A shout-out for Phil at Jumper1 - plus a nice LM317 PSU project - Page 1
Forum section: electronics / projects

author: nzo
author_rank: Regular Contributor
timestamp: August 24, 2011, 11:00:23 pm
content: Phil's electronic projects and presentation are beautifully done with a lot of care. His tutorial videos are excellent. If he finds all is not as it should be at the end of a project, he goes back and fixes it and tells us what he did and shows us how. The world could do with many more like you Phil. Good on you mate!Check out his vids and notes on anLM317 Adjustable Power SupplyJumper1

author: johnboxall
author_rank: Unknown
timestamp: August 25, 2011, 12:22:39 am
content: Fantastic, thanks for that

author: phil_jp1
author_rank: Regular Contributor
timestamp: August 25, 2011, 07:55:20 am
content: Thanks! But my tutorials are far from excellent. There's a lot of room for improvement.- Phil Levchenko

author: patb
author_rank: Regular Contributor
timestamp: August 25, 2011, 08:07:46 am
content: Thanks for the tutorial. Ive just subscribed to Phil's youtube channel. :-) Waiting for the next video.Patryk.

author: shebu18
author_rank: Frequent Contributor
timestamp: August 25, 2011, 08:18:57 am
content: Great tut, i also build these day a LM317 power supply. The other tuts are also great.

author: Zero999
author_rank: Super Contributor
timestamp: August 25, 2011, 01:38:50 pm
content: Hi Phill,Did you try using better resistors for the potential divider? It's possible simply replacing them with 1% metal film would've solved the problem without having to rebuild the PCB.A relay is an interesting solution to the voltage drop problem. Another solution would've been to simply put the switch before the LM317 which will compensate for the voltage drop.

author: phil_jp1
author_rank: Regular Contributor
timestamp: August 25, 2011, 05:30:04 pm
content: Quote from: Hero999 on August 25, 2011, 01:38:50 pmYeah, 1% metal film resistor could've solved the problem, but I wanned to put another output cap anyways, so I've decided to make things right. )Switch before LM317 - in this case it's not an option. Because 1. pretty big output cap won't discharge immediately. 2. output protection diode might be a problem in some cases. Anyways it's better to physically disconnect the load.

author: ciccio
author_rank: Frequent Contributor
timestamp: August 25, 2011, 07:01:18 pm
content: Quote from: phil_jp1 on August 25, 2011, 05:30:04 pmYes, you are correct: the switch must be at the output side...If the load is small, the capacitor could keep the output live for a long time.Keep up with the good work.

author: Zero999
author_rank: Super Contributor
timestamp: August 25, 2011, 07:45:44 pm
content: There is another solution to the problem: an SPDT switch could be used with one set of contacts discharge the capacitor via a resistor when it's in the off position.

author: phil_jp1
author_rank: Regular Contributor
timestamp: August 25, 2011, 10:05:12 pm
content: Quote from: Hero999 on August 25, 2011, 07:45:44 pmBut what if this power supply would be connected to battery or big capacitor bank? That battery or capacitor bank will be discharged through that resistor.Normally it's better to just find an appropriate load switch with small load resistance.