A rough guide to the range of the proposed CJLO FM transmitter. Red areas would experience interference from WVPS in Vermont.
After much study, Concordia student radio station CJLO 1690 AM believes it has found a solution to reception problems it is experiencing at the university’s downtown campus. A long-rumoured application for a low-power FM retransmitter was published Friday by the CRTC.
If approved, the transmitter would operate on 107.9 FM, from an antenna on the Henry F. Hall Building, at 100 watts.
The frequency is one that has been previously identified as potentially usable in Montreal, but it comes with one big downside: It’s the same frequency as WVPS, the Vermont Public Radio transmitter in Burlington, and the only U.S. public radio station that reaches into Montreal.
Because of co-channel interference from the 48kW VPR transmitter, the CJLO FM retransmitter would have a very limited range, basically covering the core of downtown and not much else. On the other hand, areas around downtown will experience a great deal of interference, likely hearing both stations at the same time, and neither very well. (I can’t get too specific about this because the maps submitted with the application are blurry and black-and-white because they were sent by fax).
Though VPR’s 107.9FM signal reaches Montreal remarkably well, it is not protected in this city. We learned this two years ago when a proposed station in Hudson offered 107.9 FM as an alternate frequency if its first choice of 106.7 was rejected. The CRTC received some comments from VPR listeners upset at the potential of no longer being able to hear that station.
CJLO’s AM antenna on Norman St. Increasing its power, or putting a transmitter like this downtown, are impractical solutions to downtown reception problems.
CJLO’s report, prepared by broadcasting consultant Michel Mathieu, notes that signal strength readings were taken along Sherbrooke St. and de Maisonneuve Blvd. downtown, and they showed that the signal is particularly bad in the heart of downtown where Concordia’s downtown campus is. The signal starts dropping around Atwater St., and returns around Berri. The reason? Downtown skyscrapers absorbing the AM signal.
Even Laval, more than twice the distance away, shows a signal 10 times better than in some downtown blocks.
In case the quantitative data isn’t enough, the application also includes a dozen letters from CJLO listeners complaining of the signal quality downtown.
There’s clearly a problem here, and a low-power FM retransmitter makes the most sense as a way to solve it, even though the choice of frequency might not be to everyone’s liking. (Mathieu notes that even VPR’s signal is hard to receive downtown because of the same interference problems that CJLO experiences.)
CJLO’s application noted that it studied other options:
- Increasing the power of its 1,000W transmitter in Lachine’s St-Pierre district was rejected because it wouldn’t solve the problem. Even TSN 690, operating with giant towers at 50,000 watts on a clear channel, has signal reception problems in downtown buildings.
- An AM repeater (it’s unclear if this would have been on the same frequency or another one) “became out of the question” because of practical and cost limitations, being unable to put a 75-foot antenna on top of the Hall Building.
The report doesn’t mention looking at other FM frequencies, but with the FM band effectively at capacity in the city, it would be difficult to locate one to put even a low-power transmitter without causing interference
CJLO’s application can be downloaded here (2.8MB .zip file). The CRTC is accepting comments on CJLO’s application until 8pm on May 26. They can be submitted using this form. Note that all information submitted, including contact information, becomes part of the public record.
UPDATE (May 4): CKUT’s International Radio Report devoted its show on Sunday to this application, with comments from supporters of CJLO and VPR. You can listen to the show here in MP3 format.
Meanwhile, VPR is warning its listeners about the CRTC application and its consequences.