Hi All My 1st Questions is - What the reason of QUIETING in Echo-51 sat? Google gave me a good link of k0nr
http://www.k0nr.com/rwitte/fmvhf.html k0nr wrote
SIGNAL REPORTS FM signal reports are often given in terms of receiver quieting. A strong signal will fully quiet an FM receiver, while a weak one will be quite noisy. A "Full quieting" report is given to a signal which exhibits no background noise or hiss. Signal reports are often given in terms of "percent quieting" to give the transmitting station a better idea of the signal quality.
Remember that when using a repeater there are two communication paths at work -- the path from the transmitting station to the repeater and the path from the repeater to the receiving station. Either one of these paths can exhibit noise due to a weak signal. If the receiving station has a strong S-meter indication but the transmitting station sounds noisy, the transmitting station is probably weak into the repeater. Remember that the signal strength indicated by your S meter is due to the repeater and not the transmitting station.
A frequency modulated transmitter used on the VHF/UHF amateur bands should be set for a maximum frequency deviation of 5 kHz with full modulation. Unlike SSB transmitters, the signal strength of an FM signal is independent of modulation level. That is, a dead carrier produces just as much power as a fully-modulated signal. Excessive modulation of an FM transmitter does not improve the reception of the signal and often degrades it. On the other hand, inadequate FM deviation causes weak received audio. The level of audio heard on the receive end is relatively independent of received signal strength. This means that changing transmitter power does not affect the loudness of the audio at the receive end.
What I have understood
………………………………………………. (FM signal reports are often given in terms of receiver quieting A strong signal will fully quiet an FM receiver)
strong signal (from TX station or sat ) Quieting at receiver side (e.g. ground station) -------------------------------------------------------------------------------------
A dead carrier produces just as much power as a fully-modulated signal PTT on!!! waste of power??? My 2nd Question is Why dose Echo-51 keep pump dead carrier that detected at ground station as quietness?
73's Nader, st2nh www.st2nh.com
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Nader Omer