We all love loads ! often not taught or poorly taught but you have put that right !! I would like to see a Load design for sure, and 'space heater' of course !....cheers.
Scullcom electronics did a fully digi/ana load that was quite well done AFAIK. Powered by arduino and some ADC/DACs so "fully programmable" to your heart's content also, with 4 mosfets. Sort of a half-way house between backyard-diy opamp+pot and something commercial.
I saw that. Mine would not be quite so fancy on the digital side though. Maybe a better first project though. Scullcom does some nice stuff but it's fairly advanced.
I don’t know why my comments are not being shown here… nevertheless last trial very interesting video about loads and simple passive loads are still useful and underrated at the same time.
Thanks for your comment. Yeah, I don't know why YT does this. I tried 3 times yesterday to post a reply to a video and just gave up. I know that if there a URLs in a post YT will delete it, but my post did not have any URLs, nor any profanity nor did it contain any sensitive subject matter. YT would just not let me post. I'm glad you finally got through and I appreciate the effort very much.
My eyes must be getting old (or RUclips compression has messed up the colours on the resistor colour codes, which seems less likely). The 6 resistors that make up the sensing resistor on the Simple DC Load don't look like 1.2 ohm resistors, which would give the 0.2 ohm 18W resistor on the circuit diagram. Also, yes a video project building one of these is a great idea. Everyone should have multiple loads in their toolbox, and that one would make an almost ideal beginner project for anyone building up their electronics toolkit.
LOL! Your eyes are not deceiving you! When I drew up the schematic I thought I had a bunch of 1.2 ohm resistors, but it turned out that my memory was not quite right - they were 1.5 ohms, so that should read 0.25 ohms. Good catch.
Oh boy! A lovely load lowdown! One of my favorite uses for my NanoVNA is for characterizing resistors for RF applications. I nearly got a free electronic load from a government lab I worked at. It had a bad meter that was only about $20 to fix, but the group manager said to get rid of it. No other group wanted it and since it was broken they were going to toss it out. At the last minute someone in another group said they'd take it. Now I'm glad they did. It was ridiculously expensive, retail price. It weighed over 200 pounds. It would have been a huge white elephant sitting on casters in the corner of my lab. I don't recall voltage and current load capacities, or even the manufacturer. This was about a decade ago, but it had 8 large high-volume fans and a huge heatsink (probably over 50 pounds of aluminum on it.) I recall the spec sheet had some ridiculous numbers on it. It was all a bit much for testing flashlight batteries in what is now basically a hobbyist lab. :)
@@snakezdewiggle6084 That's a bit of a story. Let me start by first saying, no .. technically, not yet. I have been threatening for a long time, but I live in a pretty sparsely populated area so there are 1) No local examiners so I can take the exam easily. 2) No one to converse with unless I get some pretty decent gear. I did have the exam set up twice in the past but once the examiner cancelled and the other time I cancelled as the roads were closed due to a winter storm. As it is right now the radios I have are CB, FMRS and those I have limited to GMRS frequencies. All of which can be operated in Canada without a license. Since there is a dearth of radio operators in my area I usually just use the GMRS and FMRS radios on wilderness outings (hunting, camping, fishing, etc..) with friends. I may yet try to set up an exam again .. who knows?
@uni-byte You have the knowledge and insight into components and circuits. Well spoken, good pitch. It was a toss up between, school teacher or Amateur radio.☺ It has become an expensive hobby unfortunately. Once you sit and pass the exam, thats your's, for life, like any degree. You can then pay for a license and callsign. I've surrendered my license and callsign since losing my radios, etc. If you know anyone "into" radio, they will your best avenue. Just had a quick peek at your government's page. There is plenty of good info there and links to support. Looks like they have Practice Exams to try out. I think you can sit the exam via video / zoom. That makes it an Open Book exam. When you have some time, just poke around the Gov' pages. Its not everyone's cup o tea.
We all love loads ! often not taught or poorly taught but you have put that right !! I would like to see a Load design for sure, and 'space heater' of course !....cheers.
Thanks Andy!
@@uni-byte :)
Scullcom electronics did a fully digi/ana load that was quite well done AFAIK. Powered by arduino and some ADC/DACs so "fully programmable" to your heart's content also, with 4 mosfets. Sort of a half-way house between backyard-diy opamp+pot and something commercial.
