I received my Orion today. I decided to take at look at the filter shapes
of several filters in the Orion. I used a crystal calibrator signal for a
constant source and the Orion S meter to determine the relative strength.
Below is the data I got.
Filter 6 DB width 60 DB width Shape Factor
100 150 440 2.9:1
250 240 470 1.95:1
500 510 820 1.6:1
1000 980 1160 1.2:1
1600 1580 1880 1.2:1
2400 2360 2500 1.06:1
3000 2930 3270 1.12:1
4000 3960 4280 1.08:1
These filters are all very good. I used the same procedure on my rx340 and
found all the rx340 filters have 1.2 :1 shape factors, even the 100 hertz
filter. But the rx340 100 hertz filter has some softening of the CW signal
through it. The Orion 100 hertz filter still sounds fine, exhibiting no
apparent softening of the CW edges. I would say the rx340 CW filters from
300 hertz to 900 hertz are better than the Orion filters of the same widths.
But the Orion Filters from 1000 hertz and up are a little tighter than the
rx340's.
I also put my 250 hertz crystal filter in the Orion. For these simple
tests, no improvement was seen. I also am seeing a 2 S unit insertion loss
from the 250 hertz crystal filter. I had to adjust the center of my crystal
filter 70 hertz to get it exactly on center in the Orion. That means my 250
hertz old filter I've had for years has always been off frequency by 70
hertz. I will be looking for a situation where the 250 hertz filter
improves things. I'll report it when I find one.
I've tried to be objective in my measurements, but my simple measuring
method may not be perfectly accurate but none the less it should give a
reasonable account of the filters in the Orion. The bottom line is they are
very good.
Carl Moreschi N4PY
Franklinton, NC
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