DEVMO 8-32V to 45-390V DC-DC High Voltage Boost Converter ZVS Step-up Booster Module

Though this power supply says it is 45-390 Volts, it actually delivers two equal outputs: +45 to +390VDC and -45 to -390VDC at the same time, a max differential of 780 volts. The two outputs track, more or less. A precision 25-turn pot sets the output voltage. Output is not floated, but is tied to the common input ground. The two 10-uF aluminum electrolytic caps on the two outputs are rated 400V, so it is probably best to operate this thing at 300V or less. If you are using only the positive (+) output, it might be a good idea to lightly load the minus (-) output to keep it from floating up too high and popping the cap on the negative rail - may be unnecessary - just good HV practice. The unit does have bleeder resistors on the output, so that when you turn it off, the output voltages drain off within 10 seconds or so to safe levels. This is a regulated switching power supply. Output voltage does not track input voltage, but rather is independent of input voltage so long as supply voltage is sufficient. One reviewer stated that he wanted high voltage and 700 mA for plating; assuming 300 VDC or so, that would be 210 watts, well above the rated and fairly respectable 40W. Another (3-star) stated that it took him a while to figure out that output voltage is adjusted by a tiny screw. Please, people. This product is for folks who have a basic familiarity with electronics or aren't afraid to do a little googling to figure out what they may not know. Yes, documentation could be a little better, but then they'd have to charge more. The trimpot on this unit is a look-alike of the 25-turn Bourns unit; just the trimpot here in the US runs $14.66. Go figure. I recommend this unit, plan to use it to supply +200V to power an old 6E5 fluorescent "tuning eye," bought on eBay, if you remember those from old AM radios. I think it will do just fine. Just don't lick the output when it's set to 300V to test if it's on. Ouch! Use a voltmeter instead. If you don't have a voltmeter, buy a voltmeter first. If you aren't sure what a volt is, maybe you should start with lower voltages. 1.5 volts, for instance. Buy a AA battery and measure that. Electricity and electronics isn't that hard. But learn a little before you start fiddling with hundreds of volts. Learn, live long and prosper. In that order.

Works well with good regulation at 250v under 100mA. The transformer gets hot after 30 minutes. See the gm measurement for a 6L6 below

I'm not sure if this is standard but my board has an extra capacitor and output for a negative rail! I measured a maximum 815VDC between them! That's a lot of voltage from such a tiny package :)

No documentation, but doing a search for YH11068A turned up some info, including a reverse-engineered schematic diagram, and some noise analysis. As delivered, this is configured to operate on 10-32vdc. To reconfigure for 8-16v, a soldered jumper evidently must be moved, but there is no clear indication of what to move, and everything is surface-mounted. Continuous output power is said to be 40W, with up to 70W peak. Output voltages, both positive and negative, are independent of input voltage, and set via a 10-turn pot. This operates at 75kHz, and uses half-wave rectifiers, so don’t expect it to be especially quiet, electrically. It’s good enough for what I need.

DEVMO 2 Pcs 8-32V to 45-390V DC-DC High Voltage Boost Converter ZVS Step-up Booster Module $28.98. Some schematics and documentation would help this product a lot. Before connecting it, I always inspect the PCB. The soldering was done by some kind of chimpanzee. There were solder bridges and several not soldered points that were not making a connection. Some cleanup of the board was done before applying power. There are pins for a fan, so if you don't add a fan, keep the power down low as the spec assumes a fan on the MOSFET heatsink. Forget it. I set it up on the test bench. 10 volts in for 153 volts out. Looks OK. While starting to write the review, it stopped working. No smoke. No reason apparent. Nothing moved. Just hooked to a power supply and a voltmeter. If I really needed this right now, I might do some debugging. I would say, don't bother.