# I'm looking for an AM transmitter. Yeah, AM. **URL:** \ **Category:** In My Humble Opinion\ **Created:** [July 9, 2019, 4:46pm UTC](https://boards.straightdope.com/t/im-looking-for-an-am-transmitter-yeah-am/836785 "2019-07-09T16:46:20Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![Translucent\_Daydream](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/translucent_daydream/32/16170_2.png) [@Translucent\_Daydream](https://boards.straightdope.com/u/Translucent_Daydream)\ **Post date:** [July 9, 2019, 4:46pm UTC](https://boards.straightdope.com/t/im-looking-for-an-am-transmitter-yeah-am/836785/1 "2019-07-09T16:46:20Z")
I have a really nice old Sony portable radio from the late 60s that works great. Where I moved, there isn’t anything other than some foaming mouth jerks on AM radio. I would like to be able to hook up a transmitter to my house stereo to broadcast my cds, tapes, and records onto the little portable Sony AM radio I have so I can listen to that stuff in the garage where I am working on a car or whatever. When I go to look up something that might work for that, I get autocorrected to FM transmitter. I want an AM one. Anyone ever have one of these or know of some? Thanks, TD ---
**Author:** ![ftg](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ftg/32/2801_2.png) [@ftg](https://boards.straightdope.com/u/ftg)\ **Post date:** [July 9, 2019, 5:35pm UTC](https://boards.straightdope.com/t/im-looking-for-an-am-transmitter-yeah-am/836785/2 "2019-07-09T17:35:15Z")
There’s some stuff on eBay. Search term AM transmitter. The cheapest option is a kit. [Example](https://www.ebay.com/itm/531-to-1602-kHz-Low-power-AM-PLL-transmitter-kit-for-learning/153545935487). If you want something prebuilt and better quality, it’ll cost [more](https://www.ebay.com/itm/800-1000-1200-KHZ-LOW-POWER-AM-RADIO-TRANSMITTER-FOR-YOUR-VINTAGE-RADIOS/333077218988). Yeah, stuff from Thailand, Turkey, etc. ---
**Author:** ![Napier](https://avatars.discourse-cdn.com/v4/letter/n/ce73a5/32.png) [@Napier](https://boards.straightdope.com/u/Napier)\ **Post date:** [July 9, 2019, 9:33pm UTC](https://boards.straightdope.com/t/im-looking-for-an-am-transmitter-yeah-am/836785/3 "2019-07-09T21:33:25Z")
Isn’t it illegal to broadcast on that band without a license? ---
**Author:** ![filmore](https://avatars.discourse-cdn.com/v4/letter/f/7993a0/32.png) [@filmore](https://boards.straightdope.com/u/filmore)\ **Post date:** [July 9, 2019, 9:43pm UTC](https://boards.straightdope.com/t/im-looking-for-an-am-transmitter-yeah-am/836785/4 "2019-07-09T21:43:35Z")
Have you ever used a consumer-grade radio transmitter? I’ve tried some FM transmitters and they really aren’t that great. The power typically is pretty weak. Even in the car where the antenna is just a few feet away, the reception is not all that reliable. From what I’ve experienced, an FM transmitter won’t be useful even if you had an FM radio. I don’t know if AM would be any different. The modern solution to your situation is to get a bluetooth transmitter for your stereo and get a bluetooth speaker for your garage. ---
**Author:** ![kenobi\_65](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/kenobi_65/32/13178_2.png) [@kenobi\_65](https://boards.straightdope.com/u/kenobi_65)\ **Post date:** [July 9, 2019, 9:49pm UTC](https://boards.straightdope.com/t/im-looking-for-an-am-transmitter-yeah-am/836785/5 "2019-07-09T21:49:52Z")
> [@Napier](#): > > Isn’t it illegal to broadcast on that band without a license? Possibly? I’m not an expert on the topic (and IANAL), but it sounds like there are those who’ve argued that, under the FCC’s “Part 15” rules, if an AM transmission is 100 milliwatts or under, it might not require a license. (Note that the assembled small transmitter to which **ftg** linked on eBay calls out that its signal strength is, in fact, 100 milliwatts.) Relevant Wikipedia links: > **[AM broadcasting | Microbroadcasting](https://en.wikipedia.org/wiki/AM_broadcasting#Microbroadcasting)** > > Some