Loop Antenna Amplifier service bulletin 2-Attenuator


On 12/14/2019 1:24 PM, Chris Moulding wrote:
Today I built a quick prototype of a dual attenuator box. One side is an 8 dB attenuator, the other side is 20 dB.

I've attached a photo to help explain the 8 dB tee attenuator I described yesterday.

With this simple layout it has good VSWR up to 250 MHz and with correct internal shielding added could go much higher.


How much higher freq/lower SWR could you get by connecting each "T" to the adjacent BNC jacks on one side of the box, instead of spanning the full width?  

Stephen H. Smith    wa8lmf (at)
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Chris Moulding

That's a very good point. I'll try that tomorrow.



Chris Moulding

With the revised layout it has good VSWR up to 1300 MHz (the limit of my HP network analyser).