APT-06 / APT-06AD

Dedicated Weather Satellite Receiver
Small, reliable, professional quality and performance...

Automatic Operation

The APT-06 was especially designed to receive Polar Orbiting Weather Satellites in the VHF frequency range. It feeds the received image data into the sound input of a computer for further processing so that an automatically operating weather satellite image reception station can be set up.

American polar orbiting NOAA-satellites continuously deliver very sharp weather images all over the world. Real-time images from several active satellites can be acquired about every 3 to 12 hours. Satellite sensors deliver visible light as well as infrared images. Therefore even nighttime satellite-passes deliver full-scale cloud- and temperature information. Software options allow automatic creation of time lapse loop animations of NOAA satellite images.

View a sample animation
Front view of the APT-06 weather satellite receiver
  • USB powered, no external power supply needed
  • Direct computer control via USB
  • High noise immunity, strong filtering
  • Automatic, unattended image-recording for later viewing
  • Built-in speaker
  • Model APT-06AD with antenna diversity

Great Performance

An exactly matched receiver IF bandwidth of ±16 kHz together with an extremely linear phase-locked-loop-demodulator guarantees the superior image quality and precise temperature calibration WRAASE / WeSaCom Systems are well known for.

Satellite frequency Doppler shift is precisely compensated by a special AFC-circuit, which is fully active already when the satellite comes up over the horizon. This eliminates noisy reception periods when the satellite is quickly approaching from long distance.

In addition, an active filter circuit carefully matched to the satellite subcarrier frequency is implemented to reduce remaining noise components. In the input RF amplifier, high-quality high-Q-filters with silver plated and shielded helical coils provide a very high immunity against interference from strong signals in the close-by aviation and ham radio bands.


Small Size

The APT-06 measures only 105 mm x 105 mm x 30 mm. Therefore it is an ideal receiver to set up a mobile or portable weather station with a laptop computer, e.g. on board a ship. Due to the rugged, 2 mm thick anodized aluminum case, the APT-06 is a very robust device. When connected to a computer via USB, no external power supply is needed.


Outline-sketch of the APT-06 showing its dimensions. Height: 30 mm. Length: 105 mm. Depth: 105 mm.

Additional Modes

Although the frontpanel button allows manual selection of the frequency channel, the APT-06 will normally run in automatic mode: the WXtoImage software uses its built-in satellite tracking module to control the APT-06 so that the proper channel will be automatically selected for the next satellite to be recorded.

Alternatively the APT-06 can search for active satellites on its own with a built-in scanner. Undisturbed by any other signals it reliably locks only to weather satellites and will not hang on other unwanted signals like simple scanners do. Additional control functions are available with the supplied Windows program APT-Control.


Screenshot of the APT-Control software for Windows

APT-06AD with Antenna Diversity

The advanced model APT-06AD contains an Antenna Diversity Circuit, which under difficult reception conditions provides means to effectively reduce signal drop-outs and noisy image sections by using a second antenna.

The APT-06AD uses the noise value as switching criterion: A fast microprocessor continuously analyzes the signal-to-noise ratio and selects the less noisy antenna. Such antenna diversity based on noise evaluation is much more efficient than simple signal strength based circuits.

Of course, the APT-06AD can also be used with only one antenna with antenna diversity being switched off.


Back panel of the APT-06AD with antenna diversity showing the USB, audio and power plugs as well as two antenna sockets

Technical Data

  • Frequency range: 137-138 MHz (134-141 MHz at reduced performance).
  • Channel step size: 10 kHz.
  • Fixed hardware-channels: 5 (by firmware extendable to 9).
  • Arbitrary channels, set by software: 10.
  • Sensitivity: Better than 0,2 µV @ 20 dB S/N CCITT.
  • Adjustable AF-Output level: 0 to 1000 mVpp (1 kOhm).
  • AFC-pulling range ±10kHz.
  • Low-noise, extremely linear Phase-Locked-Loop Demodulator.
  • Dynamic range 80 dB (at ±16 kHz deviation and 2400 Hz modulation).
  • Channel / mode selection pushbutton.
  • Speaker-ON pushbutton.
  • 5 red LEDs for channel and signal quality indication.
  • 1 green LED, indicates that a satellite signal is available.
  • Antenna input: 50 Ohms, BNC.
  • Dimensions: 105 x 105 x 30 mm / rugged, 2 mm thick anodized aluminum case.
  • USB controlled and powered, no external power required (yet possible).
  • Ext. Power input 9 to 12 V, max. 100 mA, wrong polarity protected.
  • USB Type B socket, compatible with USB 3.0, 2.0 und 1.1.
  • USB cable included.
Additional Features of the APT-06AD:
  • Antenna Diversity
  • Second antenna input: 50 Ohms, BNC
  • 1 green LED indicating the active antenna