Cw Accessory Interfacing; Receiver Accessories - Yaesu FT-847 Operating Manual

Installation

CW Accessory Interfacing

All commonly-available keyer paddles should work
perfectly with the built-in Electronic Keyer. The wir-
ing configuration for the paddle is shown below.
For straight-key operation, only the tip and shaft con-
nections are used.
Note: Even when using a straight key, you must use a
three-conductor ("stereo") plug. If a two-con-
ductor plug is used, the key line will be con-
stantly shorted to ground.
When using an external electronic keyer, be absolutely
certain that it is configured for "positive" keying, not
"negative" or "grid block" keying. The "key-up" volt-
age of the FT-847 is +5V, and the "key-down" current
is only about 2 mA.
For CW automated keying using a personal computer,
with an external memory keyer providing for manual
sending, it usually is possible to connect the keyed
lines together via a "Y" connector, as shown below.
Check with the documentation accompanying your
keyer and your contest/DX software for any cautions
which need to be observed.
18
A I
CCESSORY NTERFACING

Receiver Accessories

(T
For weak-signal VHF work, including meteor scatter
and EME (Moonbounce), it often is desirable to record
your contacts for future reference. During high-speed
CW meteor-scatter schedules, tape recording (or feed
of RX Audio to a computer) is required for decoding
of the incoming signal bursts.
Connection of a tape recorder, WeatherFax demodu-
lator, or other receiver accessory is easily accomplished
using the DATA IN/OUT jack's Ring connector, as
shown in the illustration below. The audio output level
is fixed at 20 mV with an impedance of 10 k .
R , W
APE ECORDER EATHER
FT-847 O
F D , etc.)
AX EMODULATOR
M
PERATING ANUAL