The rollers are probably the least of your problem, but for a typical solution, see the video at: http://www.intelcotowers.com/video.htm Pause it when they show close-ups of the rollers. They use two
Jorge, First try reinstalling the files (select the Repair option when you insert the CD). If that doesn't fix it, delete the YTW.DEF file located in the directory that hfta.exe is installed. If this
HFTA does allow selecting 9 combinations of soil conductivity/dielectric values, but the impact on the gain pattern is relatively small (0.5-1 dB) in most of the cases I've tried. Steve, W3AHL -- For
I haven't seen a dedicated log-cell yagi program, but a good reference on the subject the is L. B. Cebik's LPDA Notes Volume 2. It has six chapters on the subject, and uses EZNEC models to explore th
I just did an analysis of this for our club's Field Day site for next year, since we had problems running 10A with only 5 watts this year. Someone forgot the bandpass filters (BPF) used in the past,
If you want the wire to rotate down, it must rotate around the X or Y axis, depending on which plane the wire is in. Think of the axis you choose as having an axle going through the end of the wire i
A much better part in my experience would be the Littelfuse TVS diode series, such as: http://www.littelfuse.com/products/TVS+Diodes/Axial+Lead/5KP.html They have 1 ps turn on time, lower clamping vo
The current flowing in each element of a dipole is a result of its impedance. If the impedance is not balanced, neither will the current be. To demonstrate this use EZ-NEC to create a simple dipole a
The manual is available for $9 from: http://www.vintagemanuals.com/manual.php?manufacturer=KLM&model=144-148-13LBA There is some info at: http://forums.qrz.com/archive/index.php/t-51333.html Steve, W
HFTA is easy to install and use, however some find the process of installing MicroDem, downloading DEM files and creating the Weapons Fan radial profiles a little intimidating. I can provide a set of
DirecTV installers do use grounding blocks, but don't recommend true surge suppressors, apparently because most readily available ones aren't rated for their HD service and will decrease HD signal le
While PL-259's and barrel connectors may not have enough loss on HF to worry about, they certainly make nice markers when sweeping coax runs with a TDR! You can see every connector's impedance bump.
I supplied some HFTA plots to the N5ZC, the originator of this thread last night. If anyone else wants JUST the radial elevation profiles but doesn't want the hassle of learning Microdem and extracti
HFTA is limited to a total of 150 data points in the .pro file, including the tower base location. You can increase the total profile distance, but at the expense of also increasing the interval betw
I use Yagi Mechanical from DX Engineering for $39 (there's a free demo version to get a feel for what it does). It does stress analysis for the elements and boom, but also keeps track of the elements
Many counties provide it as a downloadable pdf since it is written into their inspection code requirements. Here's a link to the 2008 version: http://www.garnernc.gov/Publications/Inspections/2008%20
The arrival angle data for HFTA (and VOACAP) are limited to 30 MHz max. However HFTA's ray tracing seems valid at 6M (for 2M I suspect the spacing interval of the radial plots would need to be decrea
I use DX Engeineering's Yagi Mechanical. You design an antenna with a constant element diameter using EZ-NEC or similar. Yagi Medchanical is used to take that design and change the element taper sche
Yes, I guess it could, but why not just model the tapered elements, rather than convert them to single-diameter in the model? It would be less work and possibly more accurate. Steve, W3AHL -- Origina
Wayne, E-mail me your coordinates in decimal degrees to at least 4 decimal places precision and I'll send you a zip file with the radials this weekend. Steve, W3AHL __________________________________