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<DIV> </DIV>
<DIV>I checked out the schematic for the noise blanker: It is not the same as
that for the SB104</DIV>
<DIV> </DIV>
<DIV>If duplicated, it will probably (like the SB104 blanker) introduce lots of
noise. The signal is passed thru an amplifier IC that adds about 8db
of noise. At least that's what the datasheet for the CA3012 says. The
IC was designed to be used in FM receivers where noise is not a concern.
The amp has 70dB gain when run at full and typically was used as a limiting
amp. The signal may overload the following stages, if so you'll have
intermodulation problems as well. </DIV>
<DIV> </DIV>
<DIV>The pot on the panel apparently set the threshold for when the blanker
kicks in. But it seems if set too high even the intended received signal
will not pass. Don't know for sure since I don't have the rest of the
SB303 schematic.</DIV>
<DIV> </DIV>
<DIV>Chris KL7DM</DIV>
<DIV> </DIV>
<DIV>
<DIV>In a message dated 3/15/2014 7:00:53 P.M. Pacific Daylight Time,
pbrickey@verizon.net writes:</DIV>
<BLOCKQUOTE
style="BORDER-LEFT: blue 2px solid; PADDING-LEFT: 5px; MARGIN-LEFT: 5px"><FONT
style="BACKGROUND-COLOR: transparent" color=#000000 size=2
face=Arial>Hi,<BR> I have had quite a few questions about this, so I
thought I would send out the schematic that is in my SB-303 manual.<BR>It is
attached.<BR> 73's,<BR>
Peter<BR><BR><BR>_______________________________________________<BR>Heath
mailing
list<BR>Heath@puck.nether.net<BR>https://puck.nether.net/mailman/listinfo/heath<BR></FONT></BLOCKQUOTE></DIV></FONT></FONT></FONT></BODY></HTML>