METEOR v 4.0 DOS
METEOR Functions: Starting, choice of the language, Choice Com port for the interfacing Adjust the sampling a critical moment ! Three examples of samplings to know what is the good adjust ! Importance of previous monitoring and pace of echoes on computer screen To what serves the calculation of the length of scanning of the screen, limitation of the number of echoes counted per hour What to serve the small yellow histogram ? How to adjust threshold ? Material change (COMPUTER, RECEIVING and/or ANTENNA) 3 D histogram visualization of the numbering and storage of observations in STA files. You have push by mistake on RESET button, don't panic ! To what do serve the RAW files ? What is their Format ? Input signal lost ?
	At the 1st launching of METEOR the screen of initialization permits you to choose the language.
	Now choice a port Com of your computer which is connected to the interfacing special METEOR then press button com1, com2,...
	Otherwise you are going to see the signal drawing step by step, in the black window, gradually for tender toward the line that indicates " Reference Level ".
Below here are 3 examples of startings with input signal interfacing,  very different.
1st the signal is good and devoid of radio, it is solely the noise from the receiver 2 nd the computer samples too quickly and pass the line of reference. The software corrects and bring back to a correct level. It comes in at least two cases: You use a slow computer 286 - 386 or there were not signal or on-line interfacing in the beginning of the sampling. It is normally without problems. 3 nd below this you must avoid ! The NF signal in input contains a modulation. Are you probably on a radio without the knowledge ? Meteor is going to succeed in sampling but results of observation will be very bad ! After the screen scan use the RESET button. Before restart METEOR verify by ear your frequency ! See advices follow...
The previous monitoring is fundamental. Pass an evening (of bad weather) to listen the noise of your receveir is not very pleasant forcing, it is yet certainly the only efficient means to assure you of the interference missing. It also goes to permit you to value the " quality " of the chosen frequency. Do you hear echoes regularly ?. at least 1 per hour? (Examples of echoes are listen on the Technique page). Otherwise change frequency and try in an another one. Do you detect the passage of airplane above of your antenna ? Don't smile, it is very frequent! At home for example it is the case when airplanes are going to put itself to Montpellier or when hunt airplane pass above low of the village... In this case one hears " to come " progressively a radio, it passes by a maximum, dim then in the same way as to the arrival. in general one hears as the noise of the airplane that is correlation with the observed variation. Normally METEOR avoids the detection of this slow variation type. Echoes of meteors are them to variations very fast.
Classic echo of small amplitude. Strong echo of big enough amplitude. Passage of plane ! It can spread on several windows.
After the METEOR sampling indicates that him calculation the length of scan of the screen. This time varies according to the speed of your machine and the origin of the signal. This calculation is necessary bus on the slow machines the scan is long and several echoes can recorded beings there. METEOR will detect them individually in the limit or him separated of less 10 seconds. (Length that avoided us reasonable). It to a consequence on the numbering: In one hour METEOR cannot count more than 360 echoes. It is therefore the maximum to allocate on the ladder of visualization of COLORGRAMME.
What to serve the small yellow histogram ? How to adjust threshold ? This histogram that occurs again after each of the scan screen is going to inform you of the pace of signals observed. In Abscissa it is about the pixel rank (0 to 255) and in Neat of the Number of rank pixels (n). It is a classic representation in images processing (Restrained numeric value distributed in a picture). In absence of echo, a flattened " histogram " is not a good sign of sampling or quality of input signal.
"normal" histogram Histogram of echoe The red and blue vertical lines, sight the scattering ( see below)
How to adjust THRESHOLD ? It is a very delicate question ! Difficult to automate this stain so much configurations (Antenna + receiving + computer) are varied! A simple means consists in observing variations of the value " Scattering " and to multiply it by 2,3 or 4 according to the level of disruption of the frequency that you use. Only the experimentation (listens + observations) some curve will permit you to adjust your parameters. Note: These parameters are saved automatically each time that you modify the threshold. If you start again METEOR on a new frequency or with a new receiver and/or antenna then press RESET button please !
METEOR v 4.0 DOS constructed a histogram 3D with the progression of observations. The ladder of the histogram is calculate to every change of hour in order to preserve a display adapted to the new observations if these pass the dynamics displayed during  previous hours. It is the visual reflection of data of the .STA file also visualized by COLORGRAMME. This STA files are constructed day per day. The file 11082000.STA contains numbering of the day of August 11, 2000. It is easily a TXT file same to Edit with a NotePad. Data are organized of the following way: 1 st column = hour, then a semicolon ";" then the value numeric correspondent to the numbering. Can she be replaced by a "?" what indicates that METEOR didn't function during that hour. Click here to visualize an example of STA file
You have push on the RESET button by mistake and your histogram left smoked some! Don't panic! Open the directory of METEORV4 you are going to find a file with the extension ". $$$" this file contains your old datas of your last .STA file. Reappoint it, with the date of the day ex: 22072000 + the STA extension. Miracle ! To the resurgence of METEOR you recovered your histogram in 3D !
You can also validate the check box " RAW ". This option allows METEOR to put on the hard drive (in thedirectory of METEORV4) the RAW files. They contain data observed visualized in the measures window (green curve). This or these files will be able to beings visualized whithCOLORGRAMME v 2.0 but they are intended beings' analyzed by COLORGRAMME v 2.0 to h +1 hour. Example: you have record a file between 15h and 16h July 25, 2000. The file himself 25070015.RAW. 25 = day, 07 = month, 00 = year on two numbers, 15 hour of beginning. Colorgramme v 2.0 is going to analyze this file between 16 h to 17h with the more complex analysis functions that METEOR and so possibly to refine the numbering. ATTENTION ! These files are quickly voluminous (100 Ko / h on average) and saturate your hard drive... to the risk " to plant " your machine if you have a small hard drive. See the option erasing after analysis in COLORGRAMME v 2.0.
If input signal lost for any reasons ( disconnect interfacing, NF cut etc...) this message appears. he remains all day long in the window to you inform this event occurred.
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