small power supplies

[rupert kenna]

I want to replace a power supply to a gadget, The gadget requires these inputs:
32 VDC 100mA
7.5 VDC 150mA
4.25 VAC 350mA
Please could you suggest best way to build such a supply both using
... mains 240 VAC input
and/or
... using 5VDC USB ideally with a pass thru battery

 

[AnalogKid]

The 5 V input power option is an expensive problem. That requires a DC-to-AC inverter. Even at a low power level of 1.5 W, that is not a trivial design. Does the AC have to be a sinewave, or can it be a square wave? What does it power?

ak

 

[rupert kenna]

I powers an Oregon Scientific mirror clock MR238. Its old and power supply is damaged.
I think a square wave would be OK. How please?

 

[Harald Kapp]

Oregon Scientific mirror clock MR238

According to the manual I found online that's a weather station, not a clock.
Anyway: From the figures in the manual it looks like the AC adapter has only 2 wires going into the main unit, which means only one voltage. Where do you get the information about 3 different voltages from? That would be a most unusual power supply.
Unfortunately the manual doesn't state the specs of the adapter.

 

[AnalogKid]

The photo shows two wires, but that could be artistic license. The connector has 8 pins.

ak

 

[davenn]

The photo shows two wires, but that could be artistic license. The connector has 8 pins.

ak

I just see a standard fig8 twin pretty common 2 core cable for DC power leads, speaker cables etc


doesn't mean all 8 are there

 

[davenn]

I want to replace a power supply to a gadget, The gadget requires these inputs:
32 VDC 100mA
7.5 VDC 150mA
4.25 VAC 350mA
Please could you suggest best way to build such a supply both using
... mains 240 VAC input
and/or
... using 5VDC USB ideally with a pass thru battery

your unit just shows a single power cable into it

where are you getting all these voltages from ?

please show us a photo of the original plugpack