microbroadcasters, especially those in the United States operating under the FCC's Part 15 rules, and pirate radio operators on mediumwave and shortwave, achieve greater range than possible on the FM band. On mediumwave these stations often transmit on 1610 kHz to 1710 kHz. Hobbyists also use low-power AM (LPAM) transmitters to provide programming for vintage radio equipment in areas where AM programming is not widely available or does not carry programming the listener desires; in such > **[Title 47 CFR Part 15 | Unlicensed broadcasting](https://en.wikipedia.org/wiki/Title_47_CFR_Part_15#Unlicensed_broadcasting)** > > On the standard AM broadcast band, under 15.219, transmission power is limited by 100 milliwatts of DC input power to the final RF stage (with restrictions on size, height of, and type of antenna), or alternatively, under 15.221, if the AM transmission originates on the campus of an educational institution, the transmission can theoretically be any power so long as it does not exceed the field strength limits stated in 15.209 at the perimeter of the campus, 24,000/fkHz μV/m. > Unlicensed broadcast... ---
**Author:** ![Translucent\_Daydream](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/translucent_daydream/32/16170_2.png) [@Translucent\_Daydream](https://boards.straightdope.com/u/Translucent_Daydream)\ **Post date:** [July 9, 2019, 9:54pm UTC](https://boards.straightdope.com/t/im-looking-for-an-am-transmitter-yeah-am/836785/6 "2019-07-09T21:54:24Z")
> [@filmore](#): > > Have you ever used a consumer-grade radio transmitter? I’ve tried some FM transmitters and they really aren’t that great. The power typically is pretty weak. Even in the car where the antenna is just a few feet away, the reception is not all that reliable. From what I’ve experienced, an FM transmitter won’t be useful even if you had an FM radio. I don’t know if AM would be any different. > > The modern solution to your situation is to get a bluetooth transmitter for your stereo and get a bluetooth speaker for your garage. Yeah I was thinking about the whole bluetooth thing, but I would still need to modulate the signal out of the blue tooth transmitter to AM somehow. The whole fun of the AM deal was that I rebuilt the Sony AM radio to look like it was brand new, and I wanted to be able to use it. Imagine, an AM radio playing Rusted Root or something that decidedly isn’t AM radio material. I was hoping that I could pump a couple watts of AM from the second story of my house and pick it up in the yard and in the garage and what not. I was looking into a carrier station, which uses the power lines in your house to broadcast AM. Its supposed to be able to be picked up from 200 feet of a power line, and its legal to operate without a license since the transformer at the street kills the signal, but when I asked around at the local AV store for something they looked at me like I was a crazy two headed person. [Here is information on carrier radio stations.](https://www.fcc.gov/media/radio/low-power-radio-general-information) > [@](#): > > Carrier Current and Campus Radio Stations > > Carrier Current stations and Campus Radio stations do not require a license to set up and operate. A carrier current station consists of an AM radiofrequency signal on a frequency between 535 and 1705 kHz injected into a power line. The effective service range of a carrier current station is approximately 200 feet (61 meters) from the power line; however, a carrier current signal will not pass through a utility transformer. Campus Radio stations may be operated on the campuses of educational institutions provided that such operation is not within the service contour of any AM station on the same frequency, and the emission field strength complies with the limits in Section 15.221 on the campus and at the campus’ perimeter. > > Carrier Current and Campus Radio Stations are governed by 47 CFR Sections 15.207(c), 15.209(a), and 15.221 of the Commission’s rules. For more information on Carrier Current or Campus Radio Stations, please see OET Bulletin No. 63 (“Understanding the FCC Regulations for Low-Power, Non-Licensed Transmitters”). (See also the First Report and Order in GEN Docket 87-389, FCC 89-103 (1989) at paragraphs 128-129, as modified by the Memorandum Opinion and Order, GEN Docket 87-389, FCC 90-404 (1990).) ---
