I'm an English and law undergraduate. It took me 10 years to understand and diagnose simple valve power amplifiers such as the EICO HF87 and HF60, and preamplifiers such as Heathkit WA-P2, and to buy parts to install and get some of them running, or improved. It's a complicated hobby, expensive at that, too!

A note I have to pass along. This is a true story. I met a guy that loved to go to school. He first went to school and took Mechanical Engineering and got his ME degree. He then thought I will got and get an Electrical Engineering degree. He did. That didn't satisfy him. He then went to school on got his law degree. Then he was finally happy. I asked him. Which line of study was the most difficult. His answer was Electrical Engineering. So you are not alone in thinking it is difficult. It can be. Proof from a guy that studied 3 different disciplines confirmed it to me.

It was tough to grasp for me also. After years of playing and schooling (52 or so) I started looking at all circuits as a water fall of current from positive power to ground. All current flows down the circuit from the top of the hill (positive power rail) to the pool at the base of the waterfall (ground). Everything in between the top of the hill and the pool at the bottom is nothing but voltage dividers. Some of the dividers have solid state devices that have a fixed voltage drop across them. Once I thought of circuits like that I was able to decipher circuits more easily. The other tricky part is breaking every circuit system into common small circuit building blocks. Over time you start to recognise simple circuit blocks and how they are tied together. They actually get boring after you get familiar with each circuit lego block commonly use over and over again. It is very satisfying to find a new way of doing something (new circuit) and it makes you keep going in the hopes of finding a new circuit idea that you never saw before. I learned electronics by playing and made things work with lots of trial and error. I have played with electric when I first learned how to take batteries out of a flashlight. Then I started taking classes in school. Now I know how to design a circuit by the numbers and get a circuit to work almost perfectly before any solder gets melted these days. I am jealous of young folks today because it is far more easy to learn about electronics today than 40 years ago. The internet gives access to any info you want in a blink of an eye. Years ago you had to go to the library or hope Radio Shack had datasheets on parts. I contacted Texas instruments and National Semiconductor and lied to them and told them I was an Electrical Engineer (before I was one) just to have them send me databooks on all of their ICs and other semiconductor components. I still have them today and use them (I got them in 1982). Texas Instruments books were actually hardbound text books style books. They are beautiful. Now you just google part numbers. Parts took forever to get if you could find a source for them. Shipping cost a ton and it took 4 to 6 weeks to get things from another state. Now you get stuff overnight or within several days. The learning curve for electronics today is light years faster today than 40 years ago. Dig in and drink the knowledge from the internet and it gets easier to grasp everyday. Every person you learn from will give you a new way to look at electronics and you will develop your own style of understanding in time that is a morphing of multiple peoples views of looking at it. Good luck and enjoy. Learning Electronics has served me in many practical ways and entertained me for 52 years. Hope you get the same from the hobby or life style as I have. Happy electronicing.

Best motivational video on electronics I have ever seen. Thank you, Mark!

Another thing to consider is that seasoned technicians are usually better at troubleshooting malfunctioning circuits than the engineers that design them, because they gain experience in failing circuits more often than the engineers. I used to do "shakedowns" of engineering prototype circuits, and we worked together to develop the best circuit possible.

“Talent is a pursued interest. Anything that you're willing to practice, you can do.” ― Bob Ross Great video, tenacity will win out (hopefully).

The big confusion (I'm at 7:37 & maybe you will mention this later.) is we can see Current Flow from negative to positive meaning the Electrons are repelling away from each other & trying to go where they ain't so packed. But (if I understand it) the standard flow is the opposite, sort of like Hole in transistors. They didn't have the information way back then but needed to pick one direction, & (50%, 50%) they picked wrong.

