AMX PSU

[Tinkerer]

PSU
The power supply is a very important part of the detector.
4 LiPo cells should be sufficient.
If we put the cells in series, this gives us about 16.8V fully charged or about 14V fully discharged.
Or we could use LiFePo cells that are safer, much longer life but less power density.
4 LiFePo cells would be about 14V fully charged and 12.8V fully discharged.

Or should we put the cells in parallel and boost to the higher voltages needed?

Then we need to change these voltages into regulated low noise voltage of several different levels.
It is important to keep the overall efficiency high, to make the batteries last for many hours.

TX:
We need a low voltage like 1 to 3V precisely regulated and very low noise, because the TX noise will transfer to the RX and be amplified.
How much current?
Do we want to run the TX coil with many turns? Then we need only about 250mA current.
Or do we want minimum current with maximum coil turns, then we might need over 1A current.
Then we need a higher voltage to drive the Mosfet gates. 15V maybe?

The digital part:
What do we need?
3V?, 5V?
How much current?

Analog:
We want separate PSU for analog and digital for low noise.
For the amplifiers it is good to have a lot of head room +5/-5V is good for that. We do not need much amps, but we want very low noise.
A switched capacitor converter might be good.
What voltage is the input to ADC? 3V? 5V? we also need that.

Many decisions to be made. Many datasheets to be read.

[Idefix]

PSU has 2 blocks; the supplies and the Batteries is made by the Pomer supplies on board , and the batteries.
As I said in the post Design challenge, , it appears to be interresting to use a commercial Block cell like those used in handtools, like drills.

11 Batteries. Can be specially made, or possible use of power banks , or better: batteries from hand tools - drillers.and so on)

It seems very interesting to use a battery of portable tools, very widely diffused.
The price is very interesting,
it is possible to take more of them with you can change them if necessary in the day.
The charger is also available, and already done.

This is a solution that will not suit a detector manufacturer, of course, but so practical for us amateurs I started a drawing around the PAP 20 battery which is 20V 2Ah, and there is also a 4Ah
The brand I think at is Powerfix, available in Most of the countries in Europe, , available on amazon, too, but more expensive.

https://offers.kd2.org/fr/fr/lidl/pkZFW/

https://grizzlytools.shop/Parkside-2...V-Family-Tools

This concept can be also be adapted to brands available in others countries.

I have made some drawings, not achieved at the moment. I have made trhe first 3D prints to check the fitting.



Then, from 20v, many things are possible.

[kt315]

Two Lipos 18650s, free of money, you can take them from any trash notebook batts. connect STEP UP converter and you get very stabile voltage 12V.
you do NOT need especial board for charge, those "2S 3S 4S', "voltage balansir' board, etc.
buy cheapest charger from ali.

[Idefix]

With 18650 you do not have the availability to change on the field. And the mechanical assembly need to be done, inside your box.

You don't need to buy extra portable drill battery if you don't want. Obviously if you go on field with detector , you are not drilling at the same moment. So the drill battery can be used. In this case it is also for free.

The battery box is already made, is reliable, and generally a power indicator is provided with it.