**Author:** ![Doctor\_Jackson](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/doctor_jackson/32/32_2.png) [@Doctor\_Jackson](https://boards.straightdope.com/u/Doctor_Jackson)\ **Post date:** [July 10, 2019, 7:46pm UTC](https://boards.straightdope.com/t/im-looking-for-an-am-transmitter-yeah-am/836785/7 "2019-07-10T19:46:45Z")
Maybe I’m missing the spirit of the thread here, but wouldn’t it be cheaper just to get cd/tape player for the garage? ---
**Author:** ![Translucent\_Daydream](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/translucent_daydream/32/16170_2.png) [@Translucent\_Daydream](https://boards.straightdope.com/u/Translucent_Daydream)\ **Post date:** [July 10, 2019, 7:57pm UTC](https://boards.straightdope.com/t/im-looking-for-an-am-transmitter-yeah-am/836785/8 "2019-07-10T19:57:29Z")
> [@Doctor\_Jackson](#): > > Maybe I’m missing the spirit of the thread here, but wouldn’t it be cheaper just to get cd/tape player for the garage? Oh man, I know that is the logical answer here, but I put in lots of hours on the restoration of this little radio. It works like it is brand new. I even repainted the dial and polished the leather that wraps the unit. When I was in Oregon, there was still options on the AM dial that were palatable, but here at the Colorado/Utah border, you can imagine what gets screamed into a microphone on the AM dial. The last time I turned it on, there was a guy that was screaming into the radio “Obama HUSSEIN’s Mooslim conspiracy to execute good Christians in the street in full sight of God and set up SHA-RA-RA LAW” and I had to shut it off again. I can’t even get a damn baseball game, major or minor league on the damn thing. If I had a decent AM transmitter, I could show people what I spent hours doing. I know its stupid. Most things I do are stupid I guess. :smack: ---
**Author:** ![HelenGawn](https://avatars.discourse-cdn.com/v4/letter/h/a88e4f/32.png) [@HelenGawn](https://boards.straightdope.com/u/HelenGawn)\ **Post date:** [July 10, 2019, 9:19pm UTC](https://boards.straightdope.com/t/im-looking-for-an-am-transmitter-yeah-am/836785/9 "2019-07-10T21:19:39Z")
[How handy are you?](https://www.instructables.com/id/Build-a-very-simple-AM-Transmitter/) There’s probably a better solution on that site, maybe build right into the radio, if you knew what to search for. That is, unless you really want the transmit-receive experience. ---
**Author:** ![HelenGawn](https://avatars.discourse-cdn.com/v4/letter/h/a88e4f/32.png) [@HelenGawn](https://boards.straightdope.com/u/HelenGawn)\ **Post date:** [July 10, 2019, 9:25pm UTC](https://boards.straightdope.com/t/im-looking-for-an-am-transmitter-yeah-am/836785/10 "2019-07-10T21:25:13Z")
_(too late to edit)_ On closer inspection, there’s not much beyond a picture in the instructable itself, but the comments or a similar search will help. ---
**Author:** ![HelenGawn](https://avatars.discourse-cdn.com/v4/letter/h/a88e4f/32.png) [@HelenGawn](https://boards.straightdope.com/u/HelenGawn)\ **Post date:** [July 10, 2019, 9:26pm UTC](https://boards.straightdope.com/t/im-looking-for-an-am-transmitter-yeah-am/836785/11 "2019-07-10T21:26:22Z")
And lastly, isn’t SHA-RA-RA that group that closed at Woodstock? ---
