[amsat-bb] Re: echo
jshorney at inebraska.com
Sun Jan 20 15:17:59 PST 2008
On Sun, 20 Jan 2008 13:22:11 -0500, Kevin J. Smith wrote:
>Like Luc I could only barely make out a signal on
>6.7925 but heard the signal on 7.4075 MHz more as continuous signal. By my
>ear I could not distinguish between a ground wave and the moon reflected
>wave, if there was one.
It's really quite simple. According to the information provided on the HAARP
web site, transmissions ran on a 5-second cycle. Carrier for two seconds,
followed by three seconds of silence. Echo return time from the moon is 2.4
seconds. So what you would hear is two seconds of carrier, about a
half-second break, then two more seconds of echoed carrier. This cycle was
repeated continuously through the test period.
My noise level was much lower this morning, but so were signals. Nothing was
heard on 6.7925, but the transmit cycle was heard on 7.4075, peaking S3 with
occasional peaks to S5. I could clearly hear echoes for a period,
occasionally stronger than the transmitter as propogation fades took it down.
Interestingly, every now and then the transmit signal would jump up
signifigantly in strength for a split second. I wonder if anyone else noticed
this? Perhaps something highly reflective was passing through the beam at
Rig was a Drake TR7, 500 Hz filter, Butternut 6-band vertical.
Ham Radio NU0C
TR7/RV7, TR6/RV6, T4XC/R4C, L4B, NCL2000, SB104A, R390A, GT550A/RV550A, HyGain 3750, IBM PS/2 - all vintage, all the time!
HyGain 3750 User's Group - http://groups.yahoo.com/group/HyGain_3750/
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