI’s innovative All Pass™ design allows stations to operate hybrid digital with HD Radio™ power levels up to -10dBc. The All Pass Diplexer maintains high efficiency while incurring a much smaller penalty to performance than other methods currently available. The analog insertion is less than 0.35 dB, and the digital HD Radio signal loss is less than 1.4 dB with digital group delay variation less than 600 nsec and is fully compliant with the HD Radio™ FM Transmission System Specifications. The 788 is an ideal choice for FM stations that have very high FM transmitter power output requirements due to long transmission line runs and also have the desire to operate at elevated HD power levels.

The antenna elements freshly painted and with its markings added to aid in assembly at site. This is an SHPX-8AC FM antenna bound for Dallas.

An ERI Model 100A-1M-DP Directional FM Antenna packed and awaiting pick up. This antenna is for a new FM translator which will rebroadcast WVLG AM 640, licensed to Wildwood, Florida.

The ERI Model CF103 Low Power FM Group Delay Equalizer provides group delay pre-correction for FM transmitters at low level, usually between the FM transmitter’s exciter and intermediate power amplifier.  The pre-correction applied offsets excess group delay variation and asymmetry that is unavoidable in FM combiner systems that include closely spaced frequencies, of 1.8 MHz or less.  The CF103 has a power rating of 150 watts and provides up to one microsecond of correction across a single FM broadcast channel.  ERI also has available group delay equalizers that operate at high power, which offer greater correction range and are located directly before each individual station’s combining module.

A 12-bay AL PLUS UHF television antenna in final test. This is a directional circularly polarized antenna is built for RF Channel 22 and has a wide cardioid directional azimuth pattern. All AL PLU antennas include 15-inch (381 mm) standoff brackets for mounting on poles or tower legs from 1.5-inches (35 mm) to 7.5-inches (191 mm) OD

The tower pictured is one of two (2) 360-foot base insulated AM towers that straddle West Gandy Boulevard, the Courtney-Campbell Causeway. This AM facility operates at 620 kHz and was originally owned by the City of St. Petersburg and operated with the Call Letters WSUN and in 1932 became the first directional AM facility. The directional nighttime pattern protects co-channel WTMJ, Milwaukee. These two towers were designed, fabricated and installed by ERI 2005. The base section of each tower is a four-sided structure that matches the base dimension of the original towers built in 1932. Each tower transition to a traditional triangular configuration for most of their height.

The tower pictured is the Milwaukee PBS 3-arm candelabra tower located in Milwaukee’s Estabrook Park neighborhood. At the tower top are Milwaukee PBS’s television stations WMVS and WMVT, WVTV, WIWN and a number of Low Power TV facilities. On the tower shaft below the candelabra is Milwaukee Radio Alliance’s B93.3, WLDB, which is the 2-bay ERI SPHX-2AE which is near the top of the photo. The antenna below that is iHeart’s WMIL-FM’s ERI SHPX-2AC auxiliary FM antenna, which is equipped with optional radomes, and is protected from falling ice by an ERI INVISI-SHIELD®, Electrically Transparent Ice Shield. WMIL-FM’s main antenna is also an SHPX-2AC with radomes and it is out of frame at a little over 100-feet above the WLDB antenna.

This is a UHF RF System for a Repacked Television Station. The system includes a 6-section UF5000 band pass filter, a 5 kW test load, a 3-port QUICK PATCH™ Coaxial Patch Panel and adjustable directional couplers at the filter input and output and at the test load input. The system is rated for 5.0 kW average power. The system is integrated into a floor mounted rack frame.

This is a four channel FM combiner which will feed a new multiplexed Model SHPX-6AC-HW-SP ROTOTILLER® FM antenna. The combiner is built from three (3) reflective 955 Series FM Band Pass Filters configured as a manifold combine and the fourth FM station is added to the system with a 955-6 Constant Impedance Combiner Module. After installation the antenna will be field tuned and the combiner assembled and tuned, including taking data and providing a written intermodulation products report, by ERI Field Service.

These AL PLUS™ UHF Television Antennas have completed tuning and final test and are bagged for shipment. Once they are crated they will be on their way to site for installation by an ERI crew.