Automatic Transmit Receive Switch

MFJ-1707: Automatic Antenna Switch

MFJ-1707 Automatic antenna switch

Sometimes it is necessary to use separate antennas for receive and transmit. For example you want to use an efficient vertical on 80m for transmit, but a directional beverage antenna for receive. The MFJ-1707 automatic antenna switch serves exactly this purpose. Just connect your transceiver, receive and transmit antenna as well as power - and off you go! The built-in HF sensor (HF vox) immediately switches from receive to transmit antenna. Instead of the HF vox a cable can be used for PTT keying. After releasig the PTT the switch reverts to the receive antenna after an adjustable delay time (hold time). This delay protects for example a very sensitive receive amplifier. An additional switching contact signals the state of the switch, useful for blocking other devices or. The MFJ-1707 automatic antenna switch can be used with any mode. Max. power is 200 W SSB PEP. A 12V DC supply is required, you can use the normal power supply from your transceiver. Size of the switch: 101 × 66 × 38mm.

Order No.
MFJ-1707 Autom. Rx/Tx Antenna Switch 113.00 € Add to shopping cart In stock, shipped in 1 to 2 days.
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TRSWITCH: Automatic Transmit/Receive Switch up to 160MHz


In case you use a scanner or a software defined receiver (SDR) for reception, and you want to transmit with your normal transceiver, you need an antenna switch. Such a device must switch the antenna immediately on transmission.

TRSWITCH does just that. The switch has a connection for the antenna, and two connectors for the receiver and the transmitter. The switching is actuated automatically (RF Vox, from 10mW on) or with a PTT line.

TRSWITCH has an additional AF switch built in: when using an external speaker the receiver is muted, instead the CW sidetone is audible through the speaker. The receiver connector is grounded during treansmission, further it is secured with a lightning protector. Without operating voltage the antenna is always switched to the transmitter (or transceiver).

TRSWITCH wotk from DC to 160MHz, the insertion loss at 160 MHz is 0.2 dB. Max. transmit power is 100W, the device requires 13.8V at 200mA.

  • Impedance: 50 Ω
  • Frequency range: DC - 160MHz
  • Max. TX power: 100W
  • Switching level: <10mW (1.8MHz-30MHz)
  • Turn-on time: <20ms
  • Turn-off delay: <190ms
  • Insertion loss: <0.3 dB @144MHz (0.2 dB typ.)
  • Crosstalk attenuation: > 38 dB @144MHz (40 dB typ.)
  • Power supply: 13.8V DC 200mA

Order No.
TRSWITCH 108.00 € Add to shopping cart In stock, shipped in 1 to 2 days.
Info freight charges
Download: Manual TRSWITCH (PDF, EN, 600KB)