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I haven't had anything explained to me yet... Though I have gleaned some insight into what the system is used for and how it is designed. :?

You need to re-read your NEETs modules as I don't believe they describe what you are describing. Modulation in simple terms is intelligence applied to a carrier and has absolutly nothing to do with Amplifier bias. In an AM or SSB signal, there are no degrees associated with the modulated...

I'll bet you are measuring PEP and not Average with your power meter. If this is the case, and you are 100% modulated, your Average power is only around 7.5kW for a 20kW PEP signal. This would explain alot since the only true measure of power is average and that is what I was basing my...

Ouch... Glad to hear DC did the right thing.

I was just using 15V because that is what you said (see where I quoted you). As for an alternator being 3-Phase, I know this. If the rectifiers are removed they will generate an AC voltage that can be stepped up with a transformer, but the bottom line is that the laws of physics cannot be...

Let me simplify my analysis. If everything was 100% efficient, and the alternator put out 15 VDC, then the alternators would still need to generate about 1333 ADC for 20kW to be transmitted. Now throw some losses in there, and the bias of the amp, and lets say the system efficiency is around...

Four 12V, 250A alternators produce approximately 12kW. Assumming 100% efficiency, which is not even close to possible, where are you getting the extra 8kW from? I doubt the four 1.5 amp power supplies are doing this unless they are rated at greater than 1333 volts rms. Again, this is just...

Based on alternator, transformer, and amplifier efficiencies and cabling losses, I'm guessing you are going to need a few more than 4 alternators to get anywhere close to 20kW out. Have fun powering that bad boy...

Bob85, I always tune for X=0, and not for lowest VSWR, at the geometric center of the transmit band. You are correct, VSWR does not give a useful indication of effective radiated power. However, maximum power transfer does occur when impedances are matched so if the antenna can be made to have...

If you coil the coax and the coil is tightly wound the coax will be damaged and will not have a 50 ohm impedance anymore. IIRC the radius of the coil of coax must be greater than at least 10 times the coax's diameter, but I learned this so many years ago I am not 100% sure of the values in this...

Did the mfj get grounded at the antenna base when tested? If not, the readings will be off... The source always needs to be at the same potential as the load or the readings are meaningless. As stated by many others, the ideal input impedance of a 1/4 wave properly ground planed antenna is...

I purchased a few items from him and most of his items were exactly as described. The Ham radios I purchased were in good condition, not mint as described, and could have been packaged better - they got dinged up pretty good. Just my opinion. ken

I have no idea... Sorry

base is analogous to gate collector is analogous to drain emitter is analogous to source

Gotcha... :D

Inductors and large resistance values are not very good dissipators of static voltage. While static generated voltages can be thought of as DC, when a connection is made the voltage becomes a very large transient so small resistance values and capacitors make much better snubbers to the large...

X2...

Experience normally equates to expertize... In linear operation, a MOSFET and BJT will dissipate nearly the same power. A MOSFET used as a switch can dissipate less power when the resistance of the channel (drain-to-source) is minimized. This does not mean that ALL MOSFETs will be better...

BJT's are typically cheaper than MOSFET's, though not always... :)

QRN, I agree... :D Lords, do me a favor since you are such an expert... Please download 2 equivalent data sheets, one for a BJT and one for a MOSFET device and then open them side by side. Now look closely at the "Absolute Maximum Ratings" Tables and tell me what you see? I’ll bet...