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SquawkBox Transmitter
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MicroHunt +33 Amp



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   SquawkBox T-hunt Transmitter with voice record/playback : US$ 119

    The SquawkBox T-hunt transmitter provides 50 milliwatts of FM-modulated RF at 146 Mhz, on a board measuring 0.9 x 2.4 inches. Includes a voice record/playback chip with 60-second recording capacity, and an integral electret microphone to record a message.

    Straps selectable repeat times from 15 seconds to 1/2 hour. Standard frequency 146.565 MHz, ( synthesized ) many other frequencies available. ( specify ) Supervised with a PIC microcomputer, 7-15 VDC, 50/5 mA TX/idle.

    Range typically well over 1 mile with a simple dipole antenna. Optional MH+30 1 Watt amplifier. ( see below ) Auxiliary PTT and audio outputs provided to drive an external transmitter. Sold only to licensed amateurs. ( provide your call sign )

  • 50 milliwatts RF at 146 MHz
  • 0.9 x 2.4 inches, SMT technology
  • Voice record/playback chip, 60 second capacity
  • Integral electret mike element
  • Repeat times 15 seconds to 1/2 hour
  • Standard frequency 146.565 MHz
  • Other frequencies available ( specify )
  • Optional MH+30 1 Watt amplifier ( see below )
  • Aux PTT / audio outputs for external TX
  • Assembled and tested : US$119

more SquawkBox info




A & T : US$ 119
   MicroHunt T-hunt Transmitter for ARDF hunts / balloon beacons : US$ 59

    The MicroHunt T-hunt transmitter provides 50 milliwatts of CW/FM-modulated RF at 146 Mhz, on a board measuring 0.9 x 1.2 inches. A PIC micro generates the CW message and ident, at regular ( crystal controlled ) time intervals.

    Intended for international ARDF hunts, where multiple transmitters operate ( sequentially ) on a single channel. Crystal timing is essential to prevent transmission "overlaps", in these hunts.

    The MicroHunt is also often employed as a DF "homing beacon" for free-flight balloons. ( for payload recovery after landing ) Some of these flights have exceeded 100,000 feet of altitude, and yielded signal ranges greater than 400 miles.

    Standard frequency is 146.565 MHz, other ( user-specified ) frequencies available. Ground range is typically well over 1 mile, with a simple dipole antenna. Optional 1 Watt amplifier is available. ( MH+30, described below ) Sold only to licensed hams. ( provide your call sign )

  • 50 milliwatts RF at 146 MHz
  • 0.9 x 1.2 inches, SMT technology
  • Standard frequency 146.565 MHz
  • Non-standard freqs available ( specify )
  • User-defined CW message ( specify )
  • Drives optional MH+30 amplifier ( below )
  • Suitable for ARDF competitions with MH+30
  • Assembled and tested : US$ 59

more MicroHunt info




A & T : US$ 59
   MH+30 1 Watt Amplifier / Modulator : DISCONTINUED ( see MH+33 below )

    The MH+30 is a 1 Watt / 146 MHz amplifier for the MicroHunt / SquawkBox transmitters. A modulator circuit is included for A1 ( CW ) and A2 ( MCW ) modes. When used with a MicroHunt CW transmitter, these modes and the 1 Watt power level yields a transmitter that meets ARDF international hunt requirements.

    The operating mode ( FM, A1 CW or A2 MCW ) is selected with a strap on the MicroHunt transmitter. The MH+30 and MicroHunt TX can be "stacked" atop each other, yielding a very small package.

    One Watt RF output, ( +30 dBm ) with 50 mW drive, at 14 VDC with 200 mA supply current.

  • Amp for MicroHunt / SquawkBox transmitters
  • 1 Watt / 146 MHz amplifier ( +30 dBm )
  • Modulator for A1 / A2 modes. ( CW / MCW AM )
  • 50 mW drive, 12-15 VDC, 200 mA
  • Same footprint as MicroHunt CW TX
  • DISCONTINUED : See MH+33 below
   MH+33 2 Watt Amplifier / Modulator : US$ 59 ( US$ 69 with modulator )

    The MH+33 is a 2 Watt / 146 MHz amplifier for the MicroHunt / SquawkBox transmitters. An optional modulator circuit is available for A1 ( CW ) and A2 ( MCW ) modes. When used with a MicroHunt CW transmitter, these modes and the 2 Watt power level yields a transmitter that meets ARDF international hunt requirements.

    For international modes, ( A1 CW or A2 MCW ) the optional modulator is required, and a strap is required on the MicroHunt transmitter.

    Two Watt RF output, ( +33 dBm ) with 50 mW drive, at 12.5 VDC with 360 mA supply current.

  • Amp for MicroHunt / SquawkBox transmitters
  • 2 Watt / 146 MHz amplifier ( +33 dBm, 10.6 VDC, 320 mA )
  • 3 Watts typical @ 13.8 VDC, 380 mA
  • 0.5 Watt output ( 5.5 VDC, 200 mA )
  • Modulator ( optional ) for A1 / A2 modes. ( CW / MCW AM )
  • 50 mW drive, 5-15 VDC
  • Assembled and tested : US$ 59
  • With modulator : US$ 69

more MH+33 info




MH+33 : A & T : US$ 59
With modulator : A & T : US$ 69
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