Best DGRD = 2.1 dB on 25th BUT New Moon on
26th-27th
Sep 9-11
Best DGRD =
1.9 dB on 9th-10th
Sep 21-24
Best DGRD = 2.1 dB on 22nd
Oct 6-8
Best DGRD = 2.1 dB on 6th-8th
Oct 19-22
Best DGRD = 2.1 dB on 19th
Nov 2-4
Best DGRD = 2.3 dB on 3rd
Nov 15-17
Best DGRD = 2.2 dB on 15th
Nov 30-Dec 1
Best DGRD = 2.2 dB on 30th
Dec 12-14
Best DGRD = 2.3 dB on 12th
Dec 27-29
Best DGRD = 1.9 dB on 27th
The best EME conditions occur when:
The Earth-Moon distance is at the absolute minimum and
The Moon is in the coldest sky region (less background noise) along the moon path.
The effect of distance is independent of frequency, but sky temperature
decreases with frequency, up to ~1 GHz and then levels out. The EME
signal-to-noise ratio, in dB, is DGRDaded, from the minimum, by a factor (DGRD,
see below), which varies over hourly, daily, weekly, monthly and yearly time
periods. As a guide for the basic weekend EME conditions the present calendar lists the
expected conditions based on the DGRDadation (DGRD) value. Factors such as local
noise, antenna beam width, side lobes, polarization, etc. can also affect the
s/n ratio of moon bounce signals.
Conditions:
Summary of EME conditions as controlled by DGRD at 50
MHz and New Moon. Conditions may be worse, due to ionospheric disturbance, local
noise and polarity, but not better than indicated.
In general, 50 MHz DGRD:
<1.0 dB is considered Excellent
1.0 to 1.5 is Very Good
1.5 to 2.5 is Good
2.5 to 4.0 is Moderate
4.0 to 5.5 is Poor
and over 5.5 is Very Poor
Within a day of New Moon (NM), high sun noise can make conditions
very bad
regardless of the DGRD.
When two different conditions are indicated for the same weekend, it means
that they change from the value indicated on the left at Saturday's moonrise to
the value indicated on the right at Sunday's moonset. For instance:
Dec 07-08
Moderate -> Poor
means that on Dec, 7th Moonrise conditions are
Moderate and get worse until Dec, 8th
Moonset when they are Poor.