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The R139 is a very sensitive wideband fm receiver optimized for reception of NOAA APT and similar weather facsimile images on the 137 MHz band. You can use it with any popular demodulator and software.

The R139 has excellent sensitivity (0.2µV); so no preamp is needed for normal operation. Special wideband filters enable low distortion for high quality imaging, even with doppler shift on the satellite signal. Five precision crystal controlled channels cover all popular satellites.

The R139 is much lower cost and easier to maintain than synthesized units! And it is designed from the ground up for optimum satellite reception; not just an off-the-shelf scanner with a shorted-out IF filter!

Scan circuit and tape recorder control output allow you to automatically search for and record signals as satellites pass overhead, even while away from home.    

FEATURES:

• Very sensitive - 0.2 µV typical. Low-noise dual-gate FET rf amplifier and mixer.
• Wide bandwidth filters for low distortion pictures; 38 kHz modulation acceptance.
• Five channels - can manually select any satellite simply by stepping the SCAN switch on the front panel.
• Scanner circuit automatically searches for, and locks onto, any satellite signal within range. Select this mode with the AUTO position of the SCAN switch.
• Crystal controlled for frequency stability. All crystals supplied at no extra cost.
• A fraction of the price of synthesized units.
• Adjustable audio output level to drive speaker and demodulator.
• Squelch indicates when satellite is heard; can be used to start recorder. Open collector transistor output can be used directly or through a relay to turn on tape recorder.
• Complete detailed instruction manual and drawings included, something you don't get with off-the-shelf scanner radios.

SPECIFICATIONS:

• Channels supplied: 137.100, 137.500, 137.620, & 137.9125MHz NOAA APT Satellites and 137.400 Meteor.
• Size, case + knobs: 4-7/8W X 5D X 2-1/4H inches.
• Size, pcb excluding controls, connectors: 4½W x 4D in.
• Operating Power: 10-15Vdc @ 45-120 mA. (115Vac-12Vdc power adapter supplied with cabinet option.)
• RF Input connector: BNC
• Audio output: 1W (8 load). Volume and squelch controls on board.
• Power and audio connector: DB-9 (male on pcb) *
• Required for alignment: signal generator & dc voltmeter.
• Shipping weight:  2 lb.

See review in an August 1997 QST article.

See links to related websites with information and  programs you can download.

Demodulating Weather Fax Signals.

The R139 Receiver demodulates the fm signal transmitted by the weather satellite. Its 2400 Hz audio tone output must be further demodulated and converted to digital pulses, which is normally done with the sound card in your computer and imaging software.  You can download a freeware program discussed in an August 1997 QST article.

See links to related websites with information and  programs you can download.

This popular unit achieves a low noise figure (0.6 dB) with a gain of 18 dB.  Operating power is +12Vdc at 10 mA, connected through a feedthrough capacitor. The 50 input and output use BNC jacks.

The preamp is connected in series between the antenna and the receiver to effectively lower the noise figure of the receiver front end, allowing weaker signals to be received.  A preamp normally is not needed if your antenna feed has low loss.  If you cannot use premium quality coax or if your coax is over 50 ft., this preamp installed at the antenna should improve reception.

Read all about it.

LNK-137 Preamp .......$89

(Ship wt. 1 lb.)

For installations where interference is caused by nearby transmitters, such as near an airport, this low-noise preamp with a 3-section high-Q filter may solve the problem. It is installed in line with the coax from the antenna.

Maximum 40 dB rejection is obtained for signals more than 7 MHz above or below the 137 MHz band; however, some benefit is achieved even for signals closer in frequency.

Read all about it.

LNP-137 Preselector ......$89

A5 RCA plugs for above. A special rf type plug with cable clamp...$0.75/each

Here is a high quality, omnidirectional antenna for use with the R139 Receiver. It is optimized for satellite reception with true circular polarization to capture the most signal throughout the pass.

The APT-2CP turnstile antenna is probably the most commonly used antenna to receive APT signals from the polar orbiting satellites.  It is omnidirectional and therefore needs no tracking system.  

High quality images usually are obtained once the satellite is above 20 degrees in elevation -- providing approximate 140 degree beamwidth.   Unlike horizontal antennas, you will get good reception when the satellite is overhead, and good low angle pick up.

The APT-2CP is really built tough! The mast is 1in. o.d. x 3 ft long. The elements are 3/8 in. solid aluminum, and the hardware is stainless steel. The 50 ohm feed uses a UHF connector. The antenna is mounted to your tower or mast with two stainless steel clamps.

Dimensions of the antenna are approx 36" high (above mtg bracket where attached on your mast) and 42" square max horizontal dimension.  Carton is 7 x 3 x 44 inches.  Shipping weight 6 lb.

Click here for more information.

APT-2CP Antenna $155.00

Ship wt. 7 lb.
s/h $17 east of Miss. River
$21 west of Miss. River
$40 anywhere outside 48 states

APT-2CPx Antenna for use in countries without access to US standard hardware and tools $160.00

Note: Assembly of regular model requires 7/64" and 3/32" allen wrenches and 5/16" nut driver.  Export model includes spare hardware in case lost and tools.  Order APT-CPx model if you don't have access to U.S. std hardware and tools.

