Hi Domenico, I8CVS,
I am grateful that you took the time to look at my measurements
und send me valuable advice. I have today sent our correnspondence
to my contact person in SSB and keep you informed about their answers.
I will also study the diagram you attached, to understand, how you
Hi Werner, HB9BNK
I have seen your measurement on spectrum analyser with and without the
passband cavity filter but the result is not satisfactory because you need
to add a notch cavity filter tuned to suck the - 20 dBm offending POCSAG
signal at 147.300 MHz
By the way you can solve the problem
Hi Werner, HB9BNK
In addition to my previous message I found that KVG in
Germany make Frontend crystal filters upon customer
specification in the range 100 to 200 MHz. The only problem
is that they are large and flat only +/- 7 KHz (14 KHz total)
and the insertion loss is 7 dB
Werner Kullmann, HB9BNK expunged (hb9...@uska.ch):
What an amazing responsetime on this list !
(post the question, go shopping, find valuable advice !)
thank you all very much !
Since you have plenty of gainr, one cheap alternative might be to try a tuned
stub inline with the feedline.
To: Werner Kullmann, HB9BNK hb9...@uska.ch
Cc: amsat-bb@amsat.org
Sent: Wednesday, April 27, 2011 8:35 PM
Subject: [amsat-bb] Re: searching advice on low pass filter for 146 MHz
Werner Kullmann, HB9BNK expunged (hb9...@uska.ch):
What an amazing responsetime on this list !
(post the question, go
Werner:
I EMPHATICALLY agree with the advice to turn down the gain. Improving
your IMD will provide much more bang for the effort than trying to find
a filter with a loaded Q of over 100 at 2m.
An easy way (if imperfect) to get it right is to maximize the RF gain
in the Icom radio and then
