Elecraft KNB1 Manual User Manual
K n b 1
E
L E C R A F T
K N B 1
N O I S E B L A N K E R
Assembly and Operating Instructions
Revision C, Jan. 18, 2001. Copyright © 2001, Elecraft; All Rights Reserved
Introduction
The KNB1 noise blanker can be used to suppress most pulse-type noise, including that generated
by automobile ignition systems, power lines, and appliances. In many cases, signals that were
completely "buried" in noise will become easy to copy with the blanker turned on.
The noise blanker mode (
O F F
,
H I
,
L O
) is selected using the K1 transceiver’s
N B
menu entry.
The two blanking thresholds provide more versatility in dealing with band and noise conditions.
Refer to Using the Noise Blanker for details.
The KNB1 plugs directly into the K1's RF board with no additional wiring. It is controlled by the
main processor on the control board via the K1's "AuxBus" network. Full circuit details can be
found at the end of this manual.
Specifications
Blanker Type
I.F. pulse detector with wide-range AGC; two threshold levels
Current Drain
Approx. 8 mA when turned on, < 1 mA off
Size
2.0 x 1.4 inches (51 x 36 mm)
i
Caution: Some components in this kit can be damaged by static discharge. Before
handling any transistors or integrated circuits, always put on an anti-static wrist strap or touch any
grounded, unpainted metal surface.