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LRN.FM - The Liberty Radio Network => Free Radio Forum => Topic started by: FTL_Ian on December 30, 2008, 02:19:11 PM

Title: Where to find "real" transmitters (and antennas) for FM and AM.
Post by: FTL_Ian on December 30, 2008, 02:19:11 PM
Remember to check ebay for deals on these products:


30 Watt, super affordable
http://fmuser.com/low-power-fm-transmitter/030W-V20-PLL-Professional-FM-transmitter-1U-87108Mhz-New-Arrival.html (http://fmuser.com/low-power-fm-transmitter/030W-V20-PLL-Professional-FM-transmitter-1U-87108Mhz-New-Arrival.html)


50 Watt Professional FM Transmitter
http://www.ramseyelectronics.com/cgi-bin/commerce.exe?preadd=action&key=PX50 (http://www.ramseyelectronics.com/cgi-bin/commerce.exe?preadd=action&key=PX50)  (This is a slick unit.)

1/2 Wave Antenna - easy to tune!
http://fmuser.com/antenna/Fmuser-DP100-12-Half-Wave-FM-Dipole-Antenna-High-gain-outdoor-Dipole-antenna-88-to-108mhz-for-FM-Transmitter-up-to-150w8M-Feeder-Cable.html (http://fmuser.com/antenna/Fmuser-DP100-12-Half-Wave-FM-Dipole-Antenna-High-gain-outdoor-Dipole-antenna-88-to-108mhz-for-FM-Transmitter-up-to-150w8M-Feeder-Cable.html)


5/8 Wave Antenna (handles up to 200W)
http://www.ramseyelectronics.com/cgi-bin/commerce.exe?preadd=action&key=FMA200 (http://www.ramseyelectronics.com/cgi-bin/commerce.exe?preadd=action&key=FMA200)

Lots of choices here:
http://transmittersrus.com/fmtransmitters.htm (http://transmittersrus.com/fmtransmitters.htm)  (FM)
http://transmittersrus.com/tru/rpg80mw_overview.htm (http://transmittersrus.com/tru/rpg80mw_overview.htm) (AM)

http://www.nicomusa.com/fm.html (http://www.nicomusa.com/fm.html)  


http://www.pcs-electronics.com/ (http://www.pcs-electronics.com/) (variety of packages and transmitters - looks like good quality)

Looks like Free Radio Berkeley is making a variety of transmitters.  Not sure of the build quality, doesn't look like professional audio connectors:
http://www.freeradio.org/index.php?pagename=store/transmitter.html (http://www.freeradio.org/index.php?pagename=store/transmitter.html)

Am I missing any good sources?
Title: Re: Where to find "real" transmitters (and antennas) for FM and AM.
Post by: FTL_Ian on December 30, 2008, 03:37:12 PM
Low-loss LMR-400 cable (for between your transmitter and antenna), custom made:

http://www.jefatech.com/product/ll400
Title: Re: Where to find "real" transmitters (and antennas) for FM and AM.
Post by: FTL_Ian on December 31, 2008, 12:09:11 PM
I found the manufacturer of the 80W AM transmitter that transmittersrus sells on  selling his own units on ebay.  He gave me his website:


Looks like he makes a variety of AM and FM transmitters:
http://www.pll.gr/d.htm
Title: Re: Where to find "real" transmitters (and antennas) for FM and AM.
Post by: conrad from spain on January 12, 2009, 07:57:58 PM
The 50 Watt Ramsey transmitter can be sold in a kit that can be used right out of the box. This kit is a bit pricey though but I've heard it sounds great. Some islands in the Carribean use these to broadcast to the whole island.

http://www.tequipment.net/RamseyElectronicsPXB50.html

This kit comes with:

      50 watt FM Stereo Transmitter

      Integrated CD Player
      Integrated Cassette Player
      Built In Audio Mixer
      Professional Microphone and Cables
      Omni directional 3.4db Gain Antenna and Coax

      Installed and prewired in a high impact road case!

With a 3.4 db gain antenna you get more than twice the radiated power (like having a 100 watt transmitter).

