Kenwood TS-780 User Manual

You are the owner of our latest product							the new TS-780 Duo Band Transceiver.
This		unit	has	been	carefully	engineered	and	manufactured	to rigid	quality Standards,
and	should give			you	satisfactory	and dependable		Operation for	many	years.
We		suggest	that you read this instruction				manual carefully from cover to cover to insure
the	maximum		Performance and			trouble-free	Operation of your		new model TS-780.

Save the shipping box and packing in the event your unit needs to be transported for remote Operation, maintenance, or Service.

	CONTENTS
SPECIFICATIONS .............................................................................................		2
1.	FEATURES ................................................................................................	3
2. BEFORE USING ..........................................................................................		4
3.	CONTROLS AND THEIR FUNCTIONS .............................................................	5
4.	PRELIMINARY.. ..........................................................................................	9
5.	OPERATING INSTRUCTIONS .......................................................................	.1 1
6.	OPTIONAL ACCESSORIES ..........................................................................	.2 1
7.	TROUBLESHOOTING .................................................................................	.22
BLOCK DIAGRAM.. ..........................................................................................		.23
SCHEMATIC DIAGRAM ....................................................................................		.24
TOP § BOTTOM INTERNAL VIEWS.. ...................................................................		.27

3-l.	FRONT PANEL
1	F. LOCK Indicator

This indicator will light when the LOCK switch is turned ON (VFO frequency is locked).

2 BUSY Indicator

This indicator lights when the squelch is open in FM or.FM-

CH	receive mode, allowing the Operator to check whether
the	other Station			is	transmitting.
3 ON AIR		Indicator
This	indicator		will	light during		transmission.
4 OFFSET		Indicator
This	indicator		lights		when the	TX OFFSET switch is set to
the	D - A	or	D	-	B Position	for	repeater Operation.
5 M e t e r
This	meter	has four functions, each					being selected		by using
the	meter select			switch.
RFIS:		The meter serves				as	“S”	meter indicating the
		strength of received				Signal		on a scale graduated
		from 1 to 10 (FM),				or	1	to 9, 9+20	dB and
		9+40		dB (SSB CW).

	F. LOCK Indicator
2	BUSY		Indicator
3	ON AIR Indicator
4	OFFSET			Indicator
5	Meter
6 TX-OFFSET Switch
7	REV (Reverse) Switch
8	TONE Switch
9	LOW POWER Switch
10	NB	(noise		blanker) Switch
1 1	Meter		Switch
1 2	VOX Switch
13	Standby			Switch
14	POWER Switch
15	MIC Connector
16	PHONES			Jack
1 7	MODE Switch
18	PRIO.		M	Switch
19	TIGHT Level
2 0	F. STEP			Indicator
2 1	Tuning		Knob
22	FUNCTION Switch
23	MEMORY Selector
24	S S B	M I C
2 5	RIT Indicator
26	RIT	Control
27	IF SHIFT			Knob
28	S Q U E L C H C o n t r o l
2 9	SCAN-W
3 0	AF GAIN Control
3 1	RF	GAIN		Control
32	F. STEP Switch
33	RIT Switch
3 4	SCAN Switch
35	H O L D
36	M. S Switch
37	BAND Switch
38	M (Memory) Switch
39	F. LOCK Switch
4 0	M. R	(Memory Recall)

Switch

During transmission, the meter indicates RF output.

ALC/CEN: In FM receive mode (MODE switch in FM, FM-

CH position),	the	meter	functions as		a Center
meter. Turn	the	VFO	knob	to your	desired
r e c e i v e Signal		u n t i l	t h e	meter pointer i s
centered.

In other operating mode (SSB, CW), the meter indicates the transmitter ALC voltage. In SSB

Operation, adjust the MIC gain	control so that
the meter pointer deflects within the		ALC	zone
on the scale. In CW Operation,	adjust	the	CAR.
L knob.

6 TX-OFFSET Switch

This switch is used to shift the TX frequency from the RX frequency for repeater Operation. After the repeater opera-

tion, it	should be set to the SIMP Position;	the	TX	frequen-
cy will	coincide with the RX frequency. In	case	of	Off-band,

the frequency is not shifted and the transceiver is set in simplex mode.

