Author Topic: Matching Pad Calculation 50/75 Ohm  (Read 219 times)

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Offline AllTheGearNoIdea

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Matching Pad Calculation 50/75 Ohm
« on: April 07, 2020, 02:53:26 pm »
Hi I am trying to feed an old domestic radio receiver that has a 75 ohm input. My signal generator is 50 ohms output  so I have built a 75 / 50 ohm matching pad with 9.6db anttenuation factor.

I want to feed the radio with 10uV impt signal at the antenna and I am trying to figure out the signal generator output level. Please could someone familiar with this check my math please.

10uV  = -88.75dBm for a 75 Ohm System (from conversion table)

I have 9.6dB of loss in my matching pad so I set the output of my  50 ohm signal generator  highe to make up for the loss  =   -88.75 + 9.6 = -79dBm

So in theory -79dbm at the output of the 50 ohm signal generator will provide 10uv at the output of the 75 ohm pad into my 75 ohm load

Thanks regards Chris

« Last Edit: April 07, 2020, 03:42:44 pm by AllTheGearNoIdea »
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