Kenwood VFO-230 User manual

FEATURES
CONTENTS
1.
FEATURES

2
2.
PREPARATION FOR USE 
3
3.
Controls and their functions

3
4.
OPERATION

5
5.
SCHEMATIC DIAGRAM

6
6.
SPECIFICATIONS

7
1.
20Hz-step digital VFO
The digital VFO uses a highly stabilized 10 MHz
reference oscillator. Equipped with AN 8-bit
microprocessor and digital control circuit, the
VFO-230 shifts frequencies in 20 Hz steps simi-
lar to an analog VFO. Unlike conventional L/C
oscillators, the digital VFO provides excellent
frequency stability against temperature change.
No warm-up is required.
2. 5 CH memory circuit
The VFO-230 has its own built-in memory cir-
cuit for further enhancing the capabilities of your
transceiver. The memory circuit accepts fre-
quency input from both the VFO-230 or the
transceiver analog VFO. It is also possible to
call back memory frequencies to the digital VFO.
3. Frequency locking mechanism
A frequency lock switch is provided to prevent
the operating frequency from shifting when the
frequency dial is accidentally turned during
QSO.
4.
Split frequency operation and transmit
frequency setting.
Split frequency operation is possible between
any of three frequencies; the remote VFO,
transceiver of memory frequencies. The
VFO-230 is also equipped with a T-F SET
(transmit frequency setting) switch for checking
transmit frequencies while in receive MODE.
ACCESSORIES
The following accessories are furnished with the
VFO-230:
Instruction manual
(B50-2753-00)

1
Fuse
(0.5A, F05-5011-05, in U.S.A.)
(0.3A, F05-3012-05, in Europe) 
1
Remote cable
(E30-1672-05)

1
Ground cable
(E30-1635-05) 
1
RCA-plug
(E14-0101-05)

Auxiliary foot
(J02-0049-14) 
2
Auxiliary foot mounting screw
(N30-4010-41) 
2
2

PREPARATION FOR USE
Connection to THE TS-830S (see Fig. 1)
Connect the supplied Remote cable to the VFO-
230 VFO OUT connector and to the TS-830S EXT
VFO connector. Connect the ground cable to the
G ND terminals of both units.
Note:
1.
Ascertain that the TS-830S FIX switch is set
to the VFO position (not depressed).
2.
When disconnecting the remote cable, turn the
TS-830S power switch OFF. This procedure
MUST be observed for protection of both the
TS-830S and VFO-230.
CONTROLS AND THEIR FUNCTIONS
FRONT PANEL
1.
MEMORY indicator
This LED (light emitting diode) indicates the
memory circuit is ON.
2.
VFO indicator
This LED indicates the remote VFO is ON.
3.
Main indicator
This LED indicates the TS-830S VFO is ON.
4.
Digital display
The digital display indicates true operating frequen-
cy in the range of 100 KHz to 100 Hz order. In the
case of upper zero blanking and 14,000 MHz, the
lower frequency is displayed as L 999.9. When the
frequency is lower than 3.5 MHz, it is displayed as
L 499.9.

5 MAIN tuning
This control is used to select the desired operating
frequency and changes the operating frequency by
25 KHz a turn. The scale on the control is
calibrated at 1 KHz intervals. The control changes
frequency in 20 Hz steps.
6. MEMORY IN switch
When FUNCTION switch is in the MAIN position,
the Transeiver frequency is stored in the memory.
In the VFO position the remote VFO frequency is
stored in memory.
7.
MEMORY RECALL switch
This switch is used to call-up the remote VFO sto-
red frequency.
8. MEMORY selector
This switch selects the desired memory channel
(channels 1 through 5). Frequency is stored in or
recalled from the selected channel.
9.
RIT indicator
This LED illuminates when the remote VFO RIT
switch is turned ON.
10.
RIT control (Receiver Incremental Tuning)
When the RIT circuit is ON, the receive frequency
can be varied approxmately ±900 Hz, independent
of the transmit frequency. Use this feature when
you party's transmit frequency is shifted or the
transceiver is used for cross frequency QSO. The
RIT functions only when the remote VFO or
memory circuit are operating. The remote. VFO
frequency on the display remains unchanged even
when the RIT adjusted.
11.
FUNCTION switch
This switch is used for split frequency operation
between one of three frequencies- The transceiver
VFO, remote VFO or memory frequencies. Split
frequency operation between memory frequencies
is not possible.
12.
LOCK switch
With this switch ON, the operating frequency can
not be changed. The dial has no effect.
13 RIT switch
The RIT switch turns the RIT circuit ON and OFF.
14. T-F SET switch
This switch is used to receive on your transmit fre-
quency. For details, refer to "T-F SET Switch",
page 5.
BEHR
VFO-230
GND
 le I
AC I 20V
50/60Hz
OGND TERMINAL
FUSE 0 5A

