Alas, my petulant neuroticism was tugging at my sanity until you stopped to add that second zip-tie; I sincerely appreciate the accorded strain relief!
Lots of good info here and presented very well. I built a low voltage (18-80vdc) multiplier off the Lionel Z Transformer. Very handy. This one will compliment mine, I will add a voltage divider to get an assorted range. Thank you.
I am not from the U.S. but here we need to connect all metal parts from mains powered piece of equipment to earth, unless double insulated. I know that the original design is from 1959 but earthing the metal housing would add an extra level of safety.
Thank you very much. I love projects like this AND I needed a cap tester for a job...so again, THANKS! In addition to the crafting of the tester, this video is filled with all kinds of time saving tips and useful shortcuts everyone should benefit from.
To improve the isolation from the mains might I suggest you put two small low power transformers of value 240:12vac with the 12Vac secondaries connected together. The mains will step down and then step up again. This is a lot safer than relying on the 100k resistors to not fail and then electrocute you at the capacitor terminals or from capacitor test terminals to any earth in the lab. If you want to limit the maximum power output you could also add a 100 ohm resistor between the 12vac transformer secondaries. The maximum power available is then 1.44watts / 2 from the step up transformer.
Hi Ian. I do not want to be rude, but you should have a look at Mr Carlsons capacitor tester. It is a better, modern tester, and it does *not* use high voltage. Stay safe
I’ve seen it and I believe the fact that it doesn’t use high voltage to be a fundamental flaw in his design. I’ve found caps that didn’t show leakage until several hundred volts were across them.
@@nonn4562 they both have their place and if you listen to Mr. Carlson I think he believes the same thing. He’s not giving up his high voltage testers anytime soon. Especially for checking old wax caps and such such as in this video. The design might not be “free“ but for two dollars a month you can have access to his Patreon and if you’re really on a tight budget you can cancel it after a month. So everything will cost you two dollars. I was a member for a few years and constantly got value out of that two dollars. I canceled all of my Patreon subscriptions last year because of financial issues. But will be rejoining his Patreon ASAP. That $2 will give you a month which is plenty of time to print everything out, order all the parts, ask any questions, and have access to his forum community. I’m really big into test equipment, half my business is woodworking but the other half is spent in my lab repairing industrial electronics and test equipment. 80% is component level board repair with a bit of metrology sprinkled in For “Fun”. I found his designs and information on Patreon infinitely useful for my business. And my hobby of repairing and recalibrating high-end test gear. I can honestly say that two dollars a month is a bargain for his Patreon perks. You have access to endless amounts of information in his community tab/forum… And you have access to dozens of designs regarding test equipment. Everything from the DIY curve tracer, protection circuits for your oscilloscope and input, isolated probes, The Carlson “super sniffer“, and so much more. And most importantly you get to see how hundreds of his projects that have been built by other patron members and see their documented process and build notes. Seriously? Two freaking dollars? It really is worth two dollars a month and the money goes to someone who has brought more to the electronics RU-vid community than anyone else. I know he might not have the most energy or brightest personality or crazy antics of the electronic channels on RU-vid… But I trust him more than I do anyone else when it comes to complex electron theory. And working on things without getting killed.
@@iainportalupi I have thought long and hard about Paul's low voltage capacitor tester and thought that the low voltage aspect of the tester would be no good since capacitors begin to fail at the high voltage end first but I have seen him use it and compare it against the high voltage testers and there are some capacitors that the high voltage testers didn't pick up on that the low voltage did! There's something about the way that his tester works that we don't really understand! I ended up using a DC to DC converter to step up the voltage which also gave me adjustable output voltage and I used an analogue current meter to show the amount of leakage. This worked well but I was still working with a home made high voltage device. Everything changed when I saw a how to use a perticular LCR Bridge Meter on XRayTonyB's channel, I had been watching that device on eBay for years but it looked complicated to use so I held off getting it. But after seeing that video, I purchased it immediately and have never looked back! I got the new version which has a built-in lithium ion battery and is charged via USB C! It's quick and easy, on the one screen I see capacity, ESR, leakage (or drain), quality and phase angle! It's low voltage but it works! I have compared it to my home made contraption and it checks out perfectly. It cost me $95Au which should be cheaper in the US (the Australian dollar ain't worth the plastic it's printed on LoL)... I highly recommend it for anyone who has a budget that can stretch that far... Your device is the first one that I have seen to actually work for little financial outlay... If I would have done anything different, I would have put in a shunt and a uA analogue meter to show the amount of leakage! The neon works but for me it's like the led level meter on Paul Carlson's tester, it's doing something but what exactly?
