Hi David, Now I see what you mean. Yes, of course. It was a naming issue: I know this as "dead time"! Yes, but in any case it's bad practice to use such a simple switcher without any inductance. Ther
Hi Horta and all, I will chirp in even if it seems rather late in the thread. Don't forget the very definition for the unit of capacitance: One Farad is the capacitance that will change the voltage o
Hi Carl, I have not yet, but might try it soon, with some 10kW power transformers. I'm just trying to learn enough about dissipation in oil to find out how much copper and steel I would save by using
Hi Angel, No, it's not enough. The problem is thermal runaway. If one diode gets warmer, it will reduce its voltage drop, take a larger current share, get even hotter, etc. You would end up with most
Hi Dan, It depends on many factors, but typically it will be a ferrite material with a permeability somewhere between 100 and 1000, and most likely between 200 and 500. Depending on the manufacturer
Hi Carl, A few years ago I needed to make a balun for 160 to 10 meters, that should be able to work at 1.5kW on a transmission line that could have high SWR. After comparing different powdered iron a
Hi Jim, Could you give me an exact URL for some page that gives this information for the 61 material? I couldn't find it, and after a few hours searching I gave up. Living in a rural location, my int
Hi Dan, I would not be so harsh as to stamp them "not suitable", but certainly they are not nearly as well suited for that task as some ferrite cores are. Heating is of course no problem at low power
Hi Bob, Yes, indeed the internal impedance can be quite far removed from 50 Ohm. The heavier the negative feedback is in the amplifier, the lower its output impedance becomes. In many solid state amp
Hi Bob, Yes, indeed the internal impedance can be quite far removed from 50 Ohm. The heavier the negative feedback is in the amplifier, the lower its output impedance becomes. In many solid state amp
Peter, that's interesting information! It's tempting to run the calculator on these chokes: If the turns were quite close together, that would result in a flux density of 23mT at 1MHz, which is sligh
Hi Andy, Marv, That loss might be between 1 and 2%, depending on what line voltage is used (worse for 110V than for 220V, of course). Depending on the situation, that might be acceptable, or not. Exa
Hi Colin, you forgot the DC voltage at the plate in this: In truth, at the tuning capacitor you just have the RF voltage, while at the plate you have the DC voltage added to the same RF. So you would
Dear all, it seems that a little basic information about transformers could be good here. Yes, microwave oven transformers will indeed typically take more primary current at no load, than some other
Hi Angel, Yes, of course they do! This approach generally leads to rather longish transformers (laminastion stack much taller than the with of the center leg). Also, such transformers are more suited
Hi Dave, interesting problem, with those bolts! Firstly, I would not believe that they can get so hot from hysteresis losses. They are not really taking much magnetic flux at all, because they are se
Hi Dino, Wow, that's one big transformer! 3750kVA! That's several times larger than the largest pole mount distribution transformer I have ever seen! Did you really mean such high power? I wouldn't b
Hi Bryan, Good! Old version of the Radio Amateur's Handbook had a chapter devoted to rewinding power transformers, and so in that time many people did it. Without any good explanation, this section w
I too tried to access that web page, first configuring my browser into safe mode (so that it will not execute any script or other code from the website). The result: I get an error telling that the p
Hi Martin, Thanks for that! I downloaded it, and had a thorough look at it. Well, I had thought that there would be some good information about some modern legal limit SS amp design, and then discove