this Pre- Amp looks nice, but ... such a design is useless until in order to
reproduce it, all parts must be to get.
So, what are the datas for the transformer s "wit" "Geel" and "Zwart" and
from where may I get it ?
----- Original Message -----
From: "Victor van kooten" <[email protected]>
To: "blacksheep" <[email protected]>
Sent: Thursday, April 13, 2006 11:22 AM
Subject: LF: preamp
> Hello all,
> since some months I am listening to the 136KHz band with a Icom IC761,this
> is a good HF tranceiver but on longwave it has some intermodulation
> with local broadcasting stations on 675KHz and higher.To solve this I
> a narrowband preamp,also suitable for a whip antenna.Enclosed the
> picture of the filter shape follows.
> B-3 dB : 3 KHz
> B-60dB : 28 KHz
> No more IM problems on any receiver I use.To compensate for the gain on
> 50 Ohm input I use the 20 dB attentuator on the IC761.