**Author:** ![Doctor\_Jackson](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/doctor_jackson/32/32_2.png) [@Doctor\_Jackson](https://boards.straightdope.com/u/Doctor_Jackson)\ **Post date:** [July 11, 2019, 1:45pm UTC](https://boards.straightdope.com/t/im-looking-for-an-am-transmitter-yeah-am/836785/12 "2019-07-11T13:45:49Z")
> [@Translucent\_Daydream](#): > > Oh man, I know that is the logical answer here, but I put in lots of hours on the restoration of this little radio. It works like it is brand new. I even repainted the dial and polished the leather that wraps the unit. When I was in Oregon, there was still options on the AM dial that were palatable, but here at the Colorado/Utah border, you can imagine what gets screamed into a microphone on the AM dial. > > The last time I turned it on, there was a guy that was screaming into the radio “Obama HUSSEIN’s Mooslim conspiracy to execute good Christians in the street in full sight of God and set up SHA-RA-RA LAW” and I had to shut it off again. I can’t even get a damn baseball game, major or minor league on the damn thing. > > If I had a decent AM transmitter, I could show people what I spent hours doing. I know its stupid. Most things I do are stupid I guess. :smack: Not stupid at all, I figured there was an underlying reason for taking that particular route. Makes good sense to me. The cheaper, easier option ain’t always the way to go! ---
**Author:** ![Mollie\_Magill](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mollie_magill/32/20882_2.png) [@Mollie\_Magill](https://boards.straightdope.com/u/Mollie_Magill)\ **Post date:** [July 11, 2019, 2:46pm UTC](https://boards.straightdope.com/t/im-looking-for-an-am-transmitter-yeah-am/836785/13 "2019-07-11T14:46:29Z")
I found [this site](http://lowpowerradio.blogspot.com/2011/04/low-power-broadcasting-with-carrier.html) which may help. They have links to schematics for carrier current transmitters. ---
**Author:** ![DPRK](https://avatars.discourse-cdn.com/v4/letter/d/4491bb/32.png) [@DPRK](https://boards.straightdope.com/u/DPRK)\ **Post date:** [July 11, 2019, 3:06pm UTC](https://boards.straightdope.com/t/im-looking-for-an-am-transmitter-yeah-am/836785/14 "2019-07-11T15:06:29Z")
_Are_ you handy? Get yourself a Raspberry Pi (cheap single-board hobbyist computer), download [this software](https://www.rtl-sdr.com/transmitting-fm-am-ssb-sstv-and-fsq-with-just-a-raspberry-pi/), plug in an antenna, load up the SD card with music and transmit away. Caveat, you’ll have to know what you are doing to set up the transmitter program and figure out how to pipe music to it. Furthermore, the signal is generated by turning a voltage on and off so you must know how to select an appropriate transmission frequency (OK, this will probably be the commercial AM band) and solder up an appropriate band-pass filter, otherwise you will be spamming the entire radio spectrum with unwanted interference, which is not cool, even at 100 milliwatts. ---
**Author:** ![whitetho](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/whitetho/32/1059_2.png) [@whitetho](https://boards.straightdope.com/u/whitetho)\ **Post date:** [July 11, 2019, 3:27pm UTC](https://boards.straightdope.com/t/im-looking-for-an-am-transmitter-yeah-am/836785/15 "2019-07-11T15:27:24Z")
I don’t think you want to set up a carrier current system, which covers a larger area than you need and is more complicated to set up. What you need is more along the lines of a “talking house” transmitter, commonly used in real estate to provide information for house hunters driving by individual properties. I don’t have any personal experience with the devices, but the following link has information on one particular unit: > **[Amazon.com: InfOspot AM Radio Transmitter (Talking House) : Electronics](https://www.amazon.com/Talking-House-AM-Radio-Transmitter/dp/B00XV97XZW)** > > Amazon.com: InfOspot AM Radio Transmitter (Talking House) : Electronics ---