Another way to visualize electronics is to think of it in terms of a water system. Pressure = voltage, volume = current, restriction = resistance. Electronic components have mechanical analogs. Batteries are pumps. Wires and circuit traces are pipes. Resistors are like the disks in shower heads. Capacitors are storage tanks or water hammer dampers. Transformers are tanks with diaphragms or pistons separating them. Transistors are valves, though controlled by water. The complexity of mechanical devices contrived to perform "electronic" functions quickly escalates. Once familiar with basic mechanical circuit behavior, it may become easier to switch over to electronic components; a means to booting into electronics. A thing that may make electronic circuits harder to understand is timing. While describing what a part is doing, it has to constantly be kept in mind that other parts of the circuit are active, and may influence what is happening locally. Software is easier to to analyze because interrupts and queues can be implemented. It's very difficult to design a real-time program. Analog electronic circuits operate in real time, and as frequency changes, so do circuit characteristics. There's a lot to think about. Learning how to break things down into understandable units or sets is the key. I've probably dug myself into a trench. But I've written this, and it seems a shame to press cancel.

Haven't watched it all, but had to comment. You know what helped me immensely during your 807 build? I used The Gimp to draw a colored point to point diagram of the build coinciding with the schematic. I carefully watched you hook up the wires and drew them in as you proceeded. The places where you did not explicitly show the connection I figured out from the video and schematic. I know that build inside and out by doing this. There is a LOT on the engineering side I do not understand, but from a tech standpoint I have reconciled the schematic to my diagram and the video of the build. I then moved on to my first piece of tube gear, am early 1950s Travler All American 5 clock/radio. I did the same thing, I just studied the crap out of the circuit and sketched out the point to point diagram matching it to the schematic.

Like Dave Jones says - "It IS Rocket science." Electronics is a vast field, what I do is focus on an aspect of electronics that I enjoy or I'm good at so I do a lot of uC's. Thanks for the video - electronics is hard and vast and yes there's a big difference between fixing a amp and designing it and I've been doing this stuff for 60 years and, like you, I learn something new everyday.

Brilliant. I can spew out the reasons why, but here is what matters: You have a positive impact on my students. Legalities prevent me from describing them, but they have had a rough go of it. Just getting their respect is difficult. You are a natural teacher.

This is a great explanation of a difficult subject. Very helpful for me as I'm just starting to learn electronics again after trying before and getting frustrated. Thanks for the motivation!

Excellent Mark! I needed this talk.

My intro to electronics was one of those Science Fair 150-in-one breadboard kits and everything Forrest Mims wrote, lol. Plus some old Sams Photofacts, a Radio-Electronics Master, and such that my dad once used.

Thank you Mark, last week I told myslef I was gonna get serious about learning this stuff and then I found you. I have learned so much already!

Such a great video. So many people new to electronics need to see this!

A great video on getting into the tube world. You do motivate us to try harder all the time. One thing I find with electronics as well is there are so many variables. Tube amps are pretty straight forward going from point A to B, but like you said the later semi-conductor things can have so many if this then this may happen that make them so much more challenging. I do enjoy these videos and again reinforce that it isnt all that hard for most tube amps. Can't wait to the next one. Thank you Mark!

Parts identification, what each does and how they work together in a given curcuit as well as understanding and reading schematics, controlling heat and solder with proper techniques is a prerequisite for any service repair. Knowing the equipment your working on like the back of your hand helps too. But I'm old lol. I've been repairing equipment since tubes were regular fare lol. That's 40+ years for me. There are a lot of common problems that most people can be taught to deal with on thier own with a minimal amount of training. The more you learn and the longer you do it the easier it gets. Just no substitute for time, education and talent.

Mark this was an awesome inspiration to me. You have a down to earth approach to explaining complex things in a easy to visualize way. Im glad I found your channel. Its funny how you mentioned that you were contemplating mechanical engineering as a career. I studied civil engineering, and the math was what did me in. I'm a visual learner, and the only courses I remember were the stress tests, and hands on experiments. I've loved electronics since I was 12 years old, and now in my 50's digging deeper into electronics. Pouring over schematics has been a great help, but breaking each section down by function has been the only way I have rebuilt several of my vintage amps. Your videos are a tremendous asset to me. Keep up the good work

Most important thing is to understand basic electricity and electrical circuits (lots of free learning on the internet). Once you have that down pat, then you can go into electronics. For all practical purposes electronic devices such as transistors and tubes are simply things that control the flow of electricity in a circuit. Always start at at the beginning and lay a good foundation to build on.

Thanks Mark! The way you explain & encourage people that is simply superb!

