I used to live in a city with 50,000 residents in the southern U.S.. There was, and probably still is, a pirate station in the educational FM band. It has been on the air for years and it doesn't interfere with local FM signals. I have sinced moved to a town of 20,000 people in southern MN. Someone started a pirate station playing Tejano music
24 hours a day. Unfortunately their frequency was at 90.3 MHz and the signal bled over onto the local MPR signal at 90.1. I complained to the FCC and within 3 weeks they shut the station down. So it appears that the FCC is more aggressive when the station impinges on legitimate signals.
"Harmful interference" vs. "unauthorized operation". Both can come with big fines... but, yes, the FCC is somewhat more likely to react when faced with a situation where a legitimate licensed broadcaster is being interfered with. (Commercial licensees have paid $$ for their licenses, and don't like losing market-share/coverage to pirate transmitters).
I was oblivious to your requirement, you made that clear. I just wanted to let people know what I do, and to make them aware of the old radio programs available over the internet. Listening to Dragnet as I write, on an FM radio!
Mikek
btw, has anyone tried a class E amplifier as an AM transmitter? Base/gate drive is transmit frequency, B+ is the audio. I'll google it.
Bulk table salt sells for about $100 per metric ton. Methinks I'm worth more than that.
Not the way they were originally written. Hz = cycles/second. However, the original comment was "16,500 kc" which is just cycles. No way to know if that's cycles/sec, cycles/minute, cycles/fortnight, or just counting waveform cycles. If he had written "cps", which means cycles/second, I might agree, but not kc.
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Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
Aside from not being AM, I plan to give that link a listen. Sounds like fun listening to those old radio shows. (By the way, those shows were probably all broadcast on AM. FM did not exist at that time).
Thanks to all who replied. I am considering geting one of them ebay mini transmitters, but this is more to see if I can do it with the signal gen. And I have 3 of them to try. I think my Eico 315 is the most suitable though and is my best one.
Yea, I was not thinking when I typed that band number. I was thinking
1650 khz though. (just to avoid other stations from interfering). I have never known any AM stations to exist above 1600. I sort of thought all radios went to 1700, but I guess I was wrong.
Just curious, in what year did they add 1600 to 1700 to the AM band? It does seem to me that a few times I have sent a signal to one of these antique radios and gone above 1600 though, while aligning them. But I suppose it depends on the radio design and how far the tuning cap can go.
For sound quality and for stereo, a FM transmitter would be better, but most of my antique radios are only AM band.
I am not too worried about the FCC coming to "get me". First off, I live in a all metal home. Metal siding and roof. To use my cellphone I have to go outside. Secondly, I live on a farm, and the nearest neighbor is a mile away. So even if it does leak outside a little, only the deer and pesky raccoons who carry pocket radios will pick up my signal. Of course I will take a walk with a pocket radio or use my car radio just to see if it is going beyond my home, and how far.
Interestingly enough, after I posted this, I went to youtube and typed in a few words to search for this. I found that I am not the first person to attempt this. Some guy did it. He found that running a MP3 player right into the signal generator had very weak audio. He then ran the MP3 player into a stereo amp, and connected the amp's output to the signal gen. Doing that, did make a strong signal, but it was rather distorted. However, he connected the 8 ohm speaker output to the signal gen. That alone seems like an overload. I'd be more inclined to use a preamp between the signal gen and the MP3 player. Or use the "tape out" jack from on a stereo amp or receiver. (which is preamp output).
I'll play with it, and see what happens, and post the results, unless the FCC hauls me away and locks me up in some prison in Russia. (Which means I better not play any Russian music over the air). :)
I watched a youtube video about this transmitter (actually SSTRAN 5000). I thought this was a good option. I clicked on the URL you posted and it appears they are OUT OF BUSINESS. Their website says something to the extent "No new orders after November xx 2017, and new customers who already paid, will be issued a refund.......
This one is being considered........
