Of course. If your preamp has a D.C. Blocking capacitor at the output, you can usually extract the D.C. by simply putting a small RF choke on the output pin. You MUST have a blocking cap. Generally, for narrow band use, it's not fussy. ARR suggested a 1 mH RFC. Try it. Bias T's get fancy only if you want broad frequency coverage.

Ed Krome K9EK Sent from my iPhone

On Nov 26, 2017, at 3:02 PM, Scott scott23192@gmail.com wrote:

Hi everyone.

The schematic makes me think "yes", but I wanted to check before making a purchase.

Normally a bias-tee is used to inject a DC voltage onto your coax to power a pre-amp. Since some pre-amps aren't powered off the coax, but rather from a separate pair of pins, I was wondering if you can use a bias-tee AT THE PRE-AMP to extract the DC voltage off our coax for connection to those external power pins on the pre-amp?

Running a separate cable to power the pre-amp is not the end of the world, but it would be convenient if I could turn on the bias voltage available on the Airspy or RTL-SDR and then extract it up at the antenna to power a pre-amp.

Thanks for any recommendations!

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