[ARC5] Chinese 200-350V switching supply errata

[J Mcvey]

I recently posted that the HV secondary ground is isolated from the low voltage input.
If you measure resistance between the HV- and LV- while the device is off, it does measure open.
However, due to the arcane design it appears that a connection is made when it is powered up!
Also the negative side is fused rather than the positive.

I took it apart to modify it for a lower output voltage to power a PRC-10. It looks like one of the transistors is like a pass regulator for the input and the other is the output driver.  I didn't spend a lot of time looking into it, as my mission was decrease the lower end to 135V. I needed to float a ground above battery level negative, so I was able to isolate the buss with a 1n4006. ( supply HV- to anode , cathode to radio ground. ) .


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