VFOOUT
CAL
-
TVFO OUT CONNECTOR

®CAL
0
REAR PANEL
1.
GND
Terminal
This terminal should be grounded to the TS-
830S GND terminal.
2.
VFO OUT Connector
This terminal should be connected to the TS-
830S EXT VFO terminal using the supplied
cable.
3.
CAL
Connect this terminal to the TS-830S antenna
terminal when calibrating the remote VFO os-
cillator against WWV.
4.
AC power cable
In U.S.A..... 120 VAC, 50/60Hz
In Europe... 220/240 VAC, 50/60Hz
(Selectable)
5.
AC voltage selector (Only in Europe area)
This switches the power transformer primary,
selecting 220 VAC and 240 VAC windings.

e--- FUNCTI ON
RECEIVE
VFO
MEMO
TRANSMIT
MEMO
OPERATION
FUNCTION SWITCH
The FUNCTION switch has three positions, MAIN
(TS-830S), VFO (remote VFO) and MEMO
(memory) for transmission and reception. Its used
is shown in TABLE 1.
NOTE:

VFO-230 is not equipped with the power
switch.
This VFO turns ON automatically when the
tranceiver power switch is turned ON after
cabling.
RX = Receive
TX = Transmit
FUNCTION switch ON
TS-830S
VFO-230
MEMORY
Receive
Transmit
MAIN
MAIN
MAIN
VFO
VFO
VFO
MEMO
MEMO
MEMO
MAIN
VFO
MEMO
MAIN
VFO
MEMO
MAIN
VFO
MEMO
TX and RX
RX
RX
TX
TX
—
—
TX
RX
TX and RX
RX
TX
TX
—
TX
RX
RX
TX and RX
Table 1 FUNCTION Switch Operation
RIT CONTROL
By using the RIT control, the receive frequency can
be shifted by about ±900 Hz without changing the
transmit frequency.
If the frequency of the station you are working
changes, your receive frequency can be reset by
turning the RIT switch ON and adjusting the RIT
control.
NOTE: 
The RIT shift is not displayed on the remote
VFO but it can be read on the TS-830S digital
display.
T-F SET SWITCH
Depress this switch and you will receive on the
transmit frequency without using the FUNCTION
switch. Use this feature during split frequency
operation. For example, when the FUNCTION
SWITCH IS SET AS SHOWN BELOW! IT IS
POSSIBLE TO RECEIVE ON THE REMOTE VFO
frequency by pressing the T-F SET switch.
This enables you to check or listen on the transmit
frequecny during receive operation.
The T-F SET switch is a non-locking (Momentary)
switch. When it is released, the transceiver is
automatically reset as selected by the FUNCTION
switch, thereby preventing misoperation. This
switch is also useful in quickly setting the optimum
transmit frequency for DX operation. The T-F SET
switch does not function during transmission.
5

BACK-UP OF REMOTE VFO
With the power cable connected to power
source, the micro-processor of the VFO-230
keeps operating even when the transceiver
power switch is OFF.
NOTE: 
If the VFO-230 frequency display is abnormal,
disconnect the AC power cable and after
around 1 minute reconnect it.
The display shows 0.0 and the VFO starts cor-
rect operation.
SPECIFICATIONS
Oscillation frequency 
5.40 — 6.10 M Hz
Output voltage

0.2V
+
1 dB
Frequency stability 
Within +1 x 10
-5
at room temp
within +3 x 10 -5
at 0 — 50 °C.
Power consumption 
13W
Power requirement 
AC 120V 50/60Hz (in U.S.A.)
AC 220V/240V (Selectable) 50/60Hz (in
Europe)
Semiconductors used 
Dimensions 
Weight

CPU LSI

1
FET 
1
IC 
29
Transistors  55
Diodes

57
180 (182) W
133 (147) H
287 (330) D mm
(Figures in ( ) include projections.)
Approx. 3 kg
• Specifications are subject to change without notice for technical improve-
ment.

SCHEMATIC DIAGRAM
•
Circuit design and ratings are subject to change for improvement without notice,

o
4..0G(08
le-u-rOr
, «
Model VFO-230
Serial No.
Date of Purchase
Dealer
A product of
TRIO-KENWOOD CORPORATION
6-17, 3-chome, Aobadai, Meguro-ku, Tokyo 153, Japan
TRIO-KENWOOD COMMUNICATIONS, INC.
1111, West Walnut Street, Compton, California, 90220, U.S.A.
TRIO-KENWOOD COMMUNICATIONS, GmbH
D-6374 Steinbach TS, Indiistriestrasse 8A, West Germany
TRIO-KENWOOD( AUSTRALIA )PTY. LTD.
30 Whiting Street, Artarmon, Sydney N.S.W. Australia 2064
® 05108 PRINTED IN JAPAN B50-2753-00 (G)