Publications Department
Editor's Note: Some time ago SETI League member Alfred A. Aburto Jr. tested his ICOM model IC-R7100 reciever to determine its internally generated interference profile. His results are presented in this list. In the following article, Rich Tyndall shows how to automate the process of generating a custom radio frequency interference (rfi) database for your SETI station.
My new R-8500 has lots of bells and whistles.. Last night, I found over 450 new whistles. They can be heard at a bunch of different frequencies. Note: SETIFOX has great "Ears". It pulls them out of the hiss with ease. Most of these signals are inaudible. I run another PC/DSP for verification. My hat's off to Mr. Fox.
-----------------------------
CAR.HIS FILE FOR 1.4 Ghz
141938
142169
142179
142189
142279
142435
+447 more lines.
-----------------------------
Here's how I made this file (While I slept).
The SETIFOX.CFG file has a RECORD function that creates a file like SD-JAN03.TXT, this file contains the frequency of any 'Hit'.
The ALARM function sets SETIFOX to call any executable named ALARM.bat/exe/com Directly after a 'hit' is recorded. (Recorded to SD-JAN03.TXT). After the call, SETIFOX resumes its work.
----SETIFOX.CFG file------ (only part of it).
RECORD
ALARM
redraw
;log power
;volume on
logarithmic
repeat
store
;doppler
--------------------------
I renamed ALARM.EXE to BEEP.EXE and made my own ALARM.BAT file.
-----ALARM.BAT--------------
copy *.txt car.dat 'Don't leave any xxx.txt files around.
LH 2line.exe 'Or everyone of them will be copied.
REM LH foxmate.exe
del car.dat
IF NOT EXIST WOW.HIS del *.txt
----------------------------
Line #1 gets me a file with an easy name to open. CAR.DAT is short for
carrier.dat
Line #2 is a QB program used to collect birdie frequencies into CAR.HIS
file.
Line #3 is a QB program used for the actual SETI scan! (REMed off now).
Lines 4 & 5 are for clean up.
After this batch file runs, SETIFOX takes control and resumes the scan.
Note: Line 2 OR 3 should be disabled with a REM.
Here is the QB code for 2LINE.EXE (un-commented version).
REM Part 1 opens carrier data file CAR.DAT and gets 10 bytes of the
freq.
REM Part 2 reads a History file (car.his) looking for a freq match.
REM if no match was found, write new freq at bottom of history
list.
--------2LINE.BAS------- Was named after NASA style Keps.?.
The 1st part opens the newly copied CAR.HIS file and grabs six digits of the carrier frequency off the
second line. (Hence the name 2line).
REM 2Line.bas is mean to be compiled to 2LINE.EXE for use with
REM ALARM.BAT (called by SETIFOX.EXE)
REM 2Line.bas by Rich Tyndall NJ1A 1/2/98 2nd ver on 1/11/98
REM Use this to record QRM signals before performing a SETI scan.
OPEN "car.dat" FOR INPUT AS #1
INPUT #1, a$, b$
CLOSE #1
bp$ = MID$(b$, 7, 10)
OPEN "car.his" FOR INPUT AS #1
DO WHILE NOT EOF(1)
INPUT #1, bh$
IF bh$ = bp$ THEN CLOSE : END
REM If match found, end here..
LOOP
CLOSE #1
OPEN "car.his" FOR APPEND AS #1
PRINT #1, bp$
CLOSE #1
END
---------------
The 2nd part opens car.his (make a starter file) and reads the whole list. If it sees the same freq is already on file, it ends with END.
The 3rd part runs IF the freq is a new one. It appends the new number string to the bottom of the CAR.HIS file. After a few hours, the car.his gets big!
Finally, after all channels are scanned and all the QRM signals are on file, edit ALARM.BAT to enable FOXMATE.EXE (and Disable 2LINE.EXE). Now we can scan for SETI.
REM Use Foxmate.exe for SETI scans.
ab = 3000
'check history file "known" list for match.
'If a match is not found, then here is where we waggle the VCR etc.
END
'---------------------NEC VCR CONTROL SECTION--------------------------
REM' FOXMATE.BAS called by ALARM.BAT (called by SETI.FOX).
REM' By Rich Tyndall NJ1A 1/2/98
REM ver 1.2 1/11/98 change to 10 bytes of freq
REM When Alarm.bat calls here, a Carrier History file (car.dat)
REM is checked Before we go bananas and turn on the VCR etc..
REM We check all 10 digits of the freq and calulate a buffer zone
REM around the freq using the new ab value..
REM We may miss a SETI signal if it's near a QRM signal, but this is
REM the only way to go when you live in QRM city.
'set the ab (audio buffer) in Hz of the ICOM audio BW
'we will use freq+ab as MAX and freq-ab as MIN
'3000 hz should give us a nice leeway.
BEEP
'Get freq from copy of SETIFOX file for compare to known list.
OPEN "car.dat" FOR INPUT AS #1
INPUT #1, a$, b$
CLOSE #1
'Get all 10 digits of freq.
bp$ = MID$(b$, 7, 10)
bp = VAL(bp$) 'convert to real number
MAX = bp + ab 'set max and
MIN = bp - ab 'min values
OPEN "car.his" FOR INPUT AS #1
DO WHILE NOT EOF(1)
INPUT #1, bh$
bh = VAL(bh$) 'convert to real number
IF bh > MIN AND bh < MAX THEN CLOSE #1: END
LOOP
CLOSE #1
'Afterwards, you can (manually?) add the new freq to car.his as needed.
OPEN "WOW.his" FOR APPEND AS #1
PRINT #1, TIME$, DATE$, "WOW?"
PRINT #1, a$
PRINT #1, b$
CLOSE #1
BEEP: BEEP: BEEP: BEEP
' etc, etc
LET tx = TIMER + 10
hold:
IF TIMER < tx THEN GOTO hold
This is another story.
As you can see, Foxmate.bas is very similar to 2line.bas, only when it finds a strange signal, it doesn't write it to car.his file. It gets medieval on the PC speaker.
SETIFOX runs very well on my 568-133, if I don't try to get fancy and display text or graphics while running .EXEs out of the alarm.bat. I am really amazed at how fast 450 frequencies can be checked. But, I would not recommend mapping out the whole waterhole band. In real use, one (10 minute) 2line mode scan should be made with the SETIFOX.CFG setup done, the dish pointed and LNAs fired up before any un-attended scans would be made. (SETIFOX calling Alarm.bat calling Foxmate.exe).
The reason I used only the 1st six digits of the frequency was to provide a large buffer area around the known carriers. A change in the STEP or START parameters might cause a false alarm to occur. Maybe 7 digits can be used..?
If any SETIFOX users have any suggestions (beside learn to program) or comments /questions, Please Email me directly. Is there a SETIFOX Users Group? EUL, Rich
 email the Webmaster | entire website copyright © The SETI League, Inc. this page last updated 28 December 2002 |
 Top of Page |