External Speaker And Headphones - Kenwood TS-930S Instruction Manual

should be given serious consideration. The crystal lattice
filters in the transceiver provides all the restriction
necessary on audio response, and further restriction in the
microphone is not required. It is more important to have a
microphone with a smooth, flat response throughout the
speech range.
Follow the microphone manufacturer's instsuctions for
connecting the microphone cable to the plug. With many
microphones, the push-to-talk button must be pressed to
make microphone audio available. For VOX operation, this
unwanted feature may be eliminated, if desired, by opening
the microphone case and permanently bridging the
contacts which control the microphone audio.
Standard microphone sensitivity is within the range of
—50 dB to —60 dB. If a microphone having a higher
sensitivity is used, the ALC and compressor circuits may
not function properly. In this case, insert in the mike line an
attenuator as shown in Fig. 3-2C. A typical MIC gain
control setting is 12 o'clock. If you must rim this control at
9 o'clock or less, use an attenuator.
3.6 KEY
If CW operation is desired, connect a key to the KEY jack.
Use shielded cable, and a standard {mono or 2P) phone
plug.
3.7 EXTERNAL SPEAKER AND HEADPHONES
Receive audio output from the TS-930S is 1.5 watts at 4
to 16 ohms. The TS-930S has a built-in the speaker, plus
an external speaker jack on the reat panel. The speaker
may be an 8-ohm permanent-magnet type, 4 inches or
larger. The internal speaker is disconnected when an exter-
nal speaker is used. Headphones should also be 4 to 16
ohms impedance. When the headphones are connected to
the front-panel PHONES jack, the speaker is disabled.
3.8 GROUND
To prevent electric shock, and reduce the possibility of TVE
and BCI, connect the transceiver to a goad earth ground
through as short and heavy a lead as possible.
3.9 ANTENNA
Any of the common antenna systems designed for use on
the high frequency amateur bands may be used with the
TS-930S, provided the input impedance of the transmis-
sion line is not outside the capability of the AT-930
Automatic Antenna Tuner pi-output matching network.
The transmission line should be coaxial cable. An antenna
system which shows a standing wave ratio of less than
1.5:1 when using 50 ohm coaxial transmission line, or a
system that results in a transmission line input impedance
that is essentially resistive, and between 20 and 150 ohms
will take power from the transceiver through the AT-930.
If open wire or balanced type transmission fine is used with
the antenna, a suitable antenna tuner with balun is recom-
mended between the transceiver and the feed line.
Methods of construction and operating such tuners are
described in detail in the ARRL Antenna Handbook, or
similar publications. For operation-on the 160, 75 and 40
meter bands, a simple dipale antenna, cut to resonance in
the most used portion af the band, will perform satisfac-
torily. For operation on the 10, 15 and 20 meter bands, the
efficiency of the station will be greatly increased if a good
directional rotary antenna is used. Remember that even the
most sophisticated transceiver is useless without a good
antenna.
CAUTION:
Protect your Equipment ~ Use a LIGHTING ARRESTOR