I'm an extra class ham and have a small amount of electronics experience, mainly with building guitar circuits, so I've been heavily interested (it is literally all I think about) in learning electronics. I know you say to stay away from tubes, but that is something I learned to work on as well hehe.... But I do work with mains voltages when building a household electrical, so I'm safe. But I'm with the same OP, I just can not keep my focus long enough to learn like I do other things.

Awesome! I'm glad you used one of my favorite amps as an example, the old Deluxe

Mark makes a lot of good points, there are many good basic electronics books like the Maker books, if you can't understand the Maker books, maybe electronics just isn't in your wheelhouse, that just is how it is, it's not for everyone. After the Maker books, I would suggest "The Art of Electronics". Not an easy read, but very thorough, I believe Mark mentioned this book in his recommended books video. I bought it and it is really good, but not for beginners! For those that have problems with physics and algebra, your just going to have trouble with electronics. Also, it just make take time to grok electronics, for many people, myself included, it just didn't happen overnight and I learn new stuff everyday, thanks to Mark, Dave Gillespie, Eli, Michael and many other experts on AK and AA forums.

I think I understand why many people have a hard time with the electronics learning curve. It is simply because they do not understand that the signal they are listening to or watching itself, is voltage/current. There is this false notion that electronic devices magically take in audio/video and "power it" --- so the layman is constantly looking for something that never existed in the first place. My biggest epiphany was realizing that an op amp COPIES the small AC signal at the base ONTO the power rails. I thought the input WAS the output, only with gain. It's not, and while the end result is the same, this subtle difference is at the heart of why people struggle with electronics. Just my thoughts.

yup as a painter , who loves music , i have no math beyond algebra , and thus at a loss beyond simple repairs ,;tube replacement , power caps , etc. built MANY speakers over the yrs. want to build the 807 SE .....well , thanks , i'll get there eventually

Mark, awesome video. Thank you so much! Very encouraging!

Very nice video, thank you Mark, love that last part, greetings from the Philippines

Good starter books is the A/C and D/C circuits sold by Radio Shack . I learned a ton from those 4 books

Really a video which gives good inspiration and informations about how to get further on with electronics repair! :-) Thank you so much ;-)

Thanks mark l learn and understand more each time l watch your videos a big thumbs up from a man down under

A/C over D/C can also be found on the plate of a amplifier tube , coupled to the next stage by way of a capacitor

Sams schematics were the go to info source for repairing home entertainment equipment, but there were many errors in the sams that I have found over the years.

#1: Electronics (the "component-level" type) MUST absolutely "fascinate" a person., ESPECIALLY from the age of being a child... #2: You inherit more than just your "good-looks" from your parents (ie: certain types of "visualization" abilities)... #3: One must have MORE gut-wrenching "persistence" to understand., than just plain "patience"... BTW & FYI: >> I do NOT wish to discourage OR demean ANYone., BUT., after 40+ years of doing my absolute best to explain & teach others some of the VERY basic concepts of individual-components AND circuit-level electronics (ALWAYS including MANY hours of "one-on-one" in-person explanations AND mechanically-equivalent analogies)., including giving them photo-copies (in jpg form) of some truly "basic-level" electronics-lessons (from the 1970s., when component-level electronics were FAR simpler)., only a VERY few of my best friends & customers come even close to TRULY understanding., and then being able to retain a few of those concepts for a few days or months., which has then left me more than sadly disappointed for all the persistent efforts on BOTH our parts... :-( :-(

Another very informative video, Mark...Thanks so much!

Howdy. Humans are difficult sometimes. My experience from my working days are not very many professionals will share their skills. What is hard earned is not given away for free. Teachers and lecturers are not much better either. They are often so inflated with the scientific approach one can't understand a word they say. A narcisistic mechanism. Much depends on the purpose of the knowledge one thirsts. For DIY electronics or repair working layman explanations usually are sufficient. If the goal is to be a researcher more scientific approaches are essential. They provide the base on which further insight may be built. Layman and scientific do not exclude each other. Layman explanations provide a way to wrap one's brain around a concept. Later on a more scientific insight helps see the big picture. And yeah. A thirst strong enough will go through bedrock. Lucky us there are Google and KZfaq. If got stuck on something read many Google explantions. In time the veils will open. In time one will be able to separate Google garbage from good Google. Regards.

