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Are Your TFT EAS Units in Compliance?

Also: Why it’s a good idea to check your RF sites regularly — and bring binoculars

There have been a number of questions about whether TFT EAS units comply with current regulations. As you recall, TFT recently closed its doors; but former employee Darryl Parker has tried to help former clients when he can.

Darryl writes that all TFT EAS products supported recognition of the FIPS code “000000” from the very first unit.

Way back in 1994, its design engineers recognized that, although the company had portion codes that could be extended to all of a state FIPS code, as well as a county/parish FIPS code, there was no designation for “All United States.”

With FCC permission, he said, TFT integrated that FIPS code (000000) into the first EAS Model 911. Type-Acceptance requirements at the time called for all the Event Codes, including NPT, to be included. Those, of course, were in the first EAS Model 911 delivered more than 20 years ago. Thus, no changes or upgrades are necessary to any TFT unit for current compliance.

While at TFT, Darryl prepared a document that outlines the steps necessary for auto-forwarding of NPT Event Code messages with an accompanying FIPS code of 000000. All TFT units can manually forward any EAS protocol message received. For a copy of this PDF document, send a request to [email protected].


Fig. 1: A good reason to view your FM antenna periodically with a pair of binoculars. The unexpected tenant is visible above the Shively bay. Here’s yet another reason to visit your transmitter sites periodically — and to bring a pair of binoculars with you.

Steven Donnell discovered a new “tenant” that had appeared suddenly just above one of his Shively FM antennas, visible in Fig. 1. Steve had noticed a slight increase in standing wave ratio, an indication of power mismatch. The SWR indication was not enough to warrant immediate alarm. Still, a closer inspection found this new occupant.

Turns out it’s some type of IP radio antenna. Steve has identified the owner; the antenna will be relocated soon.

He also told the owner that he would be happy to reduce transmitter power while the tech is working on the tower so he won’t fry his brain too badly, like he did the first time.


Albuquerque, N.M., broadcast engineer Bob Henry did a stellar job identifying the equipment shown in Burt Bowman’s remote studio from the Wooster Fair in Ohio.

Bob identifies the microphone as a Shure SM58. The “stick” type of dynamic microphones didn’t appear on the scene until the early ’60s. The SM58 was manufactured in 1966, and it had the steel mesh ball-type windscreen like the one in the photo.

The black box sitting next to the microphone stand is an Audiolab Electronics TD-1A bulk tape eraser, needed for wiping reel to reel or tape cartridges clean before recording. It was introduced in 1959 with the founding of Audiolab Electronics. This was the first commercially available AC tape degausser. A later model, the TD-1B, had a black top surface.

Fig. 2: Were you able to identify the gear? Fig. 2A: A workhorse RCA Type 70-D turntable.
The turntable is an RCA Type 70-D series, seen in Fig. 2A.

Bob writes that the RCA 76-C console was made in the early 1950s. He calls attention to the wear marks on the console, near the pots and switches (near Burt’s left hand). This would indicate that the board had been well used over the course of time. That particular model was built in 1951, and it was not uncommon for stations to hang on to their older broadcast equipment for 20 years or longer.

The older gear was definitely made to last.


Fig. 3: A square conduit at left channels Cat-6 cable into the plenum ceiling. The days of sloppy data cable layouts are over!

Broadcast engineer Matt Aaron offers the tip in Fig. 3 as a neat method of getting a run of Cat-6 cables from the cable tray into the ceiling. Note the conduit at left. One of Matt’s contract clients had a cabling company run the Cat-6.


Ben Dawson, P.E., principal engineer at the firm Hatfield and Dawson, makes us aware of a useful radial-finding resource. It’s a three-image PDF that you can download at

The desensitization technique described is important if you are looking for radials and station power is more than a few hundred watts. The field meter loop has to be lined up with the direction of the radial, and will pick up from the antenna as well and often be out of the range of the meter unless it’s de-sensed.

Fig. 4: Hatfield-Dawson grip provides convenient carrying hardware. The Hatfield-Dawson grip (Fig. 4) is made from cupboard door handle hardware. The thread in the FIM is 1/4-20 to fit a standard camera tripod.

The websites of professional consulting companies like H&D are excellent resources for useful engineering information. Spend some time checking them out.

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Author John Bisset has spent 46 years in the broadcasting industry and is still learning. He handles West Coast sales for the Telos Alliance. He is SBE certified and is a past recipient of the SBE’s Educator of the Year Award.