A close look at the MFJ-1708SDR T/R switch

“Want to use your SDR as a panadapter while you’re operating your transceiver? The MFJ-1708SDR lets you do that by connecting the SDR antenna while your transceiver is receiving, and then grounding your SDR antenna while transmitting. I show several tests including actual operation. It’s pretty effective.”

SDR transceivers are great, with colorful waterfall displays that accurately present everything there is to see across the band at a single glance. If you want to know where the activity is, who`s generating splatter, what`s happening in the DX window, how wide your audio is, or what frequencies are clear for calling CQ, it`s all right there!

Unfortunately, it`s information you won`t get from your conventional radio without wasting a lot of time tuning around. Fortunately, you don`t need to get rid of that perfectly good rig to go SDR, thanks to miniature wide-band SDR receivers like SDRplay’s RSP family — now available at a station-accessory price. All it takes is a convenient way to pair one up with your transceiver. That`s where the MFJ-1708SDR comes in. Here`s how it works . . .

Your transceiver and SDR unit share the same high-performance antenna system. This arrangement allows you to simultaneously watch and listen. Then, when you key up to transmit, the MFJ-1708SDR cuts off and grounds the SDR antenna line, providing your SDR with bullet-proof protection from damaging RF. It`s the perfect plug-and-play solution for upgrading your shack to wide-screen living color.

MFJ-1708SDR uses the PTT signal from your rig to initiate the switching, but as a failsafe measure, built-in RF sense circuitry will provide a measure of safety if the PTT connection is lost.

Antenna

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Equipment

RF SHARK SHORTWAVE RECEIVER KIT

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RSA306 USB Spectrum Analyzer

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App - Mobile

My LoTW – Free app for iOS and Android

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Ham GeoTool APP

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VHF

Icom ID-880H

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BTECH UV-5X3 Handheld Tribander

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