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Products => Test Equipment => Topic started by: ko4nrbs on November 12, 2022, 03:00:45 pm

Title: LNA Amplifier gain
Post by: ko4nrbs on November 12, 2022, 03:00:45 pm
If using one of these with a Frequency Counter with a pickup coil how much gain would be needed?  Unfortunately, the gain is not adjustable of these.

(https://i.imgur.com/myOHfVT.jpg)

Bill
Title: Re: LNA Amplifier gain
Post by: _Wim_ on November 12, 2022, 03:26:23 pm
You can put multiple of these in series if gain is not enough. What are you trying to achieve exactly?
Title: Re: LNA Amplifier gain
Post by: ko4nrbs on November 12, 2022, 04:01:26 pm
Quote from: _Wim_ on November 12, 2022, 03:26:23 pm
You can put multiple of these in series if gain is not enough. What are you trying to achieve exactly?
Just want to be able to use a pickup coil on my Frequency Counter to read the frequency of the VFO externally.
Bill
Title: Re: LNA Amplifier gain
Post by: TimFox on November 12, 2022, 05:29:37 pm
Do you have any estimate of how much voltage you will get from your search coil in this application?
(I am sure none of us can estimate that for you.)
If not, try one of these amplifiers and see how much you get from it to continue your design.
Title: Re: LNA Amplifier gain
Post by: ko4nrbs on November 12, 2022, 06:49:48 pm
I may buy a few of them and test to see how much gain I will need.
Thanks,
Bill
Title: Re: LNA Amplifier gain
Post by: ch_scr on November 12, 2022, 08:16:07 pm
About 30dB(+-10dB) should be in the ballpark for a pickup coil? You could also check with a scope (with 50R termination on) how much signal you get "bare", then check the specs of your counter and go from there?