Love it Tony.. this is going to be a great series. Especially love the knowledge of sub's and modding to improve or get around the unobtanium situations ! Happy and healthy New Year to you. I do like the multi-series of shorter vids.
😎 Cool Thanks for doing this (1280) again! I'm actually listening to this through my 1280 😊. I have the one with the International voltage selection in the back panel. Some do not have this.
Happy New Year Tony. Your videos of the past year are much appreciated and excellent (as usual). I use makeup removal pads for cleaning damped with 99% alcohol. Cheap and excellent
Well, I am feeling bad today. It's not a cold. Stomach a little upset and I feel a bit dizzy. Sucks I have to go get a regular prescription, too. Clearly Pioneer was thinking ahead. You can see the outline of a microSD card where the Pioneer name is on the boards. Hahaha. I'll go check out more of your transistor videos. I've never seen those types before. Happy New Year.
Pioneer must have had a deep partsbin since each borad doesn't match exactly... I've done several early 90's Acurus poweramplifiers, and in almost every amplifier one will find different part-brands (same values though) used for one channel then the other. I never found difference between the channels when measuring should be mentioned, but always wondered if they went short on supply and ordered widley to keep stock on parts😅 //Good video👌
Hi Tony. I am sure that the paint type coating on the heat sink assemblies interferes with metal to air heat transfer! I would expect that stripping the coating off them and maybe black anodizing them would improve thermal management.
Emissivity is only a very small percent of heat sink effectiveness. Area is 50x more important. Coatings are for corrosion resistance and appearance. The difference between black anodized, black enamel, black lacquer, or plain aluminum is not worth the time to measure - smallest tiny draft or orientation (convection) require laboratory test conditions - a bumblebee would mess it up.
One of the most interesting videos I have seen about the transistors. One would think there are standard practices out there. Pioneer claims ISO9000?????
Happy New Year Tony!!! :) . The red caps you are using are Wurth's right?. Do you know that these guys make just about everything fron dish soap to parfumes?. I'm not sure i'd thrust em for caps...
That's what he's working on in this video. The big transistors on the black heat sinks are the finals. The circuit boards have the multiple stages. Basically, they have a differential pair and then multiple sections of current amps, one driving the next. Each big black heatsink and the circuit board is the power amp for one channel.
Tony I know one thing about the difference between products made in JAPAN and others made in China. I remember in the old days that goes back in the 70's, Americans had this thought that products from Japan was garbage similar to what we think of today with products from China. It sad that Japan does not manufacture the electronics you are working on today. I know that the design was a product of American ingenuity. Today we do have that anymore. Anything you buy today is made to be thrown out.
Are broken mica pads a huge problem? I've seen some old amps with broken pads (not fully delaminated nor fully broken in pieces) and they seem to work just fine? I guess the temps could be a problem if the amp is driven 100%? Best wishes from germany!
I usually replace any mica pads that have cracks in them. While they will most likely still work (as long as they aren't cracked all the way through), I don't want to risk them cracking further and allowing the transistor case to short to the heat sink.