5

5-5 CW Mode

Reception

Set the controls and switches as outlined in section on

“FM Mode”, except	that the MODE switch should be set
to CW. For reception,	proceed as follows:

1. Turn the POWER switch ON and adjust the AF GAIN control for suitable volume.

2. Turn the VFO knob slowly for the desired receive Signal

so that a 800 Hz beat is heard. In this way, the frequency of your Station will coincide (Zero-in) with the fre-

quency of your party’s Station.

Similarly, if your Party calls back with a 800 Hz beat in response to your call, it means that the party’s frequen-

cy has coincided with your frequency. Note:

The 800 Hz beat can be checked by using a frequency counter.

Transmission

Adjustments of the transmitter for CW Operation are

basically the same as for FM Operation. The transceiver will be ready for use when adjusted in FM mode provided that the frequencies are the Same.

For transmission, set the controls and switches as outlined in section on “FM Mode”, except that the MODE

switch should be set to CW and the meter switch to ALC/CEN. Connect your key to the KEY jack on the rear Panel.

1. Check to ensure that the MODE switch is set to CW. Set

the standby switch to SEND		and the ON AIR indicator
will light. Under this condition,			press the key down and
the ALC	meter should deflect.		Set	the standby	switch
back to	REC Position.
Note:
If the key is not connected,		the	ALC meter will		deflect
when the standby switch is		set	to	SEND.
2. Adjust the CAR LEVEL control
With the standby switch in		the	SEND Position,		adjust
the control so that the ALC		meter		deflects within the
ALC zone when the key is pressed down.
Then, release the key. Set the standby switch back to
REC Position and the meter		switch to RF/S Position.

Note:
If there is a Change in ALC		meter deflection, reset in the
Same	manner as in the SSB mode.
3. Adjust the side tone
The	TS-780 has a built-in side tone circuit for monitor-
ing	your station’s CW Signal	during transmission. To		ad-
just	the side tone volume, open the top		cover and	turn
the SIDE TONE control for desired level.
This	adjustment should be made in receive mode with
the	key pressed down (standby switch in		REC position),
since, in so doing, the side		tone circuit	is activated.

Use of RIT Switch

For detailed information, refer to section on “FM Mode”. Use the RIT switch when your party’s frequency has deviated from 800 Hz or you wish to transmit with a different beat frequency.

Use of NB Switch

Refer to section on “SSB Mode”.

Use of RF GAIN Knob

Refer to section on “SSB Mode”.

Use of IF SHIFT Control

By using the IF SHIFT in conjunction with the RIT, tone quality can be adjusted.

Semi-Break-In	Operation
The TS-780 is	capable of semi-break-in Operation,	in ad-
dition to the usual CW Operation with the standby		switch.

The semi-break-in uses the side tone to activate the VOX circuit which switches to transmit when the key is pressed down and to receive when it isreleased. For semi-break-in Operation, set the MODE switch to CW and the VOX switch to ON. Other operating procedures are the same as for the usual VOX Operation (Refer to 5-6).

Side tone is heard

-	from	-	l
	-

Fig. 15 Semi-break-in Operation

14

5-6 VOX OPERATION

The VOX is an automatic switching System that swit-

ches the transceiver to transmit and receive while speaking into the microphone. This is mainly used in SSB mode.

With the VOX switch set to ON, the transceiver is

automatically switched to transmit mode when you speak

into the microphone and to receive mode when you stop

talking.	For VOX Operation, the standby switch should be
set to	REC.

Control Settings

1.Adjustment of VOX GAIN Control

With

the

standby

switch

set to REC, place the VOX

switch in the VOX (ON) Position.

First turn the VOX GAIN control

clockwise

and adjust it

so

that

the transceiver

is switched to transmit mode

when you speak into the microphone with normal voice.

Turn

the

control

further

clockwise and the gain is

increased allowing the transceiver to be switched to

transmit mode with a lower level

of

voice. However,

excessive VOX gain results in misoperation by ambient

noise.