**Author:** ![Projammer](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/projammer/32/559_2.png) [@Projammer](https://boards.straightdope.com/u/Projammer)\ **Post date:** [July 11, 2019, 4:14pm UTC](https://boards.straightdope.com/t/im-looking-for-an-am-transmitter-yeah-am/836785/16 "2019-07-11T16:14:56Z")
I found the [direct link](http://www.talkinghouse.com/) to that unit before I finished reading the thread. Quite a bit more information available there. There’s even an upgrade option to “internal component enhancement yields increased dynamic range and modulation levels. The resulting signal is even louder, fuller and more natural sounding.” ---
**Author:** ![ftg](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ftg/32/2801_2.png) [@ftg](https://boards.straightdope.com/u/ftg)\ **Post date:** [July 11, 2019, 5:43pm UTC](https://boards.straightdope.com/t/im-looking-for-an-am-transmitter-yeah-am/836785/17 "2019-07-11T17:43:12Z")
> [@whitetho](#): > > I don’t think you want to set up a carrier current system, which covers a larger area than you need and is more complicated to set up. What you need is more along the lines of a “talking house” transmitter, commonly used in real estate to provide information for house hunters driving by individual properties. > > I don’t have any personal experience with the devices, but the following link has information on one particular unit: > [https://www.amazon.com/Talking-House-AM-Radio-Transmitter/dp/B00XV97XZW](https://www.amazon.com/Talking-House-AM-Radio-Transmitter/dp/B00XV97XZW) I saw some of those listed on eBay when I did my search. Didn’t pay much attentions since I assumed they did limited messaging. But if they have an aux in, selectable frequency, etc. then they are an interesting idea. Can be had used for less than $40. Then thing **Maus Magill** points to is going to have atrocious audio quality (even by such AM hacks) and other issues. And the Raspberry Pi software radio needs a really good filter. It will generate a square wave which will be seen as noise to a lot of devices. ---
**Author:** ![That\_Don\_Guy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/that_don_guy/32/538_2.png) [@That\_Don\_Guy](https://boards.straightdope.com/u/That_Don_Guy)\ **Post date:** [July 11, 2019, 7:31pm UTC](https://boards.straightdope.com/t/im-looking-for-an-am-transmitter-yeah-am/836785/18 "2019-07-11T19:31:55Z")
> [@Napier](#): > > Isn’t it illegal to broadcast on that band without a license? Not according to [Title 47, Section 15.219 of the Code of Federal Regulations](https://www.ecfr.gov/cgi-bin/text-idx?SID=31a9820aca28a4bd0af9efbee2d51f28&mc=true&node=se47.1.15_1219&rgn=div8) ---
**Author:** ![Translucent\_Daydream](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/translucent_daydream/32/16170_2.png) [@Translucent\_Daydream](https://boards.straightdope.com/u/Translucent_Daydream)\ **Post date:** [July 11, 2019, 10:59pm UTC](https://boards.straightdope.com/t/im-looking-for-an-am-transmitter-yeah-am/836785/19 "2019-07-11T22:59:49Z")
I think that maybe the Talking House with the upgrade (which is essentially a compressor to level the sound and pump some gain) is probably the easiest way to go. Plus it kinda looks like I could put that into my component stereo system, and it has the whole VCR vibe to it. I am still really interested in doing the carrier current thing though, just to see if I could pull it off. The schematic doesn’t look THAT complicated… but I am unsure about winding my own transformers. ---
**Author:** ![Kent\_Clark](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/kent_clark/32/105_2.png) [@Kent\_Clark](https://boards.straightdope.com/u/Kent_Clark)\ **Post date:** [July 13, 2019, 2:02am UTC](https://boards.straightdope.com/t/im-looking-for-an-am-transmitter-yeah-am/836785/20 "2019-07-13T02:02:49Z")
> [@Napier](#): > > Isn’t it illegal to broadcast on that band without a license? Not at the power those things put out, although you have to “accept interference” from other equipment, radio stations, or just static. As an old AM radio guy, I really think you’d be better off with a Bluetooth transmitter and a cheap BT speaker. [Next page](https://boards.straightdope.com/t/im-looking-for-an-am-transmitter-yeah-am/836785.md?page=2)