This will give you a really good stereo FM signal! It could be portable on a car battery too.

Maybe the CD player and cassette recorder are extra if you're going to get your audio from a computer. However with this kit you are able to transmit as soon as you get the box (just set up the antenna and the cables).

Remember the higher elevation your antenna, the more range that you get.

I used to transmit off a smaller Ramsey kit in college and had pretty good results with a homemade antenna made out of copper welding rods. When I change to a 5/8's wave I got a much better signal and range.

Here's a good FAQ about setting up a transmitter:

http://www.faqs.org/faqs/radio/broadcasting/low-power-faq/
Title: Re: Where to find "real" transmitters (and antennas) for FM and AM.
Post by: sinceredagreat on January 12, 2009, 08:20:20 PM
Here's one. Works pretty good.

(http://www.armyproperty.com/Equipment-Info/Pictures/Sincgars.jpg)

One of the radios I used to work on.
Title: Re: Where to find "real" transmitters (and antennas) for FM and AM.
Post by: FTL_Ian on January 13, 2009, 11:30:34 AM
You'd have to be mad to buy that package.  Just get the transmitter and 5/8 wave.  All you need then is the appropriate length of cable, plus your audio source.
Title: Re: Where to find "real" transmitters (and antennas) for FM and AM.
Post by: kalmia on April 13, 2009, 01:33:52 PM
Here's one. Works pretty good.

(http://www.armyproperty.com/Equipment-Info/Pictures/Sincgars.jpg)

One of the radios I used to work on.

Steal me one from the military.
Title: Re: Where to find "real" transmitters (and antennas) for FM and AM.
Post by: Incognitum on June 02, 2009, 10:05:12 AM
Has anyone used the HLLY transmitters?  Very cheep (5W ~$100, 20W ~$200) but I would be interested to hear if anyone can report on the quality.

These transmitters show up on ebay every now and again, or can be bought direct from http://www.hllyelectronics.com (http://www.hllyelectronics.com)
Title: Re: Where to find "real" transmitters (and antennas) for FM and AM.
Post by: sillyperson on June 02, 2009, 12:39:25 PM
The call the other night from the Liberty Radio 1710 guy was really interesting -- if I can legally broadcast even 2-3 miles, I can get a good swathe of Manchester.
http://www.libertyradio1710.com/

If I can get some more info & specifics, I'll be setting up an antenna in Manchester(*)  8)



(*) in a few months once some other projects have calmed down!
Title: Re: Where to find "real" transmitters (and antennas) for FM and AM.
Post by: FTL_Ian on June 02, 2009, 04:45:12 PM
The call the other night from the Liberty Radio 1710 guy was really interesting -- if I can legally broadcast even 2-3 miles, I can get a good swathe of Manchester.
http://www.libertyradio1710.com/

If I can get some more info & specifics, I'll be setting up an antenna in Manchester(*)  8)



(*) in a few months once some other projects have calmed down!

He was using the rangemaster.
Title: Re: Where to find "real" transmitters (and antennas) for FM and AM.
Post by: marknh on July 08, 2009, 02:03:24 AM
ramsey is pretty much junk.
nicom is good. :)

http://www.panaxis.com/
http://www.progressive-concepts.com/info/item.html?class=fm%20transmitters
http://www.veronica-kits.co.uk/

a simple 1/4 wave antenna does work very well.
Title: Re: Where to find "real" transmitters (and antennas) for FM and AM.
Post by: FTL_Ian on January 26, 2010, 10:53:53 PM
Has anyone used the HLLY transmitters?  Very cheep (5W ~$100, 20W ~$200) but I would be interested to hear if anyone can report on the quality.

These transmitters show up on ebay every now and again, or can be bought direct from http://www.hllyelectronics.com (http://www.hllyelectronics.com)

Make sure you use a low-pass filter - I'm not sure units that cheap have them.  Make sure they do, otherwise you can get one to add between the transmitter and antenna.
Title: Re: Where to find "real" transmitters (and antennas) for FM and AM.
Post by: Low-Eight on January 27, 2010, 03:46:16 AM
Here's one. Works pretty good.

