[
NEC4WIN95 ] [ NT problems ] [ NEC4WIN ]
Frequently
Asked Questions on NEC4WIN95
General Questions
General questions on
modeling with MININEC
Frequently
Asked Questions on NEC4WIN95
NEC4WIN95
- NEC4WIN95
works
with Win95, Win98, WinNT and Win2000. If you have problems check
the list below. If you can't solve your problem send us an email
and we will be glad to help you.
Installation problems
- Missing DLLs
or OCX at startup
You may have forgot to download and
install the libraries. Download and install one and only one of the two
libraries below.
- The libraries
setup asked me to update my WinNT?
The VB5 library
is a service pack 3 and contains SP3 OCX for Win95 and WinNT.
Some WinNT users may have to install the NT service pack 3. That
service pack is available for free from Microsoft .
Download tip: DO NOT use a site near
you when you download. If you have the choice, use sites in countries
that are in other time zones and asleep at the time you are downloading.
- Windows NT Installation
problems (Eval or Full)
Windows NT security must be set
to defaults allowing current user to install software. If your
libraries are not up to date you will get these sequence of events
and messages:
1st time you run NEC4WIN95
"Unable to locate DLL"
The dynamic link library MSVBVM50.DLL could not be found in the
specific path.
C\ProgramFiles\Nec4win95;C\WINNT\system32;;C\WINNT\system;;C\WINNT\system32;;C\WINNT\;;
Download vb5rtsp3.exe and
after install you get
"The OLE system files are
in use and cannot be updated. The installation
will restart Windows to update OLE. You must re-run the installation
after
Windows restarts to complete the installation"
Restart WinNT and re-run vb5rtsp3.exe
The program should run!
- Printer error message at startup, but
I do not have a printer?
This bug didn't exist before
and seems to come from SP3 library (never occured to Microsoft
that some users may not have a printer). Extra code will be added
to correct this problem in next update.
In the mean time you can fool
the program by installing a dummy printer (anyone will do) even
if you don't have a physical printer connected.
Go to >Control Panel >Printers
and reselect your default printer.
- Installation stops with "ComponentMoveData
failed. Error 119"
Some of the problems you could
have:
- MFC40.DLL may
be missing in \Windows\System. Download from Here
- You have the OCX in you \windows\system
and it is READ ONLY. Check Properties by selecting the file then
right click and select "properties". "Read Only"
should be unchecked.
- You have multiple copies of
some OCX on your system and your registry is pointing on one
that is not in \windows\system
- One of the OLE dlls is corrupt
or missing. The OLEs are used by the self registration process.
Try to reregister manually the
OCX above by going to <Start><Run> and type:
REGSVR32 DLL-OCX name
You should get "DllRegisterServer
... succeeded".
- I can't download some files
Some browsers like Explorer,
have problems to download files when clicking on links. Use the
right mouse button and use the Save as
or Save Target As to download the file.
NEC4WIN95 can be uninstalled
like any true Win95 program. Go to control panel and select
"install/uninstall" then click on NEC4WIN95
in the list of installed programs to uninstall. The program will
be uninstalled and all files removed. If there are new files
created in the directory, directory and files won't be deleted
for security reasons. You will have to clean up manually. Answer
No to "remove shared DLLs" even if windows
tells you that they are not used by any other program.
NEC4WIN95 problems
The demo Splash screen should
have two buttons at the bottom as in picture 1.
If you don't see these two buttons
and have a black border on the right and bottom side your display
uses a LARGE FONTS setup and you should do the following to bypass
or correct the problem:
1. Bypass by typing TAB TAB ENTER
2. Use small fonts on your display if possible.
This problem does not affect
the rest of the program.
- Program complains about a DECIMAL
POINT problem?
Check the page on the decimal
point problem: DECIMAL
POINT
- Program crashes and reports "Error
50003", "Not enough memory"
These errors are generally caused
by DLL and OCX that are not up to date. Check item below on how
to check if all DLLs are here and if they are of correct version.
