Post by wq1p on Dec 4, 2009 7:23:37 GMT -5
Bob,
Terrific job creating the AIM4170. After using MFJ-207/208's coupled with a solid freqency counter, I then acquired the AEA SWR-121. All of these devices "get the job done" for practical purposes; however, they have always left me desiring more data on my installation. I recently began a serious effort to understand and use Smith charts. This quickly led to a search for something to give me reliable data on both my antenna and feedline impedances. While a number of devices will get one into the ballpark, I wanted to get closer to home plate. It was also an equal, if not more important, priority for something that would enable me to educate myself and further my knowledge in this arena.
I was immediately impressed with the basic design philosophy of the AIM 4170. Building a self-contained, portable unit brings with it a host of compromises: Display, range of parameters, computational capability, memory, calibration, accuracy,and cost. A good example is the AEA Via. The first thing that caught my attention when reviewing the Via manual was the statement that the Reactance and Resistance calculations were "indications only" -- no representation as to their accuracy!!
In my opinion, your solution is brilliant -- using the best elements each component provides. First, a rock-solid data acquisition unit, without the inherent inaccuracy of trimmers or pots. Second, software to take advantage of the display, calculation, and memory capacity of the PC. It was not lost upon me that the software has been continuously evolving, thus, providing more capability to be derived from the basic data. I have had my unit for two weeks, and I have not been disappointed. While $500+ would not be considered cheap, it is well worth the expenditure and certainly gives outstanding value. It clearly is a device built by hams for hams!
73's,
John, WQ1P (formerly KC1YT, and in the "old days", WN3/WA3AZW)
Terrific job creating the AIM4170. After using MFJ-207/208's coupled with a solid freqency counter, I then acquired the AEA SWR-121. All of these devices "get the job done" for practical purposes; however, they have always left me desiring more data on my installation. I recently began a serious effort to understand and use Smith charts. This quickly led to a search for something to give me reliable data on both my antenna and feedline impedances. While a number of devices will get one into the ballpark, I wanted to get closer to home plate. It was also an equal, if not more important, priority for something that would enable me to educate myself and further my knowledge in this arena.
I was immediately impressed with the basic design philosophy of the AIM 4170. Building a self-contained, portable unit brings with it a host of compromises: Display, range of parameters, computational capability, memory, calibration, accuracy,and cost. A good example is the AEA Via. The first thing that caught my attention when reviewing the Via manual was the statement that the Reactance and Resistance calculations were "indications only" -- no representation as to their accuracy!!
In my opinion, your solution is brilliant -- using the best elements each component provides. First, a rock-solid data acquisition unit, without the inherent inaccuracy of trimmers or pots. Second, software to take advantage of the display, calculation, and memory capacity of the PC. It was not lost upon me that the software has been continuously evolving, thus, providing more capability to be derived from the basic data. I have had my unit for two weeks, and I have not been disappointed. While $500+ would not be considered cheap, it is well worth the expenditure and certainly gives outstanding value. It clearly is a device built by hams for hams!
73's,
John, WQ1P (formerly KC1YT, and in the "old days", WN3/WA3AZW)