Elecraft KSB2 User Manual
K s b 2
Elecraft • www.elecraft.com • 831-662-8345
E
L E C R A F T
K S B 2
S S B A D A P T E R
Assembly and Operating Instructions
Revision G, July 2, 2011. Copyright © 2011, Elecraft; All Rights Reserved
Introduction
The KSB2 option provides the Elecraft K2 with single-sideband transceive capability. With the KSB2
installed, the operator can use digital communications modes such as RTTY, packet, SSTV and PSK31 in
addition to SSB voice.
The KSB2 includes a 7-pole crystal filter optimized for SSB transmit and receive. This filter is always used
for SSB transmit. During receive, either the fixed SSB filter or the variable-bandwidth CW crystal filter can
be specified for each of the remaining SSB filter settings (FL2-FL4). The SSB filter can also be used for
receive in CW mode if desired. The BFO is individually programmable for each filter, allowing
considerable flexibly in optimizing settings for SSB, CW, or digital modes. Transmit and receive BFO
settings can be adjusted independently in SSB modes if desired.
Other features of the KSB2 include a programmable speech compressor and basic VOX (voice-operated
transmit) capability. In addition, the K2 provides a Carrier Balance mode in which the SSB transmit signal
is routed directly to the receiver. This mode facilitates carrier balance adjustment, and can also be used with
headphones to listen to mic audio whenever the mic gain or compression level is changed.
A wide variety of 8-pin microphones can be used with the KSB2. A mic configuration jumper block is
provided on the Front Panel PC board (see Microphone Configuration for details).
This manual supercedes relevant sections of the K2 Owner's Manual.
Specifications
Crystal Filter
Bandwidth approx. 2.3 kHz @ -6 dB; 6/60 dB shape factor approx. 2:1
Carrier Rejection
-40 dB or better (typ)
Speech Compressor
Compression ratios: 1:1, 2:1, 3:1, 4:1
Current Drain
10-15 mA
Size
4.1 x 2.2 inches (10.4 x 5.6 cm)
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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.