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Aug 4, 2012:
Some people have noticed a problem with the AIM program incorrectly reporting that files are read-only. Unless the files are on a CD or a write protected storage device, they are not read-only. This may be due to an update to Windows 7, although the exact cause is not known. A way to work around this problem is shown on this page.

It appears this problem has been around for some time. Here's a write-up on it.

(the following information is also in the AIM4170 manual)

Appendix 4 - RS232/USB Operation

The program has been tested with Windows 95, 98, 2000, ME, XP, Vista and Win 7 (32 & 64 bit versions), Win 8.1 and Win 10. It does not require an installation procedure. It will run directly from a CD, a flash drive, or even a floppy disk. If the program is launched directly from the CD, there will be some warning messages that some files are read-only and they cannot be updated. This is ok for a quick functional test on another computer.

Because some newer computers don't have RS232 ports, it may be necessary to use an RS232 to USB adapter with the AIM4170. The AIM's RS232 port uses only three wires. Pin 2 is the data from the AIM to the computer, pin 3 is the data from the computer to the AIM and pin 5 is ground. Hardware handshaking (flow control) is not used. The signal amplitude on the I/O lines (pins 2 and 3) is approximately +/-5V.

The prefered adapters use the FTDI chip since their controller seem to be the most reliable. These adapters are usually more expensive but they can save a lot of time during setup. If your computer is connected to the internet, it may be able to find the appropriate driver automatically when you install a new device.

Array Solutions offers a USB/RS232 adapter that works fine for the AIM4170, AIM4170B, AIM4170C and the PowerAIM-120.

Download the FTDI drivers
For Win 7 click on driver version 2.08.24 (latest driver as of July, 2012)

Installation Guides for FTDI drivers

Using the Device Manager to optimize the USB adapter

If you have an adapter with the chip from Prolific the latest driver is here.
"One VERY IMPORTANT point is that the PC should be DISCONNECTED FROM INTERNET during driver replacement, otherwise as soon as the Prolific USB cable is connected; Windows will look for driver on the Internet and install the previous one that doesn’t work!!! Once the enclosed driver is installed without PC access to the Internet, Windows will no longer attempt to change it, so PC can be connected to Internet again. - F6GNZ"

The AIM program defaults to comm port 1 (serial port). If this is not the correct port, the program enters the Demo Mode. The Demo Mode can be used to view scan files that have been saved, so it is sometimes handy for off-line data analysis when the AIM hardware is not connected.

The comm port assigned to the USB adapter can also be found using the Windows Device Manager: Click Start => Settings => Control panel => System => Hardware => Device Manager. Usually the comm port will have a value of 3 or larger. You can change the comm port number using the Device Manager, Advanced options button. Enter the same number in the AIM program using Setup -> Enter comm port.

If there seems to be a problem with the USB adapter, here are some tips for checking it. First, make sure another accessory in the computer or another program is not tying up the comm port. For example, if the AIM program is started two times without closing it the first time, the second copy cannot use the comm port. This can happen when the first AIM window gets hidden behind another window so it's not obvious that it is still active. Also, check the icons at the bottom of the screen to see if another copy of the AIM program may have been minimized.

When the AIM first powers up, it sends out a character string that can be received by any terminal emulation program, such as HyperTerminal. To use HyperTerminal, which is a standard accessory in Windows, click on the Start button in the lower left corner of the Windows desktop. Then, click "Programs" -> "Accessories" -> "Communications" -> "HyperTerminal". Set HyperTerminal for the following parameters:

Baud rate=57600; 8 data bits; 1 stop bit; no parity; echo typed characters locally.

When HyperTerminal is ready, turn on the AIM4170 power. The green LED on the AIM front panel will turn on and the text displayed on the computer terminal is the following (or similar):

Antenna Analyzer AIM4170
by W5BIG
from Array Solutions

If this is displayed, it means the data from the AIM to the computer is okay. If the text is not displayed, a scope or logic probe can be used to check for pulse activity on pin 2 of the RS232 connector with the PC cable disconnected. Pin 5 of this connector is the Ground pin. The normal voltage at pin 2 is about -5V and it pulses to about +5V several times during a 1 second interval while the text string is output right after the power is turned on. The PC doesn't have to be present at all, so this output test is completely independent of the PC or the operating system.

To check data from the computer to the AIM, type K1 (K and a one). Note the K is upper case. The command K1 will cause the AIM to turn on its Red LED. There is no character space between the K followed by a 1, but the time interval between typing the K and the 1 is not critical. Then, type K0 (K followed by a zero). The Red LED should go off. This indicates the AIM is able to receive commands from the computer; therefore, the I/O data link is working properly.

Recently a problem has been found where Windows does not properly keep track of which comm port is in use. Some problems with the comm port can be solved by removing the port numbers that have been assigned in the past but which are no longer in use. This link has information for cleaning up the port assignments.

The Byterunner adapter works with many computers. However, one AIM4170 user has found that it didn't work with his computer but this one does: HVWTech

Some USB adapters use the Prolific chip. The latest drivers have been found to work with Vista. Some people have found this same driver will work with Win 7 but the FTDI adapter is recommended for Win 7.

USB cables up to three feet long are dependable. Lengths up to six feet work well and their extra utility is worth the slight risk, compared to a three foot cable. If you have trouble with a six foot cable, try going back to three feet. Cables longer than ten feet are not recommended. The quality of the cable is a factor too.

