ugliest power supply

There's far worse out there. It's cheap anyway.

NT

I have some Amazon reward points kicking around, might be interesting to do a teardown!

Unfortunately I have two other "Amazon special" power supplies sitting in a closet non-functional. One of them looks nice on the outside, but has the grossest through-hole soldering job I've ever seen. It looks like someone used a pipe iron to drip the solder on the pads.

This is actually a really nice "Amazon Special" linear bench power supply:

Most of the halfway decent ones are made by one of a few Chinese outfits, at least one of which private labels for B&K.

I like my Rigol triple supply, but it wasn't all that cheap.

--sp

There are a zillion clones of that one. Mine is branded HYElec. Has some interesting modes like latching up if you cycle the power with voltage still on the output. Current limit doesn't work till you cycle power with it disconnected. Can't use it for current limited battery charging.

Looks like it might have a hidden feature. The left end of the LED display has a vertical 8 segment bar graph designated "RF" screened onto the front panel. Is there an internal RF generator inside? Or, is the power supply sensitive to RF and the bar graph indicates how badly the circuitry rectifies the RF?

Anyone recognize the vendor mark on the 2n3773 bipolar transistor case?

RL

Seems to be a crude RF signal level meter (for repairing cell phones I guess the antenna is behind the crystal. A few tens of mW

I don't understand the label that's on the top-- it says something like (based on a video of a similar unit):

Phone and power spacing and indicate strength of nexus (reference value)

The Amazon reviews are.. amusing.

--sp

Some Chinese outfit. Should be

Interesting, I don't recall noticing any problems with this one. Can you detail exactly what settings you used so I can try to reproduce?

That one is available at Amazon-India for a mere US$525 at today's exchange rate :-(

This is the one I have:

It has an LXI interface so you can talk to it over Ethernet.

On the plus side (ha) you can finance it at only 3100 INR/month 13% interest (US$46).

Probably not exactly selling like hotcakes (or samosas).

--sp

discarded wallwarts are cheap.

NT

which raises the cost even further.

NT

Turn it on. Connect it to a rechargeable battery. Voltage doesn't seem to matter. Set the current limit where you want it. Cycle power. The current meter says it's no longer limiting current to the value you set. Don't recall the exact number.

I was afraid to leave it in that mode long enough to diagnose it. I really didn't need it...garage sale impulse purchase. I just put it in the attic. Somebody who comes to my estate sale gets to fix it.

Mine's a pretty old model HY3005D, so the problem may have been fixed in a newer clone.

Wonder if Hakko is gonna sue for using their trademarked colors.

Tim

-- Seven Transistor Labs, LLC Electrical Engineering Consultation and Contract Design Website:

I've always wanted to get into the export business!