I saw that. Mine would not be quite so fancy on the digital side though. Maybe a better first project though. Scullcom does some nice stuff but it's fairly advanced.
@@uni-byte Yeah great channel, very thorough.
I don’t know why my comments are not being shown here… nevertheless last trial very interesting video about loads and simple passive loads are still useful and underrated at the same time.
Thanks for your comment. Yeah, I don't know why YT does this. I tried 3 times yesterday to post a reply to a video and just gave up. I know that if there a URLs in a post YT will delete it, but my post did not have any URLs, nor any profanity nor did it contain any sensitive subject matter. YT would just not let me post. I'm glad you finally got through and I appreciate the effort very much.
My eyes must be getting old (or RUclips compression has messed up the colours on the resistor colour codes, which seems less likely). The 6 resistors that make up the sensing resistor on the Simple DC Load don't look like 1.2 ohm resistors, which would give the 0.2 ohm 18W resistor on the circuit diagram.
Also, yes a video project building one of these is a great idea. Everyone should have multiple loads in their toolbox, and that one would make an almost ideal beginner project for anyone building up their electronics toolkit.
LOL! Your eyes are not deceiving you! When I drew up the schematic I thought I had a bunch of 1.2 ohm resistors, but it turned out that my memory was not quite right - they were 1.5 ohms, so that should read 0.25 ohms. Good catch.
Oh boy! A lovely load lowdown!
One of my favorite uses for my NanoVNA is for characterizing resistors for RF applications.
I nearly got a free electronic load from a government lab I worked at. It had a bad meter that was only about $20 to fix, but the group manager said to get rid of it. No other group wanted it and since it was broken they were going to toss it out. At the last minute someone in another group said they'd take it. Now I'm glad they did. It was ridiculously expensive, retail price. It weighed over 200 pounds. It would have been a huge white elephant sitting on casters in the corner of my lab. I don't recall voltage and current load capacities, or even the manufacturer. This was about a decade ago, but it had 8 large high-volume fans and a huge heatsink (probably over 50 pounds of aluminum on it.) I recall the spec sheet had some ridiculous numbers on it. It was all a bit much for testing flashlight batteries in what is now basically a hobbyist lab. :)
LOL! It sounds like you dogged a bullet!
@@uni-byte, my HP 524C (55kg) taught me an important lesson.
@@johnwest7993 The importance of a gym membership?
@@uni-byte, pretty close. It taught me that I wasn't Superman, and it taught me what the term 'boat anchor' in electronics really meant.
W = A x V
The OpAmp circuit is my choice. It would have the smallest affect on the circuit under test.
Yes, they can be inexpensive, compact and adjustable too.
So you are an Amateur radio operator.!?
@@snakezdewiggle6084 That's a bit of a story. Let me start by first saying, no .. technically, not yet. I have been threatening for a long time, but I live in a pretty sparsely populated area so there are 1) No local examiners so I can take the exam easily. 2) No one to converse with unless I get some pretty decent gear. I did have the exam set up twice in the past but once the examiner cancelled and the other time I cancelled as the roads were closed due to a winter storm. As it is right now the radios I have are CB, FMRS and those I have limited to GMRS frequencies. All of which can be operated in Canada without a license. Since there is a dearth of radio operators in my area I usually just use the GMRS and FMRS radios on wilderness outings (hunting, camping, fishing, etc..) with friends. I may yet try to set up an exam again .. who knows?
@uni-byte
You have the knowledge and insight into components and circuits. Well spoken, good pitch. It was a toss up between, school teacher or Amateur radio.☺
It has become an expensive hobby unfortunately.
Once you sit and pass the exam, thats your's, for life, like any degree.
You can then pay for a license and callsign.
I've surrendered my license and callsign since losing my radios, etc.
If you know anyone "into" radio, they will your best avenue. Just had a quick peek at your government's page. There is plenty of good info there and links to support. Looks like they have Practice Exams to try out. I think you can sit the exam via video / zoom. That makes it an Open Book exam.
When you have some time, just poke around the Gov' pages.
Its not everyone's cup o tea.
@@snakezdewiggle6084 I do the sample tests every so often and score better than 85 each time. Wasn't aware of the on-line option though.