TSTDLL.EXE
Utility
|
File Name in \system |
Version: |
|
msvbvm50.dll |
05.00.4319 (SP2) |
|
MFC40.dll |
4.1.000 |
|
Asycfilt.dll |
2.30.4265 |
|
Comcat.dll |
5.0 |
|
Ctl3d.dll |
2,31,0,0 |
|
Ctl3d32.dll |
2,31,0,0 |
|
Oleaut32.dll |
2.30.4265 |
|
Olepro32.dll |
2.30 |
|
Stdole2.tlb |
2.30.4265 |
|
grid32.ocx |
1.0.2908 |
|
Threed32.ocx |
1.0.0000 |
|
ComCtl32.ocx |
6.00.8022 |
|
ComDlg32.ocx |
6.00.8169 |
|
Comct232.ocx |
6.00.8022 |
|
Regsvr32.exe |
5.00.1641.1 |
- NEC4WIN95 starts and stops or crashes
immediately
This problem is generally related
to a .INI problem. If you regenerate the INI from the ZIP and
it works once then crashes on subsequent runs it is certainly
an INI problem. Send us an email with a copy of the INI and we
will solve the problem.
If it is not an INI problem one
of the OCX is not correctly installed.
- Sources are moving when I edit my
file in geometry
Sources are attached to pulse numbers, not
wires. If you change the pulse number on wires after inserting
sources or loads they will move to the new pulse location.
Warning: Removing wires carrying
sources or loads when these wires are at the end of a project
can create phantom sources or loads. Try to delete the sources
and loads before deleting wires.
- How do I stop long simulations?
- Click on the stop button in
the main Window. If you are in one of the plots (Impedance,
SWR, Gain, F/B), click first on the window to display the parameters
dialog, this will stop computations. Then on click Cancel.
-
- Can I model adaptation networks?
-
- NEC4WIN95 is derived from Mininec
and will simulate radiating structures but will have difficulties
with electronic circuits. Loads placed in the antenna are OK
but trying to simulate complex feed point adaptation networks
is not recommended.
You can however simulate center
load adaptation (coil across feed point), hairpins, gamma match
if you model them correctly.
Best solution in most cases is
to simulate the antenna without any matching. From the impedance
you can use specialized programs to determine RLC matching network.
- Parallel RLC Loads and zeros
A zero value in parallel loads means that
the component is absent and will be ignored.
- How can I enter R in parallel RLC
traps?
The R in parallel RLC loads is not the Resistance
of the coil but the parallel equivalent. The example below from
exchanges with Tony Field, VE6YP and explains the process:
This is a trap resonating at
7.2 Mhz:
8.2uh 2 ohms
|------L L L L ---- R R R R -----|
---------|
|----------
|------------- C C --------------|
59.59pf
The parallel equivalent parallel
circuit is:
68.8k ohms
|------ R R R ------|
|
|
| 8.2uh
|
-------|------L L L L -----|---------
|
|
|------- C C -------|
59.59pf
The parallel resistance impedance
is:
Rp
= QX
where:
Rp =
resistive impedance at resonance
Q = quality factor of the inductor
X = reactance (in ohms) of either
the inductor or capacitor
Since we have (above) assumed
that a resistance of 2 ohms for with a
reactance of 371 ohms yields a Q of 185.5, then the resistive
impedance at resonance is
Rp = QX
= 185.5 * 371 = 68.8k ohms
And the parallel
resistance is 68.8K!
Frequently Asked Questions
on NEC4WIN
Installation problems
- Using Win95 and GRID.VBX out of date
Q: The program reports that the "version
of GRID.VBX is out of date". I am using Win95...what do
you make of that?
Normally Installation programs
copy the DLLs and VBXs in the \WINDOWS\SYSTEM directory. If they
find that the DLL/VBX exist already they check the date and version
and do not copy outdated versions on top of new ones but this
is not always true. You may have installed a software after NEC4WIN
which used an "outdated" version of Grid.vbx so:
1. Rename the GRID.VBX found
in \WINDOWS\SYSTEM to GRID.VBY
2. Copy the GRID.VBX in found \NEC4WIN to your \Windows\System
directory.
3. Retry NEC4WIN it should work now.
- The program is crazy. I entered 3,795
and I get 3?
Big chances that you using the
European/French numerical notation with a comma ","
as decimal separator and "." as thousand separator.
The program works with US decimal number notation and does not
recognize the comma very well. Go to your Setup International
and change the decimal separator to "." and thousand
separator to "," as in 1,234.56 and it should work.
No need to change keyboard driver.
NEC4WIN problems
- I entered my first
dipole but I have problem with the source and I have a pulse
at one of the extremities?
Your height is zero. When Z=0
the wire is grounded and that is why a pulse was inserted at
one of the extremities. You have two solutions:
1. Enter a height in the Height
dialog (Antenna Options - Height).