The condition

of VOX Operation

can be checked through

the speaker. When any

Sound is heard from the speaker,

it means that the transceiver is in receive mode; other-

wise, it is in transmit mode. In

transmit mode, the ON

AIR indicator Comes on and, in receive mode, the light of

indicator

goes

off.

2. Adjustment of ANTI VOX GAIN Control

This control is located on

top of

the

case

(sec page 9)

and is used to prevent the VOX circuit from being

misoperated by the Sound of speaker.

Adjust the VOX GAIN control as directed in item (1)

above. Then, adjust the AF GAIN control for suitable

volume

while receiving Signals

from

a

Station.

Hold the microphone 20~

30 cm from the speaker and

adjust the ANTI VOX GAIN control until speaker Sound

will

not

activate

the

VOX circuit.

Excessive

turning of

the

control in

clockwise

direction

will Cause the ANTI

VOX circuit to operate, resulting in failure of the

transceiver to

be

switched to transmit

mode.

3. Adjustment of VOX DELAY Control

This control is used to hold the transmitter on after VOX

Operation. If the hold time is

too short, the TS-780

returns to receive whenever you pause speaking. If too

long, the TS-780 will not

return to receive after speak-

ing. Adjust the control so that the transceiver holds pro-

per transmitting time when you speak at normal Speed.

This control is also effective

for

CW

semi-break-in

Operation.

During

CW Operation,

do

notturn the control excessive-

ly in clockwise

direction,

as it takes a long time until the

transceiver returns to receive when the key is released;

making

it

impossible

to

perform

smooth

semi-break-in

Operation.

Note:

If the VOX switch is left ON, the TS-780 will momen-

tarily	transmit when	the	POWER	switch	is	turned on.
After	VOX Operation,	set	the VOX	switch	to	OFF.

5-7 READING THE FREQUENCIES

The TS-780 digital display indicates	carrier positions in
all operating modes. Because of the use	of a special circuit,

the carrier Position remains the same when the MODE switch is manipulated, thus the transmit and receive fre-

quency can be directly read				on the digital display, except
for	CW reception		where the	frequency on the display is
higher by the beat frequency				(800 Hz: see	section on	“CW
Mode”) than the transmit frequency.
Note:
The	digital	display	does not	indicate the	frequency	varied
by	the RIT	knob.

5-8 BAND SWITCH (UP-DOWN)

The BAND switch consists of two pushbutton switches,

UP and DOWN. By pressing the UP switch, the frequency is

shifted up by 1 band and, by pressing the DOWN switch

the frequency is shifted down by 1 band. By holding either switch down, the frequency is shifted continuously at 0.5 seconds intervals. As shown in the illustration below, the

BAND	switch functions		separately	for	the VFO A and B
(sec section		5- 9 on	“Operation	of 2	VFO’s).	The	BAND
switch	uses	feather-tauch pushbutton			switches.	A	tone
pulse	is heard whenever the switch is				pressed.

5-9 DIGITAL VFO

The TS-780 VFO is designed so that the pulses

generated by rotating the VFO knob								are counted	by the
microprocessor to vary the frequency								through PLL	circuit.
The		frequency	is varied step by Step. The step interval							is
20		Hz (SLOW)		for CW and SSB Operation or					200	Hz
(FAST) for fast-forward and FM							Operation. Either step can
be selected by the S/F switch							(sec section 5-12).
	The adjustable range of the digital VFO is shown									in
Table 1.
					F.STEP switch		“OFF”	F.STEP switch “ON”
	144 MHz BAND			1 4 4 , 0 0 0 . 0 0 -				1 4 4 , 0 0 0 . 0 0 -
				145,999.98				145.999.80		I
	430 MHz BAND			4 3 0 , 0 0 0 . 0 0 -				4 3 0 , 0 0 0 . 0 0 -
				439.999.98				439.999.80
						Table	1

Turning the VFO dial in either direction will shift the frequency in endless mode between 144 . 000 . 00 and 145.999.98 In the 144 MHz band. The dial also functions similarly in the 430 MHz band. Note that the upper limit of the band varies according to the Position (ON/OFF) of the F. STEP switch or mode.

15