(http://www.armyproperty.com/Equipment-Info/Pictures/Sincgars.jpg)

One of the radios I used to work on.

It would appear that this only works up to 88mhz, which is the low end of the radio dial. . .
Title: Re: Where to find "real" transmitters (and antennas) for FM and AM.
Post by: KDus on January 28, 2010, 11:29:42 PM
The Ramsey FM100B is a good deal. It sounds pretty good and is stable and clean. I built one for a friend and he used it for a couple years. He brought it for me to fix and I found a penny and a paper clip inside. I cleaned it up and it still works well. I did modify it with an external antenna port so we could run a small amp. It doesn't want to be driven hard.

The pcs-electronics CYBER MAX boxes are a good buy, too. They're modular so you can mix and match parts. They even have an RDS board you can pop in there. I modified one of those with a PL-259 connector and a cooling fan upgrade. They have several adjustments so you can just buy the boards you want, or a whole package.
The built in compressor might be OK for talk, but it was pathetic for music.

If you want REAL equipment, google: Broadcast Electronics, Harris, Collins, Armstrong, Marti (low-end), Crown, QEI (low-end)
REAL antennas are made by ERI, Scala, Cellwave, Harris,  Shively, Jampro("junkpro", Kathrein
Title: Re: Where to find "real" transmitters (and antennas) for FM and AM.
Post by: KDus on June 11, 2010, 11:03:06 PM
Been helping a friend with a part 15 AM. He bought a package from iamradio.net

So far, the results are terrible. This guy built a respectible studio and did everything right but only gets a couple hundred yards. If I can solve the problem, he should get a couple miles.
If I can't fix it, I'll suggest he gets his money back and buys a rangemaster.
Title: Re: Where to find "real" transmitters (and antennas) for FM and AM.
Post by: RFBurns on September 04, 2010, 09:57:26 AM
Has anyone used the HLLY transmitters?  Very cheep (5W ~$100, 20W ~$200) but I would be interested to hear if anyone can report on the quality.

These transmitters show up on ebay every now and again, or can be bought direct from http://www.hllyelectronics.com (http://www.hllyelectronics.com)

Make sure you use a low-pass filter - I'm not sure units that cheap have them.  Make sure they do, otherwise you can get one to add between the transmitter and antenna.


The HLLY units (also labeled as CZH-##) do in fact have an internal output filters (3 pole) on all of the models. It is located behind the heat sink near the internal fan connector. They are properly tuned from the factory to cover the entire FM band, but they can be peaked to a specific frequency to improve their performance by simply separating the coil windings or compressing them or combination.

A spec-an is highly recommended to properly adjust these or any other filter.


RFB
Title: Re: Where to find "real" transmitters (and antennas) for FM and AM.
Post by: FTL_Ian on September 04, 2010, 12:48:07 PM
I am surprised to find that out.  Welcome to the forum and thanks for the expertise. 

For the record, here is HLLY's official response to my question about which of their transmitters have low-pass filters:

http://www.hllyelectronics.com/forums/index.php?action=vthread&forum=1&topic=346
Quote
TX-30S, TX-01S, HLLY 20W Fm transmitter all have good low-pass filters!
Title: Re: Where to find "real" transmitters (and antennas) for FM and AM.
Post by: RFBurns on September 04, 2010, 09:48:05 PM
Thank you for the welcome. :)

Thats great they actually provided info! The "CZH" units, I had to practically claw and fight for information. 2 months after purchasing the CZH-5 and CZH-20, the HLLY units started showing up on ebay. Curiosity got the best of me because the HLLY units appeared to be identical to the CZH units...as far as the case styles and front pannel controls.

So I bought 2 of the HLLY units, same power levels of 1/5 watt selectable unit and the 20w unit. Once they arrived I opened them up and put them side by side to the CZH units.

Identical boards in both brands. Some of their lower power units wont have any filtering, but its advisable to buy one or home brew a filter for those.

