Gain of the antenna, band conditions etc have nothing to do with db gain or loss when turning an amplifier on or off. Db is an expression of differences in power levels. It takes 2x the power to have
No such thing as a "voltage" db verses a "power" db. It is all the same. The db is an expression of the ratio of one power level to another power level. 2 times the power is a 3 db increase in power.
Maybe someone could enlighten me on how mounting a boom on either side of a mast cancels any torque?? 73 Gary K4FMX _______________________________________________ ___________________________________
Just because they are a "broadcast station" doesn't necessarily mean they knew what they were doing when they built it. I know of a station that is built on top of a large rocky hill. It has terrible
I hate to start something here,, but where does the "0.18 dB additional loss come from with any length of line"? Mismatch in and of itself does not necessarily represent loss. 73 Gary K4FMX ________
A 1/2 wavelength (or multiple of) of 75 ohm hardline could be used and when hooked to a 50 ohm antenna, 50 ohms will be seen at the other end of the 75 ohm line. 73 Gary K4FMX _______________________
Yes Bob, that is exactly right. My point was that you can not express any additional loss due to mismatch unless you know what the matched loss of the line is in the first place. Just to say that "w
I think what a lot of people don't understand about open wire line is how it accomplishes its "low loss" and doesn't care if the swr is high or not. It has to do mostly with I squared R losses in the
That is not applicable to this situation: "Mismatch loss is the ratio of power delivered, to power available" That (mismatch loss) is speaking of a load impedance not matching the source impedance s
Hi Jim, I see where you are coming from now. In my last response I thought that you were talking about loss because of a mismatch to the generator and the generator could not put out full power beca
Assuming you are talking about a lightning ground. The tower by itself is not a good ground, as described. It can be considered a supplemental ground rod and should have several ground rods installed
That comes from the fact that when buying copper, strap gives you more surface area and lower inductance than round wire for a given amount of copper cost. And for those that would advocate copper pi
Polyphaser was recommending using copper strap long before they were selling it. They only started selling it as a convenience to customers that didn't know where to get it when buying their other pr
That is not exactly why PP suggests a maximum of 70 feet of ground wire. The reason is that the long wire becomes too inductive to be of much use when longer. But that will vary with the type of soi
I think that he was referring to the end result of the total circuit. It may have capacitive and inductive components in it but the capacitive ones will exhibit a negative reactance and the inductive
Probably not usable out of the design range. The Polyphaser devices have a series capacitor in them. On UHF it is a rather small capacitor and I don't think it is large enough for HF to pass. The hig
Polyphaser has used gas tubes in their coax protection devices from day one. The reason for the series capacitor is to allow the gas tube to fire before enough energy is passed into the circuit follo
Well, I may be wrong too! I haven't been associated with Polyphaser for about 10 or 15 years. The original company was sold several years ago and I had heard that some of the products were made cheap
Maybe some confusion here? A typical AC/DC motor has the fields wired in series with the armature. This allows the motor to run on either ac or dc voltage as it does not depend on the rotating fields
A vertical above your beam will not work. An elevated vertical must have resonant radials. 73 Gary K4FMX _______________________________________________ ______________________________________________