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Readme File: Hamview 2.05
By Alberto di Bene, I2PHD (dibene @
and Vittorio de Tomasi IK2CZL (ik2czl @


To say it in a few words, HAMVIEW is a program that:

The program was especially developed for radio amateurs interested into all these communication techniques where signals very close to (or more often below) the receiver noise floor are used, like EME, VLF, and so on. However we believe that Hamview will be of value also for HF and VHF CW lovers (try it... we never found a point-and-click CW filter on a commercial receiver!!!), and so on.

All the hardware needed is:

The program was developed in an effort to improve the capabilities of amateur radio communications using the power of digital signal processing, and is continuously evolving. Check the Hamview web page ( ) for further news. If you find some interest in the program, please send an E-mail or a QSL to one of the authors, saying (if possible): This information will not be delivered to anybody, and will not be used for commercial purposes. They will be treated according to current laws for privacy, and have the sole purpose of helping us to improve the next version of Hamview.


To run HAMVIEW, you need the following:

Almost all the video cards on the market today meet those requirements (what?!? Are you still using an HGC card ?!?). HAMVIEW supports all three resolutions, but, of course, the best quality is reached when working at 1024 x 768.


Connect the input audio to the line-input jack of the sound card. Don't use the microphone input, HAMVIEW disables it to prevent stray ambient noise pick-ups. If you want to hear the filtered audio you need of course at least one speaker connected to the sound card output (left or right it doesn't matter, the same signal is routed to both channels).

To invoke HAMVIEW use the following syntax:
HAMVIEW [filename] [-v0 | -v1 | -v2]

The program searches the current directory for a file named HAMVIEW.INI which is used to set the station coordinates, in order to have a correct display of the moon azimuth and elevation (this program is especially targeted to EME users). If the file is not present, a default one is generated, with the station coordinates of I2PHD. If you need to have the moon data displayed correctly, you can change it with a standard text editor. The format is self-explanatory.

Upon starting, you will be presented with the program main (and only) screen. The vertical axis is the frequency scale. The program's range is from 20 Hz to 4000 Hz. Only a part of this range can be shown on the screen. You can scroll up and down with the PgUp and PgDown keys. Near the bottom-left corner there is an input level indicator. Adjust the input level to keep the level in the green part, with only occasional excursions in the red zone. The mouse pointer (a small cross) can be moved, and the frequency corresponding to its vertical position is displayed on the status line.

On the extreme left part of the screen a real-time spectrum-analyzer-like display is shown, updated every half second.

On the central part of the screen a moving bar will paint behind itself the color corresponding to the magnitude of each frequency bin. The higher the amplitude of the incoming signal at a given frequency, the brighter the color of the point shown. Each point corresponds to a bandwidth of 2 Hz, and the bar moves with steps of half second. These values are the consequence of the sampling rate chosen (8192 samples/sec), and the buffer size (two flip-flop buffers, 4096 entries each).

On the right part of the screen there are 9 mouse-selectable large buttons, used to set or reset various functions or parameters. Their color toggles from Red (function active) to Green (function not active) when single-clicked.

From the top:

When the program runs, the following keys are active: All of the mouse-selectable buttons can also be toggled by typing the first letter of the command itself (i.e. 'E' for Estimator, 'F' for Filter), with the exception of Scale, which is toggled with the 'L' key. Case is immaterial.

The status line reports the percentage of CPU used by the program. As an example, with a 225 MHz Pentium this value ranges between 14.4 % with all the functions off and 23.6 % with all the functions on.

For EME operations, a real time clock shows to the operator the two minute periods used for trasmission exchange between east and west stations. To properly set the clock, you must set the environmental variable "TZ", using the DOS command:

SET TZ=< string >

This string is composed of:

Here is an example for Italy, where local time is GMT-1


and if we are in daylight saving time this becomes


Remember: the only important parts of the variable are the number giving the difference between GMT and local time, and the daylight-saving-time indicator!

Every two minutes you will notice that the clock background changes, and a letter "E" or "W" close to the clock reminds the operator which period ("east" or "west") is current. Over the spectrum display the same color is used to trace a thin line, to ease the identification of the stations.

Any remarks, suggestions, praises, complaints, whatever you may have on this program are welcome. Please feel free to contact the authors at the email addresses below.


Here they are.

The authors will not be liable for any direct, indirect, consequential or incidental damages to other pieces of software, equipment, goods, or persons, arising from the use of this software.

The authors are not liable for any possible illegal use of this software, and for any other act arising from the results obtained from the software.

Although the use of the software HAMVIEW is free for the purposes described in the present document, it is *not* a public domain software. The authors retain the full copyright on the software binaries, the source code, and the user interface.

HAMVIEW is a Copyrighted property of:

Alberto di Bene, I2PHD dibene @
via Albignano 28
I-24040 Casirate d'Adda (BG)

Vittorio De Tomasi, IK2CZL ik2czl @
Via Melzi d'Eril 10
I-20154 Milano

(c) 1998

The use of this software is free for hobby and research purposes. If used for commercial or industrial purposes, you must obtain a licence agreement from the authors.

The program can be freely distributed, provided that you don't charge money for this, except for the cost of the transfer media, and that this text document is distributed as well.

The commercial distribution of the software without the permission of the authors is strictly forbidden.

Thanks to Ethan Brodsky for his full duplex Sound Blaster routine.

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