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Sir idol saan po ba ang shop ninyo ?

Apparently the annoying guy is a flat earther. Part of a larger debate "czcams.com/video/pXZDNuknWhM/video.html"

Don't make the bullshit videos you can sue your solar companies that was based in your own country why they giving outsource to foreign country

You are about to enter the courtroom of Judge Judith Seidelin this is Judge Judy

Nice project again.

Wicked circuit, just discovered your channel. Super interesting hearig you justify differenet transister choices and outpout topologies. I believe you were correct about the diode in the original circuit, it is to bypass the resistor in the charging phase and force current through the second half of the pot during discharge. Thanks

Can this be used for guitar amp??

Grabbed one off Aliexpress last year, very handy tool.

So in a nutshell it's another version of famous avr dds r2r generator.

The exposed copper with the time can get corroded

I would started with the 3 visually burnt trasistors and leaky cap before buying a fancy oscilloscope

You got lucky. Bought one about a year ago and it was a wreck both mechanically and electronically. I had to make quite a few corrections including replacing the output op-amps. If your interested I did 2 videos on it #0060 and #0071 over on my channel. It's nice to see some people get good ones!

Seems a pretty useful tool. Thanks for the show.

The up on the left corner I believe adjusting the contrast of the display. And the one on the middle have to do with calibration of the function generator.

I am currently working on that model receiver and have found similar problems with the bad solder joints. Others with this problem have noted that this was one of the first models that Sony made with lead free solder that that combined with the high heat around the preamp modules and other hot components causes the problem. I also suspected a high resistance in the output relays so I did one of my redneck repairs I have done on other amps. I drill a small hole in the top cover of the relay and shoot it full of DeOxIT contact cleaner. It has worked for several months for me in the past.

how is this age restricted

One of the greatest pop bass lines.

I had a similar problem and it happened to be a NAD. Look around for why the opposite voltage isnt getting through to (balance) it. I chased my tail for ages with -27V on the output chasing -ve voltages. Someone on one of the forums suggested I should be looking for missing +ve voltages. I think mine was a shit join on one of the drivers trans . You probabaly already have but, check the work you have done for solder bridges or lifted tracks. The fault wasnt there before so it's something youve introduced. Good luck.

czcams.com/video/0MZBOn49GUY/video.html Problem with a drop of soldering in contact with a LED in the same amplifier.

NAD is crap, don't fix just throw in trash.

These flatearthers have been smoking serious stuff. Real intelligence 😂

I would check the electrolytics. The amplifier is 30years old. That overvoltage may be the cause of the outputs to have gone faulty initially.

one of the filter electrolytics looks like its about to pop

The isolated PSU (USB power) makes this Osc. useful. But Bode plots (Frequency measurements) are important in the audio world. Is it possible to get the internal Gen and FFT function (lots of hidden modes) to work for this in this scope?

Great video. I've question: will this voltage reference work for esp32c3 and hx711? To prevent excitation voltage from interfering with load cell readings?

Ok i see two transistor pushpull But how many transistor have in circuit? Op amp as drivers? Diodes are vbe multplier and phase spliters? Dont havent bias generator transistor in heatsink

Nice intuitive circuit.

The Earth is flat 🌎‍⃠

I had an old window fan that seized like that and all I did was to squeeze some bicycle chain lube at the stem where it meets the casing, then let it seeps, turn the stem a few times and that's all it takes.

You got wrecked dude keep coping

Dextron II ATF contains dissolved bronze and is preferred lubricant for sintered bronze bearings. I have used it in small motors (and these fan motors) bearings for decades, never a problem. Do not ever use Singer sewing machine oil, guaranteed to emulsify and gum up sintered bearings. Cheers.

Quality of jaws aside, these things require way more practice (and patience) than you'd think. It does get better after you crimped a 100, promise. :D

Congratulations! It's been an excellent series to watch and you've done a great job not only building, but teaching along the way. I hope it gives you years of pleasurable listening. Cheers!😎

Good

Thanks for sharing and making the video. Am I seeing inductive spikes on the scope trace? If so, would placing a reversed biased bypass diode (I hope I worded that correctly) across the fan motor help? You mentioned the noise. As you know, a good bit of that could be from the breadboard construction. I also saw in the comments that you are going to have PCBs manufactured. That will answer the question as to if the breadboard is the noise culprit. Please do a followup video with the PCB build and testing. It will be interesting. Cheers.

Awesome design.

Nice project.

You should get those small switching signals relays. Definitely will help you to have a smaller PCB

This is nice! Thanks for the video.

Very nice, practical project.

80s guitar was different... they don't play'em like that anymore.

Unfortunately, the power dissipation isn't evenly shared between the parallel connected 2.2 and 22 ohm resistors. Because the resistors are in parallel, they will have the same voltage and so the 2.2 ohm resistor will dissipate 10x the power since P=V^2 / R. When the 2.2 ohm resistor is dissipating its rated 10W, the 22ohm will dissipate 1W, so the effective load rating will be 44W not 80W...

Nice amplifier. I have the AVR-1306, 70wrms@8ohm x 5, since 2007. Still running beautifully and great sounding. These early 2000 amplifiers still have proper psu's. Good purchase.

I possibly misunderstood you, but I got the impression you said that cross-over distortion was due to "the way transistors work". As far as I understand, crossover distorsion is not present at all when you run a single transistor ( or a tube ) in pure class A, which is the main beauty of it. The cross-over distorsion arises when you run a pair of transistors in push-pull configuration, and bias for class AB operation, i.e. positive half of wave taken care of by one of transistors, negative by the other, and merge the two halves together. The mismatch between the two non-identical ( or non-symmetrical ) halves , or the timing mismatch, gives crossover distortion.

This is not the "correct" way to do this. The ground line is usually connected to the potentiometer as well to create a voltage divider circuit. This might work perfectly well, I dont know enough to say that it is bad necessarily, but from my understanding, it is not the typical way to do it.

Great information, need to watch this several times.

This is an Amazing little sub. I have 2 of them. One stopped working just before covid and took it to a repair shop. This guy lost it or sold it. He asked for proof, so I showed him a photo I took of the serial number of the sub......sitting on the floor of HIS shop. A week later i gave him the original Box with the same serial number. He then gave me $450 for it.

I just got the mt21 as well... Hooked it up to an oscilloscope. And switching noise is really there. The way they implemented the filters is truly inadequate... I got it somewhat looking good by adding my own filters. But it sill looks quite horrible

Why didn't you use the secondary voltage for the soft start circuit, instead of using the primary and creating a specific RC timed circuit that isn't really universal for different projects? Just curious. Switch the primary of the circuit, based off of the secondary voltage rising to a certain level.

Would this be adequate for testing tube amps?