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PJ-80 to drive a two-way test of the causes of errors and solutions [2009-8-20] |
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Test machine, sometimes found in paragraph 80 UHF two-way test to the machine is not accurate to point to the transmitter antenna, and there are some obvious bias, this is why? How can we identify and respond?
1, when measured to the discrepancies found in the measurement used to point to a number of test machines (the best known accurately measuring direction or a variety of models to the machine) to verify. Showed basically the same as if the error shows that the point of error is caused by external influences, rather than measurement error to the machine itself.
2, in the visible range of the transmitting antenna (preferably away from the transmitting antenna 50 meters above) found that measuring the deviation, the left (or right) direction of rotation around the transmitting antenna from a distance, observe the error of the angle changes, if significant changes shows that the error is caused by environmental impact.
Measured to the training and competition, face the direction of the environmental impact caused by deviations are a lot of. However, most deviations in the range of 10-20 degrees, basic does not affect the general direction of progress and getting closer with the radio off, the error caused by the actual error is getting smaller and smaller distances, coupled with the "volume ratio" and other technology the use of radio to find it a more smooth.
Detection test to the machine direction of the simple way
Measured to get a new machine, the user must×¼²»×¼directional properties, such as field testing and field experience.
1, the choice of venue must be far away from the radio propagation may have a greater impact on the buildings, electrical wires and other objects, but also taking into account the relatively flat terrain, video from a little far (about 100 meters), to facilitate mobile and other factors (such as rural areas, large parks and other factors).
2, the radio should be set up clear objectives in a tree or trees in this a clear sign of flying objects, this is easy to identify the exact position the antenna
3, to set up radio antennas must be perpendicular to the ground.
4, measuring points are usually chosen to distance of about 60-80 meters from the radio and antenna directly to see (or markers). Incidentally, to emphasize one point: on the radio very close (within 10 meters for example) can be measured to understand the direction of drive, volume and other characteristics, but can not be identified in this distance measurement accuracy to the machine direction.
5, the Department should be measured to the machine (the best known and accurate machine direction) in the same measure of control to the point of testing, if the environmental impact due to the formation of the direction of deviation, lateral movement may be a certain distance away from the direction of a good choice of direction-finding point. The direction of error is usually less than 50 as normal. This error has been close to the radio will not cause harm. PJ-80 test aircraft the sound of two small two-way point, the direction of attention at both ends of whether there is any difference in performance should be selected more accurate and clear to use the client side.
PJ-80 to improve the measurement to a simple two-way approach to machine
PJ-80-based mechanical and electrical measurements to a very simple way, the direction of its performance can not fully meet expectations. However, obvious deviation was found a two-way, may proceed from the following aspects to improve
1, to the bar to add the shield coil: coil cutting a length of more than 5mm each side of the copper rich leather (thickness 0. Mm), roll bar and coil wrapped in betweenÍƤclosure of the interface can not be leaving about 1mm of the Gap, and up the seam. Solder a wire to connect the bottom of circuit board ground (this line can not be too long). After the installation of shielding in the antenna will change the resonant circuit, and, therefore, must be required to re-tune machine.
2, PJ-80 aircraft to check the outer shield: The shield is a self-adhesive aluminum (conductive properties not less shielding effect), or self-adhesive foil (conductive performance is better, better shielding) attached to the chassis wall shielding effect of the completion of the two flip fold paper at the top of the shield is not linked to short-circuit and can not be far too distant from the seam should be about 1mm from the left to receive the signal without affecting the role and played the purpose of shielding .
3, inspection of vertical wire antenna (test machine for this line) and magnetic antenna lead is too long, they will play a direct role of bad radio reception.
4, with two-way point of measurement to a small sound when the whip antenna does not need at this time should be compressed back to the antenna, all receive the machines, to reduce the antenna to receive radio waves on the effects of magnetic antenna to improve its direction. |
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