Apr 26, 2016:

Some tips from Alan, WA4SCA:

"My AIM worked fine except for one issue. It would only work on one elderly Dell laptop. On multiple other computers, including a Surface Pro, a white box desktop, and a WinBook, it would be detected and install, but the AIMuhf software would report that the unit was not responding. There is a test using a terminal program in the manual, and that also failed. Over time this covered WIN7, WIN8, and WIN10, both 32-bit and 64-bit versions, with periodic updates of the FTDI drivers in case it somehow got fixed. Despite discussions with MS and Bob, I never got anywhere."

"As you can imagine, this was frustrating, and also perplexing. Unlike the Prolific chips, FTDI chips have a reputation of just working. I did find mentions that in some cases, usually involving USB3 ports and/or 64-bit OS versions, that garbage about the chip could be written to the system which did not get corrected even by removing and reinstalling the driver. I didn't pay any attention since at least two computers I tried were USB2 32-bit, and did work with some other devices with FTDI chips."

"Finally I decided to try the FTDI CDM Uninstall Utility. It removes EVERYTHING, and can be found here:
FTDI CDM Utility

"In each case I ran the utility, took the default and had it do an uninstall, rebooted, installed the latest FTDI driver, rebooted, plugged in the AIMuhf, and shazaam, the software detected the analyzer perfectly after the OS installed it. Three for three computers, so now I have four usable computers. Needless to say, I am a very happy ham."
Alan - WA4SCA

Something very important from F6GNZ:
Both FTDI and Prolific USB interfaces get sometimes disabled by Windows 7 so the unit controlled by them stops to respond. This is due to Win7 disconnecting power to them in order to save energy or when going to sleep or hibernate mode. When this happens, one should extract the USB cable from the PC and insert it again, but it requires some controlled applications to be closed and re-opened again (like DX4WIN logging program). The only way to avoid it happening is described by Joe, W4TV, microHam site manager.

From Joe W4TV:
The following changes in Windows appear to prevent Windows from triggering the bugs [that] cause the lockup:
1) Always set the Windows Control Panel "Power Options" to "High Performance" or "Maximum Performance" depending on version.
2) In the "High Performance" option"
a) click on "Change Plan Settings" and set "Put the computer to sleep" to NEVER.
b) click on "Change advanced Power Settings", select "USB Settings," followed by "USB Selective suspend setting" and set Selective suspend to "disabled"
3) In Windows Device Manager, Universal Serial Bus Controllers double click on *every* USB Hub (both USB Root Hub and Generic USB Hub), select the Power Management Tab and clear (uncheck) the box marked "Allow the computer to turn off this device to save power"
When closing the computer, always do a full (power off) shutdown - do not select sleep, hibernate, or suspend.
These steps appear to prevent Windows from invoking sleep mode or performing any hardware power down actions with the USB devices which are what trigger the crash in d2xx.dll.

Intermittent operation can be caused by the computer getting too busy with other tasks and it can't process data from the AIM. Check other programs that may be tying up the CPU.

Here's a story about a real-world experience.

If all else fails, pull the plug out of the wall! This old trick sometimes works, even in the twenty-first century. (I've seen a couple of HP laptops where I actually had to remove the battery to reset some conditions.) Here's an article related to the USB ports in particular: "USB device not recognized"

Tips for using the AIM with a MAC


YouTube video showing an AIM4170 with a Bluetooth interface.

For more information on the hardwae, refer to the file called: AIM_Options_Guide.pdf
This is included with the zip file which contains the AIM control program.

Several people have found it necessary to set a parameter in the config file to fix the baud rate at 57.6K when using Bluetooth. A short section of a typical config file is shown below with the parameter highlighted:

1 Do not clear each screen during recycle mode ( 1= do clear )
300 Delay in milliseconds while recycling. Several seconds may be useful in some cases.

//**** versions 621 and higher:

change the following parameter from "1" to "0" for Bluetooth, if necessary:
0 parameter_1 future expansion ( recommended for Bluetooth)

0 issue cal warning if long stub is attached while calibrating

This is a list of Bluetooth systems that some people have found to work with the AIM and some that have not worked in a particular instance. This list is not extensive and your results may be totally different since computers differ so much. This is not a recommendation for any particular Bluetooth system.

1. Gridconnect.com - works fine in one reported case.
2. Ezurio BiSM II Bluetooth - works fine in one reported case.
3. KCWirefree Bluetooth - did not work in one case.

PROBLEM: BLUETOOTH may send an extraneous string when it initiallizes, as discovered by one AIM user:

Quote: I made an adapter to monitor the stuff that the 4170 receives. When the Bluetooth connects, the receiver was sending a connect string for some reason. Here is what the 4170 was seeing. Perhaps some of this made the 4170 go to high speed mode.

CONNECT '0009-DD-506F50'
DISCONNECT '0009-DD-506F50'

I found a way to disable it, and now it seems to be working at 57600.

Bob's comment -- The extra character "C" looks like a command to the AIM and it shifts to 115K baud. After that, it won't communicate with the PC because the PC expects it to be running at 57.6K. Make sure the Bluetooth hardware does not output any extraneous characters.

Tips on using the AIM with LINUX

Updated: July 11,2016