Paul Thurst – Page 50 – Engineering Radio

Brother, could you help a pirate out?

It is not news that the FCC has its hands full with the FM pirates in the NYC area, particularly Brooklyn. On any given night, as many as thirty unlicensed signals can be heard, jammed between the commercial and non-commercial broadcasters in the FM band.

I am quite sure that other parts of the country have similar pirate problems. I do not see the FCC getting much more funding for enforcement purposes.

John Anderson asks; perhaps a pragmatic approach?

For most engineers, this will be a non-starter. Engineers (and other technical people) tend to see things in binary; on/off, right/wrong, black/white, legal/illegal, working/broken, etc. It is the nature of logic and dealing everyday operating status’ of technical equipment. A transmitter that is halfway working is broken. There is very little grey area in the interpretation of these things, nor is there very much human element. One cannot reason with a broken piece of equipment; it is to be either repaired or replaced.

Helping a person engaged in what is ostensibly an illegal activity, no matter how pragmatic such help might be, or how just or helpful the illegal activity may be to the community, would not be something that most radio engineers that I know would want to take part in.

Truth be told, some good might come from helping pirate broadcasters clean up their act. Over modulation, spurious emissions, and poor quality transmitters all create bigger problems for everyone else. The moral dilemma is what type of help to offer and can this or any technical advice then be used to make bigger and better pirates.

I don’t know, but it may be time to start thinking about things like this…

Winter! Is upon us….

What better time to take the gondola to K-1? None, none at all. We do work for the two radio stations that are on the peak of Mount Killington, near Rutland, Vermont. In the summer, usually, we can drive up there in a four-wheel drive truck. In the winter, the gondola is the way to go. On this day, there was a 48-56 inch base, light north winds, and air temperature around 10° F (-12° C) .

The reason for the trip today; is repair work on the Nautel VS2.5 transmitter. All three power supplies and the power supply summing board needed to be replaced.

MPX over IP

In the progression from Circuit Switched Data to Packet Switched Data, I can think of many different applications for something like this:

The FMC01 MPX to IP encoder can be used for multi-point distribution (multi-frequency or same-frequency network) of FM Composite audio, or as a backup solution over a LAN bridge, LAN extension, or public network. I can think of several advantages of using this for a backup when composite analog STLs are in use. There are many compelling reasons to extend the LAN to the transmitter site these days; Transmitter control and monitoring, security cameras, office phone system extensions, internet access, backup audio, etc. I would think, any type of critical infrastructure (e.g. STL) over a wireless IP LAN extension should be over a licensed system. In the United States, the 3.6 GHz WLAN (802.11y) requires coordination and licensing, however, the way the rules are set up, the licensing process is greatly simplified over FCC Part 74 or 101 applications.

Another similar CODEC is the Sigmacom Broadcast EtherMPX.

Features include:
• Transparent Analog or Digital MPX (MPX over AES), or two discrete L/R channels (analog or AES).
• Built-in MPX SFN support with PTP sync (up to 6.000km in the basic version). No GPS receivers!
• Unicast or Multicast operation to feed an unlimited number of FM transmitters with MPX from one encoder.
• Linear uncompressed PCM 24-bit audio.
• Very low audio latency: 2,5mS in MPX mode.
• Perfect match with Sigmacom DDS-30 Exciter with Digital MPX input.
• Can be used with high-quality 802.11a/n Ethernet links.
• DC coupled, balanced Analog inputs & outputs with -130dBc noise floor.
• No modulation overshoots due to compression or AC capacitor coupling.
• Decoder provides simultaneous Analog & Digital output for transmitter redundancy.
• Aux RS232 serial transparent link, Studio to Transmitter.
• Auto switchover to Analog input when Digital signal is lost.
• Centralized remote control & management software

One last thought; separating the CODEC from the radio seems to be a good idea. It allows for greater flexibility and redundancy. Using an MPX-type STL allows sensitive air chain processing equipment to be installed at the studio instead of the transmitter site.

Well, crap

Radio Shack Store, Courtesy of Wikipedia

Radio Shack (AKA, RadioShack, The Shack, Tandy Corporation, Realistic, Optimus, etc) appears to be filing for Bankruptcy if the Wall Street Journal and Reuters is to be believed. I see the words “private equity firm” in the article, that does not bode well.

Radio Shack of late has become a glorified cell phone store. It used to be one could get some emergency repair parts, an FM antenna, or a CB radio as the need arose. As a young lad, it was fun to poke around and look at the various radio kits and other assorted fun things. My first shortwave radio was a kit from Radio Shack; assembly finished just in time to hear the Vatican Radio’s announcement that Pope Paul IV had died.

What happened to Radio Shack is fairly typical; what was once a niche market for hobbyists and experimenters tried to go mainstream and lost their core customers. There are still plenty of electronics hobbyists out there, look at the Amateur Radio community as an example. Yet, that market was abandoned for the more lucrative general consumer electronics market. Unfortunately, Radio Shack never produced high-quality stuff, so their reputation in the consumer electronics market was not that great. Thus, not being known for anything, they slowly slipped into irrelevance.