The Amp Garage

I just found a really thorough introduction to Thermal Resistance and Heat Dissipation, and I wish I had found this a few years ago. basics_of_thermal_resistance_and_heat_dissipation_an-e.pdf If the Texas Instruments pdf above was too specific for your tastes, this Rohm Semiconductor lesson covers a...

No. If you don't want to take my word for it, listen to Texas Instruments. Here's a lesson from them in how to understand some of the numbers that show up on nearly every single heat generating solid state device data sheet. These same numbers also tend to show up on high powered resistor data sheet...

Something like the dissipation of the single triode within the same envelope of a dual triode tube ECC82.png Franco No, the inside of a vacuum tube isn't a very good comparison. (I could elaborate, but it would take a paragraph or two.) More like 10 watt resistors mounted in air dissipating 9 watts...

Sorry about the double post. I mostly wanted to second what bepone said, for emphasis: From other oscilograms.. it is difficult to interpret your oscilograms, without the schematic and explanation where did you conect and how did you measure.. I can see in your pics something that does look like it'...

I did take some pics of the noise today: IMG_5927.JPG This is the filament waveform without any filtering. I forgot to take one of the line all by itself but they're practically identical. The line being obviously just scaled up from what you see here. Okay, I went back to your first post and found...

The noise is just present on the power line without the amp hooked up. Its pretty much always there and I'm not really sure whats causing it. Can you post a pic of how noisy the wall voltage is without the amp plugged in? You might've missed the bullseye when you described it, but it could still be...

With the voltage split equally between two MOSFET's in series, the voltages on the X-axis will be one-half and the power at each step will be one-half. The power will still peak at the mid-point, but it will be half the single MOSFET power. English isn't my language, please can you explain this thi...

It's really easy to either over or under-explain things when you're talking to complete strangers. To be extra clear: I was and am still agreeing with your assessment that the rectifiers are probably triggering a HF ringing. I think if we could see a picture of the scope trace it wouldn't look like ...

Usually its between 30-50kHz amplitude modulated by the 60hz fundamental. This probably isn't going to change your noise reduction strategy, but I think the noise you're dealing with is probably not amplitude modulated, or if there is some amplitude modulation happening then the description would b...

When parents are too uneducated (and/or busy with three jobs) to teach their kids anything at all, and assume the kids will learn everything they need to know at school, or on the internet... I suppose therians probably isn't as bad as actually believing in witchcraft, right? Would this be a good ti...

It sort of invalidates your whole post. No, it doesn't. I stopped watching because he had started explaining things in a way that is absolutely incorrect because his foundation he had been building on for the previous 15 minutes is full of ignorance of basic fundamental facts. He needs to go back t...

That's an amazing experimental setup for sure, and the video was really entertaining. However, it's educational value feels dubious at best for at least a couple pretty significant reasons. I'm not a college professor, and I'm not really sure what level of competence to expect from people with only ...

You're one or two decisions away from making it work, and where the adjustments need to be made depends on which parts you're already set on. It sounds like you have a pair of 6L6WGB that you're designing for. Are there any other parts that you already have on hand that you're planning on incorporat...

https://frank.pocnet.net/sheets/093/5/5V4GA.pdf I don't know if this datasheet is the same model of 5V4 that's relevant, but it says typical use is a 10uf reservoir and 100 ohms per plate, at 375v rms. A reservoir of 47uf feels like it could lead to some short rectifier tube lives with a 356vac tran...

It sounds like it's pretty reasonable so far, assuming you're also using a power transformer that isn't over the 5V4's 375v rms limit. What power transformer do you have in mind? Another related question is: Do you know how to ensure the PT secondary resistance and reservoir cap don't over-tax the 5...