Bench Power Supply Repair (TTi CPX400A)

Mark repairs a bench power supply that died whilst testing a 5kW amplifier (see previous video, for the demise of the power supply). Luckily, its a well built piece of kit, and not as damaged as feared. However, Mark does get bored of the calibration - especially when it looks too powerful for the other calibration gear!

[VoeViking]

The attention to detail while filming is amazing. I can't imagine how many times you have to move between shots just to show a bolt being unscrewed. Excellent production value, guess you go 110% on everything you do. Congrats.

[Tony-heze]

Hey Mark. I have a B&K 1550 bench supply I suspect got wacked by an inductive load. It's been sitting for years. I almost threw it away because I couldn't find a schematic for it. You inspired me, so today I dug into it and found a shorted FET that switches the output on and off. Replaced it with a similar part I had on hand, and it works perfectly. Love your show. Thank you!

[nickloughrey]

72 year old ex repair guy from the 80, s . Only things I can add are use capton tape around before air gun desoldering and a drop of liquid flux on the pins to help desoldering . What amazes me most is your dogged patience . I would have thrown half the stuff out the window respect !

[audiodiwhy]

I would have been scared to swap the chips as Mark does in the video using just hot air. Very gutsy repair.

[ekus]

Hi Mark, good to see an excellent engineer at work . Just to say that I designed the main power PCBs . The front panel circuit was a successful legacy design and used on many of the other TTi PSUs . I am not on the TTi staff, rather an external designer . The company is very helpful if you ever require schematics etc .

[itsmecenred]

if there were more people like you, the world would be a much better place. While i am interested in what you're doing, who you are as a person is why i keep coming back. All the best from Australia mate

[phoenixdk]

I'd like to speak on behalf of machines and devices, to whom you are a true friend. I tell my electronics bedtime stories about Mark, and his many great deeds.

[qwertyFUBAR]

Sliding it back onto the shelf, and the moment when you push it back and forth a few times just for the joy of hearing the rubber feet squeak... small things like that make life worth living. You are my favorite Internet technician with your deep and useful skill set, the cheerful and dogged determination with which you attack any problem, and your respect for vintage electronics... even a few things we recognized as 'cheaply made' back in the day. You shrug with every new challenge, fix it right, repair the hinges and recast the knobs. You give it your all which exceeds 150%.

[nisiunavoce]

I shudder to think what some of these repairs would cost if fully billed. His shop has just about every piece of electronics kit a tech would want, and that's £££ $$$ alone. Great job Mark.

[stephenmorrissey]

I really believe you'd get 250, 000 subscribers easily if you keep posting. The editing of your videos is probably more of a hassle than fixing the equipment but I really see you getting a significant group of followers. Extra cash flow is always nice as well!
Would like to see you try again fixing that unreleased Bose that stumped you!

[tranquillitydysfunction]

I love that I discovered you due to a companies questionable moral standards. I love your channel and you give me a lift every video I watch

[montygore]

Sir I have been a tech retired worked for 40 years. You are a natural. Very bright and the fastest I have seen at troubleshooting. You are still young I hope you get rich. W5DN

[hydorah]

Well done Mark. Excellent diagnostic skills! Handy to have lab equipment to help you check your lab equipment 🙂

[-Troll-]

I love this guy. His happy face shows how much he loves his job.

[billwoods]

It's amazing to think that Mark's skills include the knowledge to diagnose and repair his own test equipment. Warranties on electronics mean nothing to this guy. :)

[chilledoutpaul]

Hi Mark Just a small gift from one repair guy to another, I only started watching you a couple of weeks ago, Now I watch you all the time! I have a youtube channel but it has remained dormant for ages. Thanks for the great videos & the inspiration.
Paul from Edmonton, UK

[SimonHollandfilms]

Mark....i held my breath....metal screwdriver tip! how about a plastic pot adjuster? great channel

[alienrd]

At 11:36 I shouted at the screen that the chip was round the wrong way, at 11:39 it was correctly orientated, so you heard me then.

[johnlenerd]

This is one of the best things to watch on the telly.

[paulm]

That power supply is actually a really nice piece of equipment; dual 1200 watt channels 60x20…definitely worth the effort to fix that. Nice unit