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This is why one must stick with certified, legal transmitters:
https://docs.fcc.gov/public/attachments/DOC-357562A1.pdf
Their transmitter came from here:
TIB
Ya, I’m familiar with the one mentioned in the NOUO, Orion 5000, a rebranded Chinese one at 500 mW I think. It’s not shown in their site now.
I wonder where the church was located…right beside the airport? Must have been a very strong spurious signal to get to the control tower. If only people had a radio with the aviation/public service band to check these things.
The manual for the Orion-5000 transmitter says it’s FIVE WATTS output with a range of 1-5 miles. Not currently available on their site, but the manual is online:
https://www.manualslib.com/manual/620688/Mobileblackbox-Orion-5000.html?page=2#manual
Every transmitter on their website is illegal to sell in the USA.
My questions are: Why wasn’t there also a separate NOUO for broadcasting without a license on the FM broadcast band, and two, why isn’t there any followup of the FCC shutting down the sellers of illegal transmitters. The FCC knows who and where they are, heck they cited their website in the notice. It doesn’t take a genius to find their physical location and go bust them. There seems to be zero enforcement against blatant sellers of transmitters that are illegal to sell.
TIB
I stand corrected on the power of the Orion 5000.
I have always wondered about how all these Chinese transmitters are sold myself, not just in the USA but Canada too, not just from China but locally(USA/Canada) also via Amazon for one of a few sellers. And I know of a store just east of Toronto, Durham Radio, that were selling Ccrane stuff, radios etc, and got into trouble with Industry Canada for selling the Ccrane transmitter as it is not certified here but Amazon Canada continues to sell these 500-15 watt ones with next day delivery with Prime.
Yeah, they(FCC/Industry Canada) know about it….your guess is as good as mine as to why they can sell them as wouldn’t you go after the source, not the user who thinks they are for sale here so it’s OK?
Yeah my Chinese transmitter came in on Several Frequencies but again I was looking for Audio on the Radio or scanner. SOMETIMES IT SHOWS AS DEAD CARRIER OR HASH and the squelch would cause your scanner to scan past it and you think your dirty transmitter is clean when your spewing trash everywhere.
IM DONE WITH FM because of this and its AM for me. I will encourage listeners to buy the Terk AM advantage this way I don’t cause harm and because the loop is doing its job the listener hears me 2.5 miles away problem solved.
When lead paint is found on children’s toys or emission cheating by a car manufacturer is found it seems the government action is swift and sure, so why not in cases such as this. Enforcement needs to include the manufacturers and distributors in a greater extend, and to a lesser extent to end users.
Few end users have the knowledge or equipment to assure technical compliance with the rules so the most effective prevention method would be to enforce certification in the market for such equipment.
Sites such as ours have and should continue to educate regarding the possibilities of problems for those contemplating license free FM. It is definitely not “plug and play” but can be used if the transmitter is certified and operated according to instructions without range extending adjustments or modifications.
I still believe the best guide for those using FM is to make sure your range is 200 feet or less and there should be no problem, unless you are on the tarmac and emitting spurs.
Neil
The station in question is, according to Google maps, about 3 miles from San Antonio International Airport and about 5-6 miles away from Randolph Air Force Base. I’m certain there is a constant flow of aircraft overhead and within easy reach of a 5 watt transmitter pumping out spurs. Ground to air in this case would be a nice example of straight line of sight, non obstructed signal path.
This also makes a perfect example of why these illegal, uncertified FM transmitters are a public safety issue. You do not need to be next to an airport to cause trouble. A plane passing overhead that may be miles from an airport can have it’s communications interfered with quite easily by one of these transmitters.
TIB
Ouch and to think mobile black box was a very popular transmitter. I’ve heard them talked about on many different boards whereas people use them and like you said they did get out a good 4 to 5 miles at times. This is with the stupid little antenna that came with it now imagine what would happen if someone hooked up an outside antenna now you’re talking some serious interference.
What amazes me is that it took this long for the FCC to start posting the names of the transmitters that are causing interference to aircraft along with the fact that it does. If they had done that in the very beginning I think things might have looked a little different for Public Safety and everyone that was using them. I don’t believe that people would be boasting about them anymore after that fact.
