engineers

Engineer's Corner
4:50 pm
Thu November 21, 2013

TheEC: 1290AM Heard in Norway

Longwire antenna used to successfully receive 1290AM in southwestern Norway.
Credit Arild Skalmeraas

We've talked in the past about skywave propagation, but it's cool when you heard about real-world examples of it.   Recently I've gotten several emails from "DX'ers" (Distant Reception enthusiasts) in Europe saying they've been able to hear Latino Public Radio on 1290AM all the way across the Atlantic!   

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Engineer's Corner
1:43 pm
Tue November 12, 2013

TheEC: 91.5 is Back On the Air

From top to bottom, Bext LEX30 transmitter, Dayton 210 FM receiver tuned to 102.7 to get programming to feed the transmitter, and Inovonics 631 FM receiver to monitor 91.5 on the speakers above.
Credit Aaron Read

As of Tuesday November 12th, WCVY is back on the air in limited fashion.   As you know, WCVY suffered catastrophic damage to its equipment and facility from a roof leak during a thunderstorm in August.   The entire space had to be gutted to the concrete walls, and new electrical wiring and drywall installed.  Much of the transmitter gear either took direct water damage (e.g. electricity shorting out) or took indirect water damage (e.g. rust and other corrosion), and eventually a lot of it failed completely.

We have put a temporary setup in place with a donated 30 watt transmitter on loan (with the antenna array's gain factor of 2.1, it's really more like 63 watts of Effective Radiated Power), and a special radio that's tuned to 102.7FM (there's a high-gain FM antenna on the rooftop tower) and puts out the composite signal directly into the new transmitter.   This effectively makes 91.5 into a "repeater" of 102.7FM.

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Engineer's Corner
12:39 pm
Thu October 17, 2013

ARRRR - Pirate Broadcast on 102.9FM

Close up of a whip Antenna, believed to be the source of the 102.9 pirate.

UPDATE 01/21: Multiple letters sent with no response, and the pirate's still broadcasting.  A letter has been mailed to the FCC's Enforcement Bureau.   If you are an RIPR listener to 102.7 and you have experienced interference due to this pirate, you can submit your own letter to the FCC as well.

UPDATE 12/19: The pirate has been found!  Well, we're pretty sure we have found the pirate.  Using a directional antenna and a signal meter, we triangulated the position to a house a few blocks from the Locust Grove Cemetery in South Providence.  

A letter of notification of interference to RIPR was mailed to this address several weeks ago, but apparently this pirate doesn't care as there's still an illegal broadcast on 102.9 from this location.

UPDATE 11/5: Thanks to a fellow engineer who informed me there is a pirate broadcasting on 102.9FM and that is likely the source of the interference people have reported (see below).  Quite possibly the atmospheric changes made it worse, but the bulk of the problem is likely the pirate.

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Engineer's Corner
3:00 am
Tue October 15, 2013

TheEC: More Fiber in RIPR's Diet

Fiberoptic cable splicing tool.
Credit Aaron Read

As all RIPR fans know, we are an NPR member station.  That means we get a lot of our programming from NPR, the BBC, and other providers, via our satellite dish.   The dish is medium-sized as dishes go, but it’s pretty big in real terms: 3.7 meters (12ft) in diameter.   There’s quite literally nowhere to fit a dish that large at our studios in 1 Union Station, so instead it was installed out at our 1290AM transmitter site in North Providence (we still own 1290, but we lease it to Latino Public R

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