RFB
Title: Re: Where to find "real" transmitters (and antennas) for FM and AM.
Post by: FTL_Ian on October 09, 2010, 10:01:04 PM
Our new station in Ohio is using a TX from http://fmuser.com/
Title: Re: Where to find "real" transmitters (and antennas) for FM and AM.
Post by: RFBurns on October 21, 2010, 11:22:35 AM
Our new station in Ohio is using a TX from http://fmuser.com/

As you can see on the FMuser site, there is a CZH unit (black case) pictured with the silver units.

These units can be set to operate in two power modes. 1.5w and 5w (typical 7w). These can also be set so that if the power goes out and returns, you dont have to re-set your operating frequency. Simply program the unit's upper and lower frequency range to your operating freq.

1. Hold power button on while plugging the power source into the power jack.

2. Display will show either an "L" or an "H". L for low power, H for high power. Use the + or - keys to set, push the power button to go to the next setup sequence...frequency range.

3. The unit will start at its upper frequency setting from the factory. *NOTE: These units CAN transmit well above 108 Mhz and well below 88 Mhz so be careful!! Set the unit's upper frequency limit, then push the power button to go to the low frequency limit.

4. Set the low frequency limit and push the power button. The unit will store the settings and power off.

During these setup stages, the unit will not be transmitting, however it is always safe to attach a dummy load to the output when going into the setup/power modes.

They are great little units with excellent performance for the price.


RFB
Title: Re: Where to find "real" transmitters (and antennas) for FM and AM.
Post by: FTL_Ian on November 23, 2010, 10:45:19 PM
Wow, useful tip!   8)
Title: Re: Where to find "real" transmitters (and antennas) for FM and AM.
Post by: RFBurns on January 25, 2011, 03:54:49 AM
Wow, useful tip!   8)

The later models of the 15 and 20 watt units can also be set for low and high power. These two units are really great for driving large power amplifiers.

I used one as a temporary exciter to drive a Harris FM-25 transmitter. The Harris FM-25 is a 25Kw power amp cabinet that only needs about 15 watts to make full power on the lower third of the band.

The station is KMLD 94.5 in Casper Wy.
Title: Re: Where to find "real" transmitters (and antennas) for FM and AM.
Post by: yanni cash on July 21, 2011, 08:59:20 PM
free radio berkely is bad news. heads up.
Title: Re: Where to find "real" transmitters (and antennas) for FM and AM.
Post by: KDus on August 06, 2011, 11:31:57 PM
Wow, useful tip!   8)

The later models of the 15 and 20 watt units can also be set for low and high power. These two units are really great for driving large power amplifiers.

I used one as a temporary exciter to drive a Harris FM-25 transmitter. The Harris FM-25 is a 25Kw power amp cabinet that only needs about 15 watts to make full power on the lower third of the band.

The station is KMLD 94.5 in Casper Wy.
Do they have remote control I/O for muting, APC, failsafe and such?
Title: Re: Where to find "real" transmitters (and antennas) for FM and AM.
Post by: humpower on February 18, 2014, 01:40:31 AM
You'd have to be mad to buy that package.  Just get the transmitter and 5/8 wave.  All you need then is the appropriate length of cable, plus your audio source.

Yes,can't agree with u more. One transmitter ,and cable and antenna make it a complete broadcasting system.
For 10W FM professional transmitter ,i recommend as below for your choice:
http://www.hcfmtv.com/professional-fm-transmitter/ (http://www.hcfmtv.com/professional-fm-transmitter/)
Title: Re: Where to find "real" transmitters (and antennas) for FM and AM.
Post by: humpower on February 25, 2014, 01:16:16 AM
You'd have to be mad to buy that package.  Just get the transmitter and 5/8 wave.  All you need then is the appropriate length of cable, plus your audio source.

Yes,can't agree with u more. One transmitter ,and cable and antenna make it a complete broadcasting system.
For 10W FM professional transmitter ,i recommend as below for your choice:
http://www.hcfmtv.com/professional-fm-transmitter/ (http://www.hcfmtv.com/professional-fm-transmitter/)

the link i recommend is from factory direct sale, with low price.