FM – Page 3 – Engineering Radio

Radio is dead? Don’t tell these guys then…

WXHC in Homer, New York will never be listed on the NY Stock Exchange. Is that bad?

They don’t think so. A small class A FM station, one of many that signed on in the early 1990’s as part of the 80-90 drop ins (FCC docket 80-90, for those unfamiliar). Many of these stations did not fair too well and ended up being absorbed by larger stations and groups starting with the first wave of ownership deregulation in 1993.

WHXC has remained under the same ownership since it signed on in 1991. Eves Broadcasting is a family operation, employing maybe half a dozen people. Their studios and offices are on the third floor of the Bank of Niagara right in the center of town. The facility is very nice. Like any successful radio station, their focus is the community they serve. The format is “Oldies” but they also broadcast high school football, Syracuse sports and so on. They host a yearly Blue Grass festival on the village green.

The air studio has an Arrakis console and uses BSI Simian automation software. They have live DJ’s from 6am to 6pm, local news, weather, sports, etc.

The production room has a BE Spotmaster 8S200A console from 1978. Aside from needing some power supply capacitors, it still works relatively well. However, as the owner’s son said; that thing belongs in a museum.

BE Spotmaster line input card. Probably can still get all these parts if we wanted to.

I forgot to take pictures of the transmitter site when I was there. Next time.

We will be working on several projects for these folks, so I will keep you posted on the progress.

Pittsfield Massachusetts’ newest “Metro-Station” 103.3, W277CJ

We have been poking away at this one for the last year or so. It seems that the previous owners of Berkshire Broadcasting had filed for a translator to rebroadcast WNMB, (100.1 WUPE-FM) North Adams in downtown Pittsfield, during the great translator rush of 2003. When the CP showed up in the mail last March, the current owners were quite surprised.

After looking at the Construction Permit, we made some modifications;

Moved the transmitter location from 100 North Street to 1 West Street (Crowne Plaza Hotel) which is the tallest building in Pittsfield. Antenna AGL is 44 meters (145 feet).
Changed the rebroadcasting station from WUPE-FM, North Adams to WUPE-AM Pittsfield
Changed the antenna to non-directional
Changed the ERP from 48 watts to 100 watts

We were able to make those antenna and power changes because we changed the parent station to the local AM station, WUPE, 1,110 KHz. The previous power/pattern was submitted to keep the translator signal within the 60 dBu contour of the FM station in North Adams.

This, I feel, is the best use for an AM to FM translator. WUPE-AM is a class D station with no night time service. Adding a night time service greatly increases the station’s value to the community. While the 100 Watt translator does not cover near as much as the 5,000 watt AM station, the transmitter location is right in the center of Pittsfield, so coverage of the population center is excellent.

The view from the top of the Crowne Plaza is quite spectacular. I am pretty sure I will have a lot of transmitter maintenance to do right about the middle of October.

The installation is fairly straight forward:

W277CJ installation, roof of Crowne Plaza, Pittsfield, MA

The outdoor enclosure is a DDB POD-16DXC which is rather nice, it comes with rack rails and a thermostatic controlled fan.

The antenna is a Shively 6812B with RADOMES. The transmitter is a BW Broadcast TX600v2. I really like these transmitters, they are well designed and rugged. We have yet to have a single failure of one of these units in the field.

The station ERP is 100 watts, so a small bit of calculating is required to arrive at the proper station TPO. I find it easier to make all these calculations in the decibels per milliwatt (dBm) unit domain, then convert back to watts. Thus, the ERP is 100 watts, or 50 dBm. The antenna has a gain of -3.4 dBm. We used 25 feet of LMR-400, which at 103.3 MHz, has a loss of -0.26 dBm. The total losses are -3.66 dBm, making the necessary TPO 53.66 dBm, 232.27 watts or rounding down to 232 watts.

Upgrading the firmware

The original V series Nautel transmitters have required a couple of firmware upgrades in some cases.

Upgrading the power module firmware, WDVT, Rutland, VT — Upgrading the PA module firmware on Nautel V-5D transmitter, WDVT, Rutland, VT

The first was for the controller to add a little bit of bias to the PAs during analog operation. The second one I have had to do is to the PA modules themselves which was to keep the power supplies from shutting off during re-transfer from Generator power to commercial power.

I have done several of these and once you get the hang of it, it only takes a few minutes to complete. Still, I remember when transmitters didn’t have firmware. The low voltage control circuits were either 120 or 240 VAC with big relays and contactors that loudly confirmed their closure before any meters began to move.

Regarding Nautel transmitters in general; the newer models are not same rugged, reliable designs that were common in the past. We have AM ND series transmitters that have been on the air for 20 years without a single failure. The models rolling out of the factory these days often have switching power supplies fail without reason or warning and RF pallets that are fragile things. Ah well, I suppose all things are cyclical.

The General Electric BY-4-C FM broadcast antenna

Whilst working in the generator room at WFLY, I found this bit of treasure stashed on an overhead shelf:

General Electric BY-4-C FM broadcast antenna, ca 1948 — General Electric BY-4-C FM circular broadcast antenna, ca 1948

That is a very old FM broadcast antenna from 1947-48. It must have been intended as a spare antenna in case the main antenna had a problem. It was never needed, so it remains in its original shipping crate. I would think that these were rather well made, since the original main antenna was in service from 1948 until 1970 or so, when it was replaced with a Shively 6710.

The entire antenna is intact including the interbay lines, power divider T’s and tuning section. Of course, it is of little use to the radio station today, as it is horizontally polarized. Perhaps some museum somewhere? I don’t know, it would be kind of neat to put it all together and use it as an exhibit.