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I have recently gotten a LNA Ebay. It needs 12V 75mA.

Since I want to measure 1kHz to 2MHz I am afraid of noise from a cheap Li-Ion 12V battery/powerbank which maybe has some noisy DC-DC converters. 9V block has insufficient voltage which maybe changes too much when being not full.

So I want to know which battery you recommend principally?

Hansebenger
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    Measure **what**? If for example you want to measure the LNA's gain then noise shouldn't be an issue. If you mean that the **supply ripple** disturbs the measurement, then simply **filter the supply**. How low does the noise and ripple on the supply need to be for a proper measurement? Why not simply use a proper **lab supply**? Anyway: product recommendations are **off topic** here so no one is going to recommend a battery. – Bimpelrekkie May 04 '20 at 19:19
  • I want to measure Electrical fields with an handheld oscilloscope and its probe. I always thought mitigating noise is better than filtering it. I want to build the LNA in a box, so its power supply should be a battery. – Hansebenger May 04 '20 at 19:30
  • You are concerned about the amount of noise from a battery?!? – Aaron May 04 '20 at 19:38
  • The rechargable Li-Ion batteries aren't internally 12V I think, so there has to a DC to DC Converter in a powerbank which is quite noisy? – Hansebenger May 04 '20 at 19:39
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    *I want to measure Electrical fields with an handheld oscilloscope and its probe* My 2 cents: That's not going to work with this LNA because it has a 50 ohm input impedance which will load a (passive) probe so much that you will have virtually no signal left. You **will** get more signal if you just connect the probe directly to the scope. What you need is a **FET probe** type of probe-circuit. A proper FET probe circuit will also consume way less than 75 mA. – Bimpelrekkie May 04 '20 at 20:16
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    You might be able to use this LNA with a **magnetic probe** though, learn here how to build one yourself: https://www.youtube.com/watch?v=2xy3Hm1_ZqI However for the low frequencies you're interested in a magnetic probe might prove useless. That video is from Dave's EEVBLog on Youtube. There are plenty of videos there that you can learn from so that you get a feel for what works and what does not so have a look at other videos as well. – Bimpelrekkie May 04 '20 at 20:22

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