Hi Ian, great video, since this is a project you modified from an electronics magazine article way back in 1959. Should you not recommend that people who build it should use an isolation transformer, as we are using high voltages. I notice you mention high voltage, and safety. But should you not highlight the need for the use of an isolation transformer? Al.
This was a great tutorial - but the best tip I got from it was to draw a ruler on my work bench! Again - FREAKING BRILLIANT!!!!! Something I've been looking at is trying to build a capacitor foil end tester. Do you have an opinion on whether this is really worth the effort or have you built one yourself? If yes, I think your style is instruction for this would make a GREAT video. Thanks again for sharing.
Thanks, the ruler is super useful. As far as the outside foil detector… Finding the outside foil on a cap is one of those things that makes a difference in theory but in the real world makes no difference. I say this for three reasons. 1) look at all the exposed, non-shielded wires and resistors running everywhere in tube gear. With all those exposed going everywhere using the outside foil to shield a 1/2” of a capacitor isn’t going to make a bit of difference. 2) the biggest source of hum in AA5 radios are from the less than ideal power supply designs they used in order to cut cost and parts. 3) I’ve restored a bunch of radios with factory installed caps that were installed with no regards to the foil orientation. My radio repair manuals from the 1950’s never mention foil orientation either which makes me think it wasn’t on their radar. It certainly doesn’t hurt anything to figure out the outside foil end and install it towards the low impedance side of the circuit but as far as I can tell the only person who really cares about it also happens to be the person who provides plans for the tester on his patreon.
Watched the entire video. Interesting stuff. I understand this is for testing leakage of high voltage capacitors. I got a 40 year old analog drum mashine and found 96.8% of the capacitors to recap it. Two of the caps (0.47uf & 2.2uf) 16v capacitors are a thing of the past...I can't find them. This is not the device I need to test them is it? lol. I can replace them with 50v variety but they are for audio signal generation and I'm concerned about how capacitors with 3x the voltage rating will shape the audio signal. How do I test those little old capacitors? TIA.
Why would you put a 120v/336v project in a metal box with a two-wire mains cord and not have a three-wire cord with the box grounded in a head-scratcher..
so we meet again! clearly you have been busy! however, i need to check the capacitors while in circuit. also cant a voltmeter do this? the computer industry has died! and i am now buying used equipment! my life has become "reached!" the new motherboards have a light on them when you turn them on, when turned off they go out in 3 seconds. on used boards it takes 3 minutes! i suspect it is old capacitors but these are solid not electrolyte and im curious if they should be replaced. also "RADIOS?" how old are you? im from the days of nixon.
charles klein for motherboards or any of that modern space age stuff you really want an equivalent series resistance (esr) meter. The esr of electrolytic caps increases over time until the circuit it is in no longer functions. This is what kills off many flat screen TVs. The beauty of an esr meter is it can test the caps in circuit. As for how old I am I was told by the guy at the plumbing store that I was 100 because I went in there looking for a spool of lamp wick to seal some iron pipe joints.
@@iainportalupi SO YOU "FART" DUST! i know about esr and have spent alot of time looking for one! lots of luck! they also have meters that check "chips!" and if you believe that one i have an edsel you can buy! actually edsel was a good car depending on the engine. you could get a straight six 300. you have a "plumbing" store? WOW! what about MALT shops? its been several decades since i had a malted! and "FOX" theaters! is "beaver" alive their? YA! you been doing LSD! "Alice" dont live their any more!
Two towns over had a malt shop until last year when a pipe burst and flooded the place. I used to go there quite a bit. We have a Paramount theater in the city next to me.
@@iainportalupi I beg to differ, a capacitor with high ESR has never destroyed anything! Sure! They might not filter the power supply section properly but that's about it! The capacitors that are responsible for stopping equipment from working are the ones which leak DC! I have found plenty capacitors that have shown very low ESR but leaked like a sieve! Unfortunately there's no easy way to test capacitors, they always have to be removed from circuit! I find it frustrating when I watched someone test capacitors in circuit with an ESR meter and claim that all the capacitors are fine! There's just no easy way around it! The only thing that you can do is make sure that when you replace capacitors, always go up in voltage wherever possible! Since they fail from top down, a much higher voltage rating capacitor will take longer to read a failure point where things stop working...
Yeah, they shure did things different way back when. That is for a good (safety) reasons. I think this is not a good project for beginners. This thing will kill. And why putting it in a metal, not earthed enclosure?
@@iainportalupi because its non isolated , voltage not adjustable &does not allow accurate reading .you can find better yet as simple circuit diagrams online using fets & opamps as tran impedance amplifier to read the leakage current . Good luck
