COM-port assignments for Airmail

Pactor modems are connected to the computer via a “communications port”, either a built-in 9-pin serial port (unusual these days), a USB/serial adaptor, or a direct USB connection e.g. from a PTC-IIusb. COM-port numbers are assigned by Windows as new devices are connected. COM1 will often be a reserved number, even if no COM-ports are previously connected.

Airmail must be set to use the same COM-port number that the Pactor modem is connected to. In the case of a PTC-IIusb, Airmail may have found it automatically, otherwise it needs to be selected from a list of available ports. In any case, if you see an error message from Airmail that initialization failed, or that a particular COM-port does not exist, then the correct COM-port is not selected, or the device was not properly installed and the drivers are not available.

The quickest way to get Airmail’s COM-port set correctly is to use Airmail’s Setup Wizard. With the modem connected and powered on, open the Setup Wizard from Airmail’s Tools menu. Click “Next” until you get to the “HF modem” page (answering questions if this is the first time). If you have a PTC-IIusb then is should have been found automatically– check the COM-port number, and description below the baud-rate box. If you have a serial-connected modem, then click the “Search” button and Airmail will try to find and identify the modem. Click “Next” to finish, or “Cancel” to quit without updating settings.

Another way to check Com-port assignments is with Windows Device Manager. With the modem and adaptor plugged in, open Windows control panel, select small or large Icon view, and click on “Device manager” (for Win-XP, from Control panel select “System”, “Hardware” tab, and then the “Device Manager” button).
In device manager find “ports”, expand that (click the little arrow or “+”), and check for your USB device– it should be listed, with a COM-port number. Take that back to Airmail’s Options window or the Setup Wizard.

If the modem or USB/serial adaptor is not found, then the drivers did not get installed correctly. Look for a yellow “?” or “!” icon, that represents an “unknown device”. Unplug the modem or adaptor from the computer’s USB connector and watch Device manager– it should refresh, and if the yellow icon represents your modem or adaptor then the icon will disappear, and re-appear when plugged back in. That confirms the identify of the device.

USB devices need driver files which have been updated to include your version of Windows. Teh current version of Airmail includes drivers for the PTC-IIusb for all current Windows versions, but the CD’s that are supplied with many USB/Serial adaptors are years old and out of date. Go to the manufacturer’s website, find the “Support” pages and look for driver files, and follow the instructions there.

If you need more help, send a note to and include the type of modem (e.g. PTC-IIusb, etc), what version Windows, and how the modem is connected (e.g. for a PTC-IIex or PTC-IIpro, what make/model USB adaptor), and what you found in Windows Device Manager.

Cheers, Jim