Topband: Help for Preamplifier and RX pass band filters for low bands
sergio.cartoceti at tin.it
Thu Mar 23 16:23:22 EST 2006
Just in case you wish to read the full story, and see some pictures, about my
March/April 2003 QEX article "A High-Level Accessory Front-End for
The HF Amateur Bands"
is now downloadable as .pdf file from my faster personal website at
for your personal interest:
The elliptical-Cauer pb filters are intended only for RX path. Our
preampl shown and tested has
12 dB of gain, enough to compensate well for loss found i.e. in low
I'm also glad that John, ON4UN, mentioned briefly, just the preampl
circuit from my QEX article,
in his latest 4th edition Low Band Dxing book(ARRL).
I recall that another preamplifier, a commercial one, is mentioned as
well in the above book,
beside mine, it looks similar in design and in active devices used
and I believe it is without
noiseless feedback technique so, for that, it has some dBs of more
gain (16dB), but still close in IMD performance
to our preampl (verified by IMD tests) and it is manufactured in USA
by DX Engineering, model is, DXE-RPA-1.
Hope that's of help or interest to someone.
Sergio Cartoceti, IK4AUY (IR4B, AC7PC, and operator at IY4FGM Marconi
<mailto:ik4auy at arrl.net>ik4auy at arrl.net
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