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Author Topic: FM transmitter  (Read 3643 times)

Offline Shogun72

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FM transmitter
« on: October 03, 2016, 2221 UTC »
Anyone have a line on where to purchase a clean FM transmitter for less than $100? No cheep CZ crap. Had one of those and it bled all over the band. And burned up quick.

Offline Stretchyman

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Re: FM transmitter
« Reply #1 on: October 04, 2016, 1544 UTC »
The CK stuff (is that China?) looks fine and making an LPF is simple enough.

Did you attach it to an antenna with a known impedance i.e. a good SWR?

Hmm..... ???
'It's better to give than receive' so why RX when you can TX!

                            Buy one from me, NOW!

Great discounts on ALL my transmitters if purchased via HFUnderground


                                              ;)

Offline BDM

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Re: FM transmitter
« Reply #2 on: October 06, 2016, 2245 UTC »
I'm still using my old Panaxis FME-500. Not sure what you'll find today under $100 quality wise.
Radios -- Perseus SDR // Icom IC-7410 // Tecsun PL-660 // Panasonic RF-5000A --Antennas-- Pixel Pro 1B loop - 82' fan-dipole at 40' - tuned MW/BCB 40" loop and 100' receive only dipole
-Brian--North of Detroit--MI-
1710/KHz the MW Pirate Clear Channel (not so much anymore "sigh")

Offline Pigmeat

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Re: FM transmitter
« Reply #3 on: October 07, 2016, 0143 UTC »
The CK stuff (is that China?) looks fine and making an LPF is simple enough.

Did you attach it to an antenna with a known impedance i.e. a good SWR?

Hmm..... ???

Two things Stretchy. One their QC is all over the place. You get 15-20 watts of FM stereo cheap, but you're buying a pig in a poke. They're notorious for going pfft early and often. Two, they sell the things as "plug and play". They're not. You're going to want to add an outboard filter in most cases and junk the two meter handy-talky antenna that comes screwed in the back as a start. Then you hope it still doesn't go pfft. As they attract a lot of first timers with their low prices and plug and play pitch they're basically screwing the unknowing with their claims.

Offline redhat

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Re: FM transmitter
« Reply #4 on: October 07, 2016, 0630 UTC »
The first rig I built from plans on the internet.  It was a Veronica VFO thing, and it did drift alot.  This was about 15 years ago, total outlay for the parts was $40, made the board for it in Mom's sink (she wasn't real happy about that...)  I later moved up to a Harris MS-15 which served me well for many years.

Its too bad they want an arm/leg for old broadcast junk on ebay.  I'd rather see that stuff go to good use than in the landfill.

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Offline Stretchyman

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Re: FM transmitter
« Reply #5 on: October 07, 2016, 0632 UTC »
Thanks Mr P!

Could someone point me towards a particular popular CK FM widget so I can take a look, not REALLY a market I'd like to get into (but you never know!).

I am, however, coming to the conclusion that I should build whatever folk want and have recently tapped into a new market of the LP MW bunch who want 1W I guess similar to your 100mW M.W. lot over in U.S.

Not sure how popular that is in the States?

And how popular if FM piracy in NYC?

 ???

Str.

'It's better to give than receive' so why RX when you can TX!

                            Buy one from me, NOW!

Great discounts on ALL my transmitters if purchased via HFUnderground


                                              ;)

Offline EliteData

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Re: FM transmitter
« Reply #6 on: October 07, 2016, 1443 UTC »
...And how popular is FM piracy in NYC?
popular enough that for every commercial NYC FM station, there are 5 pirate NYC FM stations.
there are so many NYC FM pirates that there is competition between them, many of them transmit on top of each other in an effort to "block out" the other pirate, there are sometimes physical altercations between them over the little space available on the FM dial and who has the cheaper offer for advertisements and commercials.
however, it is extremely rare to find an FM pirate in NYC that is operating their equipment inside specifications that does not cause 1/2 power or more of the 2nd harmonics generated, deviation that exceeds 150Khz and generally sounding terrible overall with massive azimuth errors and background noise.
add to this that more than most of them are broadcasts that are directed at the large ethnic population (mostly in Brooklyn).
out of this huge mess of garbage, its very very unlikely that there is a "hobby" NYC FM pirate.
its not longer what it used to be years ago.


Offline EliteData

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Re: FM transmitter
« Reply #7 on: October 07, 2016, 1456 UTC »
The first rig I built from plans on the internet.  It was a Veronica VFO thing, and it did drift alot.  This was about 15 years ago, total outlay for the parts was $40, made the board for it in Mom's sink (she wasn't real happy about that...)  I later moved up to a Harris MS-15 which served me well for many years.

Its too bad they want an arm/leg for old broadcast junk on ebay.  I'd rather see that stuff go to good use than in the landfill.

+-RH
and the first one i built, was from a PLL synthesized FM broadcast radio receiver, i used a 12 volt car radio, they're easier to work on.
changing the PLL clock crystal to -100Khz to change even to odd.
tapping off the IF local oscillator mixer as the RF generator.
adding a RF LPF filter and adding modulation.
part 15 with no amplifiers added.
takes all but 30 minutes to modify and build.
built mine into a metal lunch box with a DC power jack, antenna jack and audio jack on the outside and a small stage amp inside that brought the RF power to 1 watt.
i eventually sold it to another pirate enthusiast for $100 who promptly ended the life of the device with magic smoke shortly afterwards   ;D

Offline Pigmeat

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Re: FM transmitter
« Reply #8 on: October 07, 2016, 2151 UTC »

And how popular if FM piracy in NYC?

 ???

Str.



Enough that they made it felony offense a few years back.

I can't say that I blame the powers that be. I wouldn't want to be stuck in a holding pattern in the crowded skies of greater NYC with all those crap transmitters throwing spurs across the air band.

Offline Azimuth Coordinator

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Re: FM transmitter
« Reply #9 on: October 13, 2016, 2101 UTC »
I suggest a BW Broadcast TX1  10 mw transmitter It's my main transmitter now and with a good antenna with some elevation you should get around 1/4 to 1/2 mile with a good receiver or car radio.   If your thinking about something bigger you better have a full air chain and the technical knowledge of how the keep you modulation very tight and in band or the knock on the door is just a matter of time. 


tAC
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Offline CoolAM Radio

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Re: FM transmitter
« Reply #10 on: October 21, 2016, 0159 UTC »
For many items- & options
Check:

http://www.veronica-kits.co.uk/

Andre
CoolAM Radio
http://jingleproductions.coolam.nl
   Transmitters Do It On Air!!!
::::::::::::::::::::::::::::::::::::::

Offline Rafman

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Re: FM transmitter
« Reply #11 on: December 12, 2016, 0243 UTC »
As of May 2016, there were more pirate than licensed FMs in NYC Metro MTA

Extensive article http://diymedia.net/ny-broadcasters-try-quantifying-pirates/8361

Awesome 103 page report with maps, tables, pictures, addresses & ERPs
http://diymedia.net/wordpress/wp-content/uploads/2016/07/Pirate-2016-study-final-pdf.pdf

I find it all fascinating, especially having grown up in NY-metro...

Rafman
« Last Edit: December 12, 2016, 0301 UTC by Rafman »
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