I purchased your APT-2CP turnstile antenna and it works great with crystal clear reception.  I am in Hattiesburg, Mississippi, and we took the direct hit with Hurricane Katrina. The antenna made it through the storm without any damage.  We had 12 hours of hurricane force winds and I recorded on my own gear 138mph sustained. The 10 foot pole which the antenna was on has a slight bend. That will give you an idea of the force of the winds. The house I was in barely survived but the neighborhood was demolished from wind and downed trees. I just thought you might like to know just how good that antenna is!...Bob Pullman; Petal, MS

Thought you would like another testimonial about the R139.  The R139 is the best WEFAX Receiver for the money on the market today!  It' simple but robust design has given me years of pleasure.  I run the APT-2CP mounted at 25ft  with WXTOIMG software. The pictures are just amazing!  Thanks for a GREAT product!...Tim, N8DUY

II have installed your 137MHz preamp and preselector onto our NOAA APT receiver at http://www.phys.unsw.edu.au/~map/weather/ and I'm pleased to report that the picture quality has improved from generally reasonable... to generally excellent! Good gear mate. So good in fact, that my boss wants me to install another set permanently onto this receiver (I will be shipping the present preamp + preselector to Thailand shortly).  In addition, a friend of mine would like an additional preselector, and I'll also grab one for myself.   ...Andre, New South Wales

I recently purchased the R139 Satellite receiver and ATP-2CP Turnstile Antenna.  very impressive.  I set up the system in my truck and went to a beach near my home on Cape Cod.  the attached pic is the result.  keep up the good work! ...Jim KC1KM Harwichport, MA

Just bought a R139 from you last week. I couldn't be more pleased with the quality and sensitivity of the radio. I ordered it Tuesday and received it Thursday. Horizon to horizon noise free pics with no preamp and my 2 meter cross yagi. ...Mike Penkas, WA8EBM

Thanks very much for the speedy service. I tried out the receiver yesterday with a 2M Yagi. Wow! The improvement over my Radio Shack scanner was amazing. Great image of hurricane Alex out in the Atlantic. Thanks again for an excellent product at a fair price. ... Bob Sandness; King City, Ontario, Canada

Just to let you know that my rcvr arrived Monday, and I have been having a blast with it ever since. It works fine and I am getting some pretty awesome images with it.  Thanks!  ...Les Vaughn; McLeansboro, IL

I recently ordered one of your R139 receiver kits.  It was very easy to assemble (a six year old boy did some of the soldering for me) and didn't take very long to complete.  The satellite pictures I have been receiving are excellent even with an indoor antenna.  The radio is every bit as good (if not better) than the QST reviews.  Thanks for making such a fine kit available.... Jody Savell, WA5NAS

I built the R-139 kit yesterday, and wow...it makes my Icom PCR-1000 look like a toy for this application.  Great S/N ratio and almost noiseless faxes a few degrees above the horizon. Thanks for a well-engineered, nice performing sat receiver.  Sure you can quote me. I'm enthusiastic about the R139. Have been trying to work up the courage to build one for a couple of years now, and glad I finally did. The tune-up instructions were great and everything just fell into place. ...Bill Reid, WA4KBD; Muscle Shoals, AL

The R139 receiver is excellent. I was also surprised at the speed at which you got it to me.  I ordered the receiver wired and tested on Monday, and it was here on Thursday.  I'm getting excellent pictures, even with my 2 meter vertical antenna.  Thanks. ... Clint Parrish, KC9S; Sullivan, IL I connected a simple antenna to Hamtronics R139 for weather image capture.  R139 is wonderful weather fax receiver.  Very, very sensitive reception; no preamp, and no add other equipment.  My location is east Kalimantan.  You can look at the picture with yellow cross.  That is Bontang, Indonesia.  Click photo to see larger image.... Untung Suharto

The R139 Weather Fax Receiver is the Number 1 Receiver that I would recommend to anyone who wants to work with weather satellite imaging.  ..... M. Foster

I was surprised that R139 has great performance.  No Interference from orbcom and good bandwidth !!  I'm satisfied with that performance.  I hope that you keep making a good product.... Kazuhito Jonouchi / JS1BTL

It has been over 10 years since I first set up a low orbit receiving set up. I purchased an LNY-137, LNK-137, and LNP-137 from you folks in the past two weeks. It removed much intermod from satellite receiver IF leakage. There are four such dishes within 30ft of (my antenna). Thought I would never get rid of the noise. The LNP-137 did away with all visible interference and there was a great deal of it to lose. The downloaded pics were trashed with vertical lines. They are no more with the simple addition of the LNP. I cannot recommend this unit too much. The gain of the unit just takes out the intermod and signal loss of the post processing. Very happy camper. Thanks much for everything including the fast order filling and delivery. ... Gerry Rolle

I have your R139 APT receiver which I built from a kit about 2 years ago for my wife, who is a former Air Force meteorologist. It's worked flawlessly, running 24/7 with WxToImg software, registered version.  Antenna is a Woodhouse turnstile 30 feet above a one story roof, fed with 75 feet of RG-8x.   We upload captured images from your receiver here as part of a club effort. Images vary, of course, depending on the angle of the pass.  Many are very impressive. http://www.kb3kai.com/~wa3sws/   Thanks for many years of support, and a super level of usefulness and enjoyment from many of your products.   ... Steve WA3SWS

Just a note of complete satisfaction on the R139 Weather Satellite Receiver. The combination of this receiver and the wxtoimg sound card software, I am getting near HRPT quality pictures. This receiver also outperforms some high ended commercial grade 137 MHz receivers as well.... Jeff, K7XQ; Atwater, CA.

I bought your R139 Sat receiver kit a few weeks ago. Just wanted to let you know that I am very happy with it. I am getting beautiful pictures and having a lot of fun. It is a very educational hobby.... Jim Pesavento, KQ4RI