[SPAM][CrossCountryWireless] Beverage preamp

Chris Moulding

Hi Steve,

The active device is an Infineon BFR106 transistor.

You will be OK using 75 ohm coax with it without modification. 

What appears to be an output transformer is actually a common mode choke to reduce noise coming down the coax to the amplifier.



Chris Moulding
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On 19 Dec 2022, at 17:48, Steve Bunting M0BPQ <steve@...> wrote:

Hi all

I have a CCW beverage preamp and I suspect I have accidentally put too many volts up the coax from a variable power supply. I was trying to see how much voltage drop there is in my 400m+ long coax run. Looking at the circuit, the only thing that can be broken is the active device. What type is this? I can happily replace it myself. 

I am now using 75R coax. Is it worth rewinding the transformer to match ?