Good question, of course! I've found, in my own experience with
several INRAD filters, that they have lower loss (by the Ten Tec "S"
meter readings on my OMNI's) but I didn't measure carefully. George
Cutsogeorge at INRAD is a competent and honest engineer, and he does
get very good data - best to speak with him personally with technical
questions, he'll give you the real scoop. He's often left the phone to
sweep a filter for me and give me the info I wanted.
For Dave - just watch the tradeoffs. I believe you get "lower" loss
but there are many who can hear a difference in "ringing" behavior
between the two designs of crystal filter. It is lattice filter vs.
ladder filter. I am completely OK with the lattice filters, but there
are others who can hear "better" through storm static with the ladder
filters with the slight higher loss and softer skirts.
Not hard to build a little RF amp for a few db gain in the 9 MHz line
ahead of the 1.8 filter position. I did that once and it worked fine
to have a pair of CW filters. I later found that the single 500 Hz
filter with the audio filter that the OMNI provides was more than
enough and always worked out. I would not modify an OMNI-C for an
extra CW IF filter these days, I really think its adequate as designed.
Just my opinion.
Isn't radio fun? I live for this stuff. Well, this stuff and my
mandolin and bouzouki :-) Irish music....
Clark
WA3JPG
On Aug 22, 2005, at 8:54 AM, Tommy wrote:
At Monday 08:07 AM 8/22/2005, you wrote:
Talk to INRAD folks, their filters aren't near as lossy as TenTec
filters........ It might mean that you use two INRAD's one in the
500 hz position, one in the 1.8,
Dave K8bbm
Dave,
Is your information from your actual measurements or the information
came from Inrad?
Tommy - W4BQF
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