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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.

W277CJ 60 dBu contour

W277CJ 60 dBu contour

The installation is fairly straight forward:

W277CJ installation, roof of Crowne Plaza, Pittsfield, MA

W277CJ installation, roof of Crowne Plaza, Pittsfield, MA

W277CJ transmitter in outdoor enclosure

W277CJ transmitter in outdoor enclosure

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

W277CJ Shively 6812B antenna

W277CJ Shively 6812B antenna

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.

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

  • StvCmty

    If the FCC opened a window for an AM with a commonly owned FM translator to turn in their AM license and turn the FM translator into a FM station able to original its own content would anyone take the deal? There would need to be some restrictions to keep the city of license of the original AM somewhat covered, considerations given to secondary status of the translator, and other hurdles to keep the system from being abused.

  • I’m a rank amateur, but used a TPO calculator online. For my LPFM, we used the same transmission line so I had that figure. This calculator doesn’t factor in the channel/frequency…

    http://allenk.home.infionline.net/fmtpo.html

    Online FM Transmitter Power Output Calculator
    V1.0 By Allen D. Kass © 1999
    =============================================
    Station Call Letters: W277CJ
    Comment: Pittsfield
    Transmitter Power Output Chart for 100 watts ERP operation
    +5% to -10% in 1% steps
    E-R-P T-P-O Per Antenna
    Total Total cent Input Power
    ===== ======= ==== =======
    105 245.6 +5% 228.26 Maximum Values
    104 243.2 +4% 226.09
    103 240.9 +3% 223.91
    102 238.6 +2% 221.74
    101 236.2 +1% 219.57
    100 233.9 0% 217.39 Nominal Values
    99 231.5 -1% 215.22
    98 229.2 -2% 213.04
    97 226.9 -3% 210.87
    96 224.5 -4% 208.7
    95 222.2 -5% 206.52
    94 219.8 -6% 204.35
    93 217.5 -7% 202.17
    92 215.2 -8% 200
    91 212.8 -9% 197.83
    90 210.5 -10% 195.65 Minimum Values

    Transmission Line: LMR # 400 Length: 25 Feet
    Atten/100 Ft=1.27dB Antenna Gain=0.46 Additional Loss=
    Transmission Line Loss at 100 Watts ERP=16.5 watts
    Transmission Line Efficiency at 25 Feet=92.95%

    Calculated 7/1/115 at 11:58:34 AM

  • I would trust your numbers better, Paul 🙂

  • In the fall, you may have to take a semi-nearby tower photographer up as well to update his site.

  • Gary

    Minor quibble: Gains and losses are in “dB”, not “dBm”. So if your antenna has a gain of “-3.66 dB”, you can apply that to either dBm or dBW. Regardless of that, all of your calculations are spot on.

  • Paul Thurst

    Gary, you are, as always, correct. Mike, I’ll give you a call about a fall swing through Berkshire County, or any place else you are interested in.

  • Nick Straka

    What are you using to feed it?

  • Paul Thurst

    Off the air feed is not possible, since the AM signs off at night. We have an internet connection with a couple of barix boxes

  • Paul, I listened to this today for the first time. Sounds really good! Nice and clean!

    Nice job!

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