Obtaining the inductors (coils) is that hard part for ANY transmitters. I recall haveing a tough time getting them in the late 1960s. I'm sure it's 1000 times harder now. I did get the coils and did build what was called a "Phono Transmitter" in the late 60's. It worked well. Then I took it one step further. I replaced the tube with the horizontal output tube from a TV, and upped the high voltage to around 800V. (The power supply was on a separate chassis).
At that time, I was living in a big city. Using a car radio antenna mounted about 30 ft up on a tree, I put this thing on the air. I never expected the results I got. Several neighbors said their AM radios could not get any stations, except mine. A friend who lives in the suburbs about 15 miles away, said he got my station, clear as a bell.
I got carried away and had it running about 12 hours a day. Had friends act as disk jockeys and we played a lot of the songs that were banned on the regular radio stations. We got a regular studio sound mixer and connected 3 turntables, an 8track and a reel to reel tape player, plus a few microphones. A lot of people loved the station, and wanted to know the location. But we never told that to anyone, knowing this was a pirate station and not legal.
One day a fancy car with all kinds of weird antennas on it began circling my block. I shut off the transmitter immediately. I am very sure it was the FCC, but that tree antenna was well hidden. I planned to move it to another friend's house, but we never did go back on the air. I wish I still had that transmitter. If I did, I'd down power it back to the original design.....
By the way, that thing taught me to respect electricity. I was probably
17 years old. I was tweaking the transmitter when I grabbed the plastic knob on the tuning cap, but my knuckle touched the cap itself, which was live 800VDC. I had a grounded microphone in my other hand. I was sitting on a heavy oak chair. Both myself and the chair were thrown about 12 feet away. The guy who was with me, said I walked around in a daze for a half hour and kept drinking water every few seconds. All I recall, is what looked like a bolt of lightning, when it hit me, and laying on the floor 12 ft from my bench. He said the microphone hit him in the head when I "launched". I sort of recall shutting off the switch that powered my whole bench, right after. That was one scary shock. The worse I ever got.
I did encapsule that tuning cap in a box after that, and modified that cap as well, because I used to get arcing between the plates. The original one was a common 365pf AM radio tuning cap. I remember buying a costly ceramic cap to replace it. Then building a shield around it to avoid any chance of touching it.
When I look back, that whole thing was a lot of fun, aside from that shock. A lot of people were saddened when we went off the air.
Right now is probably the PERFECT time to operate a pirate station. Since the government is shut down, the FCC is probably not doing much. NO, I am not encouraging this, just commenting......
FM radio was assigned the 42 to 50 MHz band of the spectrum in 1940. But then WWII happened. After the war, on June 27, 1945 the FCC made its decision final and allocated one hundred FM channels from 88?108 MHz.
The "Golden Age of American radio", period lasting roughly from 1930 through the 1940s, However he last network radio dramas to originate during American radio?s "Golden Age", Suspense and Yours Truly, Johnny Dollar, ended on September 30, 1962.
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"I am a river to my people."
Jeff-1.0
WA6FWi
http:foxsmercantile.com
I keep a 3000 and a 5000, and for years I distributed them at Kutztown for Phil Bolyn, the developer. In my opinion, they are the ne plus ultra of ama teur hobby AM transmitters. I will state for the record, that most (not all ) of the stuff you will find on eBay is either junk, too powereful, or too weak to be useful.
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These are often sold at Kutzown, already adapted for a stereo input. They h ave the virtue of being frequency agile, and rather simple to operate, but as-furnished, they do not allow for much signal processing. Their more expe nsive version does allow for such signal processing, as well as a considera bly extended dynamic range. It is all in accordance with what you wish to a chieve. Considering that back in the day, those transmitters were capable o f broadcasting across the full audio band, but given the need to carry, and not step on adjacent frequencies, they pretty much limited the bandwidth t o ~100 - ~5000 hz, often considerably less both ways. Whereas the receiving radios were capable of getting the entire audio bandwidth.
Note that the SSTRAN is rated at 20-20K, and after using it, other transmit ters will sound quite thin.
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