ham radio shack, battery powered

[gabric098]

Hi everyone,
recently I've been exploring the option to power my ham shack (used almost exclusively as receiving station), using battery power.
The reason for going battery is that one of my hobby is to chase NDBs https://en.wikipedia.org/wiki/Non-directional_beacon, those signals are quite faint and it's crucial to reduce the electrical noise to the minimum.

All is super simple when it comes to the appliances powered with 12v. I'll just use a lead battery or if I want to spend some more money, I'll go for a LiFePO one.

The tricky part, at least for me, it's how to power the 5v devices.
In particular: I've got a couple of active antenna amplifiers that are powered via USB cables. I could use 2 cells LiFePO but the voltage would be higher than 5v. I could then add a stepdown voltage regulator (there are many sold on aliexpress), however I'm asking: do these devices add noise to the powerline? I'm trying to use batteries mainly for reducing the noise to the minimum and I would like to avoid to use batteries and then have noise added by the stepdown voltage regulator.

Thanks for your help
Gab

DISCLAIMER: I'm not an electronic expert, my knowledge is limited but I'm trying to improve. Try to explain things in simple terms like you were talking to your 10 years old son. 

[Phil1977]

How much power do the antenna amplifiers need?

To answer your question, yes the step-down-converters can create noise, some of the cheap ones can really be bad.

But you can easily get around it: Use linear voltage regulators for everything below a few watts of power consumption. Just get a heatsink, a 7805 and a 100nF cap. Or buy a linear voltage regulator module, you can also take an adjustable one with the good old LM317T.

Be careful with regulator modules with LED displays, some of the displays are also emitting lots of noise.

As soon as everything is working you can try the step-down-module and see / hear if it makes a difference.

[gabric098]

How much power do the antenna amplifiers need?

Hi Phil1977.
It's rated for 750mA @ 5v

Thank you
Gab

[Phil1977]

That means your linear voltage regulator would need to dissipate up to 5W. Should be absolutely fine if you attach it with an insulator to a small metal housing or to a heatsink that´s better than 10K/W (lower is better).

[gabric098]

Thank you for the reply, I'm working on it.

Now, another, possibly more tricky question: I often use this SDR https://www.sdrplay.com/rspdxr2/. It connects to a laptop via USB cable. Now, would be technically viable to power it via battery and keeping the USB cable just for data?

Thank you!
Gab