I always love your repair videos, they are some of my favorite videos on youtube; the production quality is great, and the methodology used is consistent, logical and often surprisingly understandable. I always learn something when I watch your videos and I just want to thank you for that.
My better half is always chiding me about having so many varied components on hand but sure pays off on a Sunday afternoon when you're deep into something and need a part! But I just checked my zener box and of 15 different values there were no 4.7V's there; must be a rare one! Great repair as usual and a wonderful way to pass the time while snowed in with the East Coast of the U.S. in the midst of a huge storm.
Again thumbs up, I enjoy your repair videos, its possible to learn a lot and see how you track down the faults. Absolute great!!! And your video quality is one of the best, not moving to much and most of the time showing the relevant picture. I am waiting for the next :)
This is a good illustration of repair techniques: qather data, carry out inspection, propose a fault scenario, etc. One point though, if a diode is shorted you do not have to check it in both directions. A shorted diode is no longer a diode.
Keep the repair videos coming. Cant believe that people thumb down your videos.. I am going to go through all the ones i watched and make sure that they are thumbed up! :)
Nice work! But especially thank you for uploading the manuals as these are really good for learning and building your own LCR meter. To bad that those really educative and detailed manuals are getting so rare on modern test equipment. Well, at least on affordable equipment :)
Great video as usual. I really enjoy your repair videos. Being a newbie at electronics it's great to see the approach to finding the faults of the unit. Keep the videos coming!
Shahriar on fire, love new timeframe for SP videos :) Cat's approved! +1 for schematics, would be happy to add into collection, with PM6304 one I already have, which is bit different.
Envious that you seem always to find failed gear that is (relatively) easy to diagnose and repair ... no obsolete parts, custom-made ICs, bad firmware, parts that have only OEM part numbers and no common part numbers (e.g. vintage HP). Nice job tho and I learn much from your videos.
Poor Zeners. They always have to take one for the team! Do they always fail short circuit? I guess they have to to do their "protective" work, but is that a given? But they really work. I stupidly connected a harddisk I got to "save" data from (it hung quite often, while making a clicking sound) with 5 and 12V switched around (I swapped the pins on a connector so I could run fans on 5V instead of 12, but forgotten that that one line was "fan only" after 5 years). The HD controller board sizzled while a Zener acted as crowbar and two small inductors (guessing, they weren't there anymore ;) ) acted as fuses (and burned a hole into the PCB). The same way as here, I followed the traces and checked which parts could have been damaged. After removing the charred hole and filling it with superglue, I bridged the inductors and removed the Zener. I managed to get all data from the disk. In the end it had around 100 unrepairable blocks (down from a thousand, but the recovery program managed to get most of them after many tries). Pretty sure the bad blocks were there even before my stupidity. Even though I didn't know where the bad blocks were, I made an image to a new HD, which is running fine now (so looks like it didn't hit any important OS files, if the bad blocks were in files at all).
I used one to test 4k of capacitors that had been in storage for 3 decades. 99% plus passed perfectly, pretty good for the 10uF 25V wet tantalum slugs. Many were detected as pure capacitors as well, leakage below the instrument measuring range ( or below the detector noise floor), and I did do a before and after test on some after 24 hours of bias with no difference. The unit was the Phillips version, in the brown and black case, but otherwise identical. Saved myself a lot of heartache in testing components that were NOS before installing DOA ones. Plus was good to use as a transformer tester as well to find shorted turns, using a known good one to get the values.
Great video! If you have some time, could you create a short video of how to properly make the 4 wire leads with the kelvin clips? I always think it would be nice to make my own leads, but I am worried I will introduce errors in my measurements if I mess something up. Thank you for all the hard work you put on this videos!
Salam Shahriar, I bought 5 APC RS-800 UPS's for $25 knowing they don't work properly, and plan to repair them for my lab. I found the schematic online by googling it, and was wondering if you would be interested in doing a video on how they work and how to fix them. I've never worked on uninterruptible power supplies, and am too lazy to spend hours analyzing the schematic to find out how this one works. Looking at another make and model, I noticed that share pretty much everything. I Found your excellent channel when I sub'd to Peter Oak's channel. It was an excellent find. Excellent work. Merci O, khodafez :)
Another great video, you have a real gift for explaining technical subjects, and I have to guess you owe this to your parents or teachers earlier in life, someone certainly taught you how to make a point succinctly, yet interestingly and with sufficient information therein :) I have one of these testers, badged as a Philpips,, and although I haven't broken it yet it was fascinating to get a clear insight into how it works. I once asked Fluke for a price for the little component testing clip that will plug into the banana sockets and allow testing leaded components without the test leads. The price was simply ludicrous, but they insisted it was correct... If you have the time and inclination I would like to know more about how you might perhaps do the maths or whatever to convert inductive measurements at 1khz into what they might be at higher or lower frequencies. Many thanks, I am always in happy anticipation of your next video!
4 yrs late, I clicked purely because I fully expected to see the cat jump into the chassis as soon as he took the lid off. I wonder if he still has Signal Kitty?
The layout of the of main board seems a little low density. I am surprised that they do not may this instrument half width. Additionally I am impressed with how simple the instruments is.
Love the repair videos!!! The cat is cute but that would drive me nuts cause they cant stay on the ground! Its cute though =) Guess I'm just a dog person. Keep the repair video coming and I don't mind the cat, kinda like your helper.. =)
+Aurelius R The 'checking the supply' clip, and the one before it both segue into checking the schematic. I think he spliced them together in the best way possible.
Hi, thanks for sharing. I like your repair videos very much. I was wondering what kind of wires/cables you used along with the 4 wire Kelvin clips. Cheers.
this pcb is clearly from 80's. all the routing is look like handmade without computer. probably with stickers. we called them letraset. which is actually name of the company produces that stickers for electronic design. also i beleive there is a solder under the green mask which is also very common in through hole plated pcbs in 80's.
Awesome video, thanks i learnt a lot. Could you advise what a fair price would be for a Fluke PM 6304 LCR meter? Would it be possible to get the circuit diagrams for the 6304 should it go faulty?
I wonder, it seems like a really obvious potential user error to hook it up to a component that was still charged, so is there no other way they could protect the components or provide some kind of safe discharge path? As you said, the zeners seem to have part of that job, protecting most of the rest of the components, but blowing half a dozen components all across the front-end seems pretty catastrophic. Or would it be that any component that could protect the circuit more, would interfere with the ability of the circuit to perform the measurements it is supposed to?
+Daniel G Some LCR meters first detect the presence of voltage and provide a dedicated discharge path. Of course this makes the front-end more complicated.
+DerAlbi You are correct. The instrument shows the reverse behavior. This is because it was put into the parallel L/R mode with a dominant component pointing to R (by mistake). I have added a note to the video as well. Thanks!
+The Signal Path Blog Thx, of course the formulas change then :-) Nice trap. I was first thinkng that the ferrite core would cause eddy currents so it would decrease inductance when its deep inside the coil. However this method of tuning wouldnt make sense for LC-based receivers (which i supose the inductor is made for) due to bad Q. thx for the video and response :-) aaand for the cat. i need more cat in your videos. awwwww
