An ice fishing box to house my ic-7000, an atu, a battery pack. Very crude but solid rack made of pine board I had laying around. This is cobbling of the best sort.

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1 point

How much power does such a radio need? At what voltage (or just I and U)?

Ever since USB-C powerbanks with up to 20 V from PD are a thing, I use them for as much as possible.

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2 points

Voltage is generally standardised to 13.8 V (don’t ask me why).

I don’t know what exact radio that is, but it looks like it can probably transmit at 50 W.

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6 points
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13.8v is the charging voltage of lead acid batteries. So it stuck.

That’s a ic-7000 and it does 100w out on hf.

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2 points

It looks like for FM it can go up to 100w.

https://www.dxengineering.com/parts/ico-ic-7000

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0 points

Ah makes sense: alternator voltage of a car. I assume it works essentially just as well on 12 V, but USB PD, as of today, can not do 100 W or ~9 A at 12 V.

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1 point

Amateur radios are generally spec’d at 13.8v plus or minus either 10% or 15% so that they work on a non-running car (12.something volts) or if an alternator is running a bit hot. A 100W radio like this is pretty much always going to require around 20amps at full power -but they have adjustable transmit power. They don’t transmit as well at the lower voltage range, but most people don’t worry about it.

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1 point

How much RFI do those power banks spew out?

USB PD only goes up to 3A at 15V. That’s not enough current to run a mobile radio.
A small LiFePO4 battery is a much better choice as it will supply a stable 12.8V without any switch mode supplies.

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1 point

@AG7LR
@Eheran This is incorrect. USB PD does 20V 5A (100W) with the common 3.0 version. 3.1 increases that to 240W using higher voltages. https://www.usb.org/usb-charger-pd

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1 point

Most radios won’t run on 20V or higher. At 15V or lower, USB PD is limited to 3A.

If you wanted to get 100 watts, you would need a buck converter to step 20V down to 13.8V. Now you have two switch mode power supplies producing RFI.

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1 point

I agree. Never measured the RFI since it usually replaces a cheap switchmode power supply from mains, so can only get better.

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