WOW, I learnt a lot from this video!

For some reason, I was thinking that the 5AR4 (GZ34) had an indirectly heated cathode, while the 5Y3 was directly heated.

Build projects, ask questions.

Great video. May I suggest getting a Heathkit to practice on? They are made to be user-built and so are serviceable. The documentation is outstanding, and they are readily available.

Great video, Mark! Thanks for sharing!

Thank you, sir. Very encouraging!

Thanks for your videos!! I've watched your vids for a while now.

I,m very pattern oriented so electronics is appealing to me. I,m a professional drummer and patterns are everything.

I have a Marantz 4240 Quad receiver that I want to get running again but the schematic has NO voltages on it. The service manual does show how to set the power regulator voltage and the amp audio output voltages with the trimming resistors. That's it.

Its easy for me. Just follow the rules. Start with making an LED light up, then move to transistor switching that LED.

Science fair projects from Radio Shack were fantastic, truly a shame about that company.

I have a question about Surround Sound circuits, the codects, decoding, Dolby, pro logic and DTS, Master Audio, etc. How do they work? Can you do a video on those subjects?

SAM's is still around, but for autos.

Funny, I designed and sold hydraulic systems and do household wiring, these make sense to me, but electronics escape me. I think I am to ADA and just don't have the mind to grasp things I can't logically follow.

6:53 - Not sure what you're saying here regarding voltages: "...they just don't be happen to be sitting at a reference of ground..." Aren't all voltage values shown in a circuit diagram given in reference to ground (or zero voltage)?

I recommend "Electronic Troubleshooting and Repair Handbook" By Homer Davidson, and it only about $10 from Amazon. a very good book for beginners.

Great video! You've got a channel here. Thanks

Thank You

I have an Epiphone Valve Senior that I'm learning on, because it was fairly inexpensive ($50 used from a college kid) and had issues with overbiased power tubes and a bad output transformer. I took initial measurements and the power tube plates were at 435V DC and were at 37mA current, dissipating over 15 watts from the 6V6 tubes. I replaced the output transformer and the 250R common cathode resistor on the power tubes for a 390R, which brought it down a bit, but it is still high, dissipating just under 14 watts on the JJ 6V6S (14 watts max rated) tubes that I put in it. That was the only change that was made to the amp. I started checking voltages at other points in the amp and found that it has around +40V DC on the grids of the 12AX7 long-tailed pair phase inverter. Is it normal for a PI to have that level of DC, or should I be worried that I have (a) bad coupling cap(s)? I have looked at the schematic and traced it through the amp and the signal is feeding to pin 2 from pin 6 of the first preamp tube through a .01uF cap, between which, the signal splits and goes into the reverb circuit (1 x 12AX7), which returns through a .001uF cap to the reverb pot, rejoining the dry signal and going through an additional .022uF cap before it hits the grid (PI pin 2) and through the resistors leading to pin 7 of the phase inverter. I just don't see where any DC could be getting to the grids or why there would need to be DC voltage at those points. I have searched for any info about what the expected DC voltage should be and cannot find any info on the subject, though I was told by one person on a forum that long-tailed pair phase inverters usually see that kind of voltage on the grids and not to worry. That didn't do anything to help my worries, because of the lack of info on the subject everywhere else. Sorry for the loooonnnnggg comment/question.

To learn electronics you need a good foundation in math , along with good analytical skills

I am a commodity manger but do not have any foundation in electronics components. What book do you recommend to a very beginner? Thanks!

lol, I did this backwards, I learned all I could about tube amplifiers, and even built 3 of them....Now im struggling to understand the solid state electronics, and alot of you tube videos on this are so math heavy. I get lost in the math and equations.

Had to laugh when you mentioned you envied the civil and mechanical engineering students. My son is a mechanical engineer and envied the students in civil and electrical engineering at the time because they didn’t have to take fluid dynamics.

Learn Ohms law, no kidding. Not just the formula, you need to dream it.

I don't find it hard to grasp.