TSP  

Nice repair, and good to see a proper cat scan of the burned resistors. My dog (Sophie the "lab" dog) like to steal gloves ;-)

A video with pooch helping is always a great video👍

I think I saw this item on eBay, I could not afford the price though at the time. I want a high voltage power supply for working on vacuum tube circuits. I am planning to build one using similar architecture with toroidal transformer and high voltage N channel MOSFET's. Shahriar I love your style, admire your proficiency, and respect your vast electronics knowledge. Great video again , I look forward to each and every new video.

Your cat can smell the burned components. That explains the interest.

Should definitely test it against an Switched Mode Power Supply and check for the noise in both.

These repair videos are excellent, and the solder work is amazing

That's a very useful power supply for what I like to work on, old valve (tube) gear. Reforming electrolytic capacitors is something it could find an instant use for here. Thanks for showing it.

Being an electronics technician I really appreciate the detail you put into each one of your videos. thank you

Very nice repair job. I love your workmanship.

Total side note: You have a beautiful cat! (interesting video btw)

amazing as always!

Great video.

Great video, thanks!

That’s an awesome supply, I might have to see if I can pick one up too!

Come clean. Pooch is the real brains of this channel.

excellent job. My test power supply is an old Lambda LQD-422. Dual output with dual volts/amps display. All linear of course. About 35 yrs old and works perfectly.

He tried to help you to keep desk clean and organized! ;)

Excellent

Nice job.

I have one. Very precise and useful for my experiments with Nixie tubes. It survived some unintentional abuse, such as a sudden 300V dead short while I was testing some IN-28 lamps. Whoopsie. My only complaint is the user interface. To set a voltage, for example, you have to press "VSET", type the number and then press "Enter". On My Rigol DP821, for comparison, you just type the number and press "V" (for "Volts"), which is enough to let the PSU understand that you want to set a voltage. One less keystroke. It is even more annoying with current limits, since this PSU handles low currents but only accepts values in Amps (or, at least, I've not found a way to specify them in mA), so you have to type cumbersome values like .005. On the Rigol it is as simple as pressing "5" and then "mA". Done. The lack of a rotary knob is also annoying when you want to slowly increase a voltage. You can do it with arrow keys, but it feels more awkward. Just my 0.02€

Very nice repair video, thanks for sharing. You should try a new Keysight handheld DMM and replace the old Fluke. It is so slow !

6:06 33ohm purr transistor... :D

Awwwww look at that cute kitty tail twitching curiously!

Thanks for sharing the video. How about a video on performing curve traces with a PSU and computer via USB. Maybe something like PyPSUTracer on diyaudio.

Fortuitous purchase and repair. I wonder if the power socket was removed to prevent accidental use? A little bit annoying, but your replacement is probably much better than the original socket and I suspect that the wires you used were a touch of overkill as the input power is only in the region of 150 Watts.

It might be interesting to do some characterisation of high voltage capacitors. Their characteristic are quite different to low voltages ones due to different compromises in materials at higher voltages.

With high voltage like that you could have some fun with RF modulation and demodulation using heterodyne tubes, like pentagrid converters or hexodes.

Pooch reminds me of my dog, is too funny. If I drop any paper towels, cotton swabs, etc. the dog snatches it up runs and eats it.

Measuring capacitor leakages at / near their voltage limits would be nice with this. Very swish piece of equipment! Finding out what its output ripple would be under some normal loads would've been nice.

Nice unit, but it seems rather higher voltage than you need for your typical experiments with solid-state and optical communications hardware. Testing of possible protection circuits for front-ends? Exotic microwave electron tubes?

Oh, that's why you are so great at finding problems, you use cat-scan:-)

My cat loves qtips as well...

I am also curious about the addition of the diode. Was there one originally? Was it just a precaution or was it absolutely necessary? (Great video BTW)

Please stress test some X5R or X7R ceramic capacitors, 25V or 50V. I couldn't get high enough for any sort of leakage here.

This was a fun episode. I have no idea what I would do with 600v (other than blow my fingers off)

Are the rectifiers around the 2:50 mark FFUUUULLLLL BRIIIDDGGGEEEE?

it would be of interest what you paid for the broken equipment

Any particular reason "TSP#" designators were dropped from video titles?

Hi Shahriar, at 12:09 in the video the resistors, (current balancing, perhaps degenerative feedback?) you installed are what appear to be 101 or 100 ohms. All of the rest of the parallel devices are using 1000 ohm. Are you sure the replaced resistors are correct? BTW love the cat! All the best.

One of my cats could be Pooch's twin, though without the white patch. He's also intensely interested in whatever I'm working on when I'm at the bench. And one of the other cats also seems strangely drawn by the Q--tips, too. Must be in the DNA in there, somewhere..

I'm a bit disappointed that you didn't measure the output noise, or do a simple transient test...?

10:19 Bottom left a MELF diode bodge with a SMD resistor tacked onto that both flapping in the breeze with no mechanical support to speak of. If they had put a glob of silastic over the components at least it would show they gave a little bit of a crap. It's disappointing to see that from BK more of what I'd expect on a no name supply from China.

That Fluke model is slow, that isnt annoying for you?

How about millimetre wave tubes like a klystron or magnetron video

👍👍

Is there any reason to add the tvs diode? Because your replacement mosfet has already a built in back to back gate-source zener diode. I am asking because I used the same STW15NK90Z on an omron smps where the external 2Sk3875 gate-source diode shorted. I just replaced with stw15nk90z coming with the integrated diode.

If you mistake those two it could be your last one ahahah fantastic

I think you should take a look at modern day high end ATX PSU... Because that 'switching mode Power Supplys have high noise' thought could be broken with that. Modern things are at under 20mV at full load (=650W or so) on the +12V rail and on the +5V and 3,3V rails the best are at around 15mV or under...

My cat also steals Q-tips from my lab table. And bags with little shiny TO-220 heatsinks. No idea why....

Sorry to sound dumb , but a fuse on the line and neutral is bad is it not ? Fused neutrals went out in the uk many many decades ago, at the very least before 1955. I mean if the neutral fuse blows and the line does not you could get a sock if the device is earthed .

Is Pooch a Korat ? (he looks just like my cat!). (I have to put the screws away when I open a device or I latter find I'm short as Eccles has carried one or more off 8-)

Toroid transformers are sexy sexy sexy 😍

Does the USB interface work?

For a guy that can repair a Tek RSA 6114A this was no challenge.

do some microwave/ optical experiment

What happened to pootch the repaircat? In "newer" videos is he missing!

Cat :)

The most interesting I find about this supply, is that they are using MOSFETs that are NOT rated for DC linear operation. That is simply wrong and may have been the cause of the blowup in the first place.

You had to order the resistors? tsk ;)

I always keep my cats away from electronics when I work on them. I am afraid of a static charged cat zapping components.

Q-tip thief haha...

Why does a power supply need an IP address.

Your soldering joints don't look well at all. The surface looks like a cold junction, and has an irregular shape, not sphere-like. Either your soldering iron was not strong enough for the FETs mounted already to the heat sink, or have you used lead free solder? Anyhow, I recommend to redo these. Otherwise, a fine teardown. root cause analysis, and repair.