0006005968H80
Joined: | Sat, Apr 4th 1998, 00:00 | Roles: | N/A | Moderates: | N/A |
Latest Topics
Topic | Created | Posts | Views | Last Activity |
---|---|---|---|---|
Calculating Impedance | Dec 9th 2013, 23:56 | 7 | 7,159 | on 11/12/13 |
Latest Posts
Topic | Author | Posted On |
---|---|---|
Calculating Impedance | 0006005968H80 | on 11/12/13 |
This is what creates the uncertainty. It would be worthwhile to eliminate the forbidden lengths, but the side effects might create worse problems than are solved. I hoped there was a formula, graph or table that might give some insight. Unfortunately, although I have EZNEC by virtue of having the 22d Edition of Antenna Book, I do not have enough familiarity to use it..... one of the projects on my list once I get this antenna up and on the air. |
||
Calculating Impedance | 0006005968H80 | on 11/12/13 |
In the process of putting up a ~31' vertical over 36 radials, and in the process of understanding the remote tuner situation, I think I would like to be able to know what the matching impedances the tuner is going to face on different bands. I have the AH-4 auto tuner which reputedly has a range of ~4 to ~5000 ohms. Is this enough? Icom says to avoid half wave wires, but DX Engineering sells a magic box that likely is a transformer to reduce the impedance to within an acceptable range. If you have this ~31' wire, it seems to me it has one impedance at 7.1 Mhz, another at 14.2 or so, yet another at 21.3 etc. Is there a formula or table to ascertain what it is likely to be? |
||
Calculating Impedance | 0006005968H80 | on 9/12/13 |
Is there a formula for calculating the expected impedance of a wire of a given length at a given frequency? Example: with a 45' wire at 7.1 Mhz one would expect the impedance to be matched of what? |