2. Enter a height in the Z coordinates.
After entering the height, look
at the antenna and display the pulses. There should be no pulse
at the extremities.
If you want to simulate at different heights, solution 1 is better
because you will be able to change the antenna height in the
Far Field Plot window.
Pulses are inserted between segments,
at wire connections and at ground connections (Z = 0). If your
wire is not connected and not grounded you should have Segments
minus one pulses. If you connect a new wire at the extremity
a pulse is inserted at the junction between the two wires.
A horizontal wire does not have
pulses at the extremities. Check the beams and dipoles and you
will see how pulses are positioned on the wire.
You can experiment by creating
a vertical and changing the height from inside the grid. Look
at the antenna and pulses with View. You will see that
when the bottom of the vertical is not touching the ground, there
is no pulse there. The help file describes that in "Crash
course in modeling".
- How and where do I put the source?
Sources are inserted at locations
where there are pulses, by specifying their pulse position (pulse
number). You can find the pulse number by looking at the antenna
in 2D or 3D and clicking on Pulse and Pulse# (In
the grid click on Show). Pulses are displayed (blue dots)
with their corresponding number.
Once you have the pulse number,
if you are in the grid type S, the sources input dialog
is displayed. Enter the pulse number, don't bother with voltage
and phase with simple antennas, just type Enter until
you see the field Total Sources entered showing 1. Click
on OK and that's it. If you go back to see the antenna in 2D
or 3D you should have a red dot showing the source at the correct
position. If you made a mistake, just click on the source/load
column and change the pulse number to have the source at the
correct location.
- How do I insert a source in an end
fed antenna or a vertical?
Vertical antennas are generally
defined from Z0 = 0 to Z1 = height of antenna. Every time a wire
is connected to the ground, a pulse is created at the connection
and your source should be placed there.
Click on View to look
at your antenna, click on Pulse to see the pulses. If
your antenna base is grounded you should have a pulse at the
bottom. If there is no pulse there, that means that the lower
part of your antenna is not at zero height (Z0 or height
are not zero). Check the 20vert.n4w file to see how a vertical
is defined!
If you want to simulate a vertical
raised above the ground you will have to create a ground connection
by bringing a wire from the ground and connect this wire to the
antenna. A pulse will be created at the connection and you will
be able to insert a source at the connection. There is a catch
however! The vertical section that you created to connect the
antenna to the ground will be part of the radiating system and
that will change the pattern. You can always try to insert an
RF choke below the source but that is not a good solution.
The solution is to create an
artificial ground plane by adding in your simulation at least
2 or 3 radials connected to the base of the vertical and inserting
the source at that junction.
WARNING:
If you use elevated radials,
define the radials first, then the vertical section. It will
be easier to find the pulse number that way. If you define the
vertical section first, pulse one will be located one segment
above the base and the pulse number at the base will be a little
bit more difficult to find.
General questions on modeling with
MININEC
- I changed the ground but the impedance
does not change
In MININEC the ground is assumed
to be perfect in Near Field or impedance calculation.
It is used however in Far Field calculations and Zenith patterns
will vary with changes in ground quality. Load the 20vert.n4w
project and plot the zenith pattern. You will see that the TOA
(Take off angle) is zero and that most of the energy goes horizontally.
The impedance is 36 + j 1.2.
Go to the main menu and change
the ground (Antenna Setup - Ground) to Excellent, Average,
Bad and watch how the TOA goes up with a lower quality
ground. The impedance stays the same but Gain and patterns changed
accordingly.
- Are crossed wires automatically connected?
No they are not. Wires are connected
when the end coordinate of one wire is equal to the beginning/end
coordinate of another wire.
- How do I model ground losses?
You have to insert manually an
equivalent resistive load in the element. Look that the Beacon
antenna. A load has been inserted at the base with 30 Ohms resistance
and an L of xxx microhenries. The L is to bring the antenna to
resonance, but the R is an estimated value of ground losses for
a vertical with a less than perfect radial system. You can extrapolate
ground losses from diagrams on radials system performance like
the one derived from Jerry Sevick W2FMI (in ARRL Antenna handbook,
search for Radials).
- Can I model wire/trap losses?
Yes, by inserting in the wires
a resitive load equivalent to the sum of RF losses, contact losses
etc. Unless your antenna system is completely corroded or made
of very thin wires, resistive losses in antenna elements are
in the order of .1 to 1 ohms. This does not seem to be much but
if your feed point impedance is in the order of 10 ohms that
is a 1 to 10% loss!!!
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