[BC] LPAM transmitters and antennas

[Tom Spencer]

Scott Bailey wrote:
>Now I will have to say, for a Part 15 Transmittter, those little Rangemasters get out and they sound just as good as the Nautel's, BE's, etc.  I have talked to Keith Hamilton before on the phone and I was trying to get him to build us a little 3-5 watt transmitter. If we had a tornado rip through this town and I lost the station, I could get back on the air in the middle of town with a Rangemaster and a good whip antenna until I got in new gear.
>
>Since LPB is gone, there is nobody that I know of that makes a "Low Power", Solid State AM transmitter that is in the U.S. I saw some on ebay made in Greece, but I just don't like buying gear from another company outside the U.S.

Radio Systems makes the "Talking House" 100 mW units; out of the box, they get about 500 ft; you can get a souped-up antenna kit that will increase that ;; they claim between a half-mile and a mile, IIRC.  They also make a 30-watt transmitter for TIS/carrier current/Campus Limited applications - the TR-6000.  I have the older version of that - the TR-20, which is crystal-set, rather than a PLL like the TR-6000, and it sounds very good; although it tends to get picky regarding its load - and the output transistors for the -20 are getting hard to find (class AB final; low level modulation).  Radio Systems also sells a TIS / Free Radiate antenna system for free-radiate applications, as well... uses the same coupler for the ATU as they use for the CC application - the CP-15.

http://www.radiosystems.com/

The TR-6000 is here

http://www.radiosystems.com/carriercurrent.html

Radio Transmitter and Coupler     $1,620.00; Antenna Package  $1,295.00 - specify desired frequency or at least what part of the band you want the antenna for; there's about four or five different versions (loading coil and tuning stub) depending on frequency.

I would note that the TR-6000 can be dialed back to about 1-watt or so, minimum; they sell it preset at 10 watts for most applications; if you want the full 30 watts, order the CC version.  BTW- this IS the same radio Systems that makes the Millennium consoles in Logan Township, NJ.

Another Part 15 - compliant transmitter is the SSTRAN AMT3000;; many Part 15 operators swear by them.

http://www.sstran.com/

They ALSO offer a souped up antenna - at least the instructions on how to build one - also claiming between a half-mile and a mile.  I'm not sure just what signal level they're using for that range estimate...

http://www.sstran.com/pages/sstran_buildant.html

Just for the sake of completeness, here's the link to the Rangemaster website:

http://www.am1000rangemaster.com/