Maybe this is a step in the right direction. Anyways it’s good that the word is getting out.
And also planes aren’t as high up and far away as one might think. Altitude is measured with sea level as a reference. So if a plane is flying at say 5000 ft that’s not 5000ft above the ground you are standing on….that’s 5000 ft above sea level so the plane is a lot closer than you think. A transmitter getting range of a couple of miles and putting spurs in the aviation band, will surely interfere with the plane’s communication as it flies over your location. Your signal goes up as well as out horizontally.
The legacy has a good point…I would like to see the makes of the transmitters published with the NOUO’s along what the interference was and the measured field strength.As a private pilot of 40 years (started in 1979) I can tell you this is not quite true. In most aircraft operations the altimeter in the plane is set for the barometric pressure of the airport. This results in the altimeter showing an altitude of zero while on the ground at that airport. (technically it’s height, not altitude). An altimeter is basically a very sensitive and calibrated barometer. Even though that particular airport may have an elevation of 2000 feet compared to sea level, the important thing to the pilot is how far above the ground they are. While enroute the accuracy of the altimeter will vary. When arriving at the landing point the pilot is advised of the barometer reading at that airport and the altimeter is adjusted to the proper setting for that airport so while landing they know how far they are above that runway.
A pilot needs to know AGL (above ground level) much more than they need to know AMSL (above mean sea level). This is why setting the altimeter before takeoff and landing is critical. You need to know the height above ground of any obstructions around the airport — trees, power lines, buildings, mountains (!) etc. You don’t give a crap about sea level. When departing or arriving at an airport you need to fly the proper hight above ground — this information is provided in AGL by the airport, e.g. downwind leg at 1000, final at 500 feet, etc.
If a plane is flying at 5000 feet in nearly all cases that is referring to above ground level. This of course varies in the commercial airline world, but those planes also know where they are in reference to sea level and above ground.
And of course a signal to an aircraft is straight one with no obstructions, and no ground effects, etc. The typical antenna with most transmitters is also not a focused or “gain” antenna. That’s part of the concept of a gain antenna. A 100,000 watt FM station doesn’t develop 100,000 watts in the transmitter, they may put out 20,000 and the rest is created with a gain type antenna which basically focuses the signal horizontally so no signal is wasted going “up” while the population is “out”. A rubber duck or hunk of wire on a Part 15 transmitter has no gain and the signal goes everywhere.
But the line of sight from an aircraft is why pilots of vintage aircraft or basic homebuilts may not have a built in radio — heck lots of old planes don’t even have an electrical system — and the pilot can use a handheld comm radio with a rubber duck antenna to communicate with a airport as far as 10 to even 15 miles away.
TIB
I thought it was sea level referenced when quite a while back I went for a ride in a small plane that lands and takes off on a lake and he told me this.
Anyways, I got myself a scanner, not the more expensive ones but one in my price range that would cover what I needed. I set the squelch at 1 as if it was turned off completely the scanning would take forever as it would stop at any hash on every frequency. I put a better antenna on than the rubber duck BNC it came with and I was in the same room with my Decade MS-100 FM transmitter as it was operating with my station. I let it scan from 108 to 174 MHZ which is the civilian air band, police, fire, some other two way communications and the other frequency range of 406.000 to 512.000 MHZ. The ham band is in there somewhere too. Also went through the band 25-54 MHZ.
I got all kinds of interesting stuff….sometimes only 1/2 of the conversation, some airplanes as they were overhead, a few police calls looking for a hit and run driver that hit a pedestrian, couriers talking to home base, all kinds of stuff but NOT ANYTHING FROM MY TRANSMITTER. Turned off the squelch completely and manually tuned through the 108 to 174 MHZ(took a long time) and nothing from my transmitter from 10 ft away and operating at BETS-1. The sensitivity of the scanner is 0.3 uV give or take on all ranges.
I am assuming this scanner is a lot more sensitive than an older portable radio that has the public service and air bands.So it seems to jive with what the FCC agents told thelegacy about liking the Decades.
Would be interesting to see what one of the Chinese ones would do but that’s a no no as the planes are not that high flying over where I am as the Toronto airport is not that far away. And now that I know how bad they are I would never do it.
So now I have a scanner that will sit on the shelf except for some entertainment once in a while.
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