Yaesu FT-712RH User manual

OPERATING
MANUAL
FT-712RH
Y
AESU MUSEN CO.,
LTD. C.P.O. BOX 1500
TOKYO, JAPAN

CONTENTS
SUPPLIED ACCESSORIES . . 2Memor
y
Stora
g
e21
Memory Recall 22
OPTIONS . . . . . . . . . . 2 Hiding/Erasing Memories 22
Call Channel Memory 23
SPECIFICATIONS . . . . . . 3Scanning 23
Memory Skip Scanning 24
CONTROLS & CONNECTORS 4 Programmable Memory
FRONT PANEL 4 Scanning (PMS) 24
REAR PANEL 7 Priority Monitoring 25
Tone Squelch Operation 26
INSTALLATION . . . . . . . 8
Antenna Considerations 8 DVS-1 DIGITAL VOICE
Mobile Installation 8 SYSTEM . . . . . . . . 27
Mobile Power Connections 10 Voice System Display 28
External Accessories 11 Segmentation Codes 30
Base Station Installation 12 Recording 30
Packet TNC Interconnections 12 On-The-Air Recording &
DVS-1 Digital Voice System Playback 32
Installation 13 Remote Station Recording
FTS-12 Tone Squelch Unit & Playback 32
Installation 15 Locking Segments 34
Memory Cloning 16 Private Station ID Code 35
Modification for Packet Radio 17
CAT System External Compu-
ter Control . . . . . . . 37
OPERATION . . . . . . . . 18
Preliminary Operating Infor
mation 18 In Case of Problems . . . . . 40
Squelch Setup 18
Frequency/Step Selection 19
Transmitting 20
Re
p
eater S
p
lits 20

YAESU FT-712RH COMPACT 70cm FM MOBILE
TRANSCEIVER
The FT-712RH is a compact, full-featured frequency synthesized FM mobile/base
transceiver providing selectable power output of either 3 or 35 watts on the 70cm
amateur band. Unique features include the optional DVS-1 Digital Voice System,
which provides local and remote digital voice recording and playback when
installed in the FT-712RH.
Inside the FT-712RH, surface-mount components provide high reliability and
performance, while modular circuit construction makes servicing easy. An all-
new compartmentalized die-cast chassis provides superb rf isolation and
incredible overall ruggedness. A large liquid crystal display includes a bargraph
PO/S-meter. Ambient light is sensed to automatically control the brightness of
the display back-lighting and pilot lamps, dimming the display in dark
environments.
Operating features include memory selection and tuning in 5, 10, 12.5, 15, 20 and
25 kHz selectable steps; The channel memory system includes 19 general purpose
memories, a one-touch recall CALL channel memory and two subband limit
memories (for programmable subband scanning); one-touch repeater reverse;
band and selected memory scanning with auto-resume after carrier-drop or 5-
second pause, and priority channel monitoring. Memory hiding and scan-skip are
easily settable.
Twenty of the memories store either programmable repeater shift or independent
transmit and receive frequencies. When the optional FTS-12 Tone Squelch unit is
installed, any of 37 standard CTCSS (subaudible) tone frequencies can be
displayed, selected and programmed into any memory channel for either silent
monitoring or encode-only operation.
The microphone jack includes signals for CAT System control from an external
personal computer, and memory cloning to/from other FT-712RHs. A 1750 Hz
burst tone generator is built-in and can be activated from the MH-14A8
Speaker/Mic. DTMF keypad microphone options include the MH-15C8 and the
MH-15D8 with its own auto-dial DTMF memories. If the burst tone is not
needed, an internal jumper can be set to allow packet radio tnc interfacing via the
microphone jack.
- 1 -

Along with one microphone, the MMB-37 Reversible Mobile Bracket is supplied
with the transceiver. For base station installations, the FP-700 AC Power
Supply/External Speaker is optionally available.
Please read this manual before installing or operating the FT-712RH.
SUPPLIED ACCESSORIES
MMB-37 Mobile Mounting Bracket 136000056
Power Supply Cable T9015615 with two 15A fuses, 2.8m One of the
microphones listed below.
OPTIONS
Model Order Code
DVS-1 Digital Voice Memory Unit 133000567
FTS-12 Tone Squelch Unit 133000488
SP-55 External Speaker
MH-14A8 Hand Speaker/Mic w/Burst Button 131000051
MH-14B8 Hand Speaker/Mic 131000052
MH-14138 Standard Hand Mic 131000067
MH-15C8 Hand Speaker/Mic w/DTMF keypad 131000060
MH-15138 Hand Mic w/DTMF Autodialler Memory 131000061
MF-1A3B Boom Microphone with flexible arm
YH-1 Headset (w/microphone)
SB-10 PTT Switch Unit for MF-1A3B or YH-l
MODEL CHART
Version Fre
q
. ran
g
e
(
MHz
)
R tr. Shifter*
(
MHz
)
A 430 - 450 ±5
B 430 - 440 ±7.6**
C 430 - 440 ±1.6**
X430 - 440 ±5
* Default - freely programmable by operator
** Burst tone activated by MH-14A8 Microphone.
-2-

SPECIFICATINS
GENERAL RECEIVER
Frequency range: Circuit type:
see Model Chart Double-conversion superhet
Channel steps Intermediate frequencies:
5/10/12.5/20/25 kHz 45 MHz & 455 kHz
Standard repeater shift: Sensitivity (for 12dB SINAD):
see Model Chart better than 0.18uV
Mode of emission: Image ratio:
G3E better than 65dB
Antenna impedance: Selectivity (-6/-60dB)
50 ohms, unbalanced 12/30 kHz
Supply voltage: Audio Output (for 5% THD):
13.8 VDC ±10%, neg. Ground at least 1.5W into 8 ohms
Supply current:
Transmit 35W: 10A TRANSMITTER
Receive: 500mA
Standby: 300mA RF output power (50 ohms):
3 watts and 35 watts
Operating temp. range:
-20 to +60 °C Modulation method:
Variable reactance
Frequency accuracy:
±5ppm (-5° to +50°C) Maximum deviation:
±5 kHz
Case size (WHD):
140 x 40 x 160mm Spurious emissions:
at least 60 dB below carrier
Weight:
Approx. 1.25 kg Microphone impedance:
2 kilohms
Specification subject to change without notice.
-3-

CONTROLS & CONNECTORS
FRONT PANEL
(1) Selector Knob
This 24-position detented rotary switch is used for tuning as well as a wide variety
of function selections. The DWN and UP keys on the microphone duplicate the
functions of this knob.
(2) Push Button Switches
These push buttons select the various operating features. One or more beeps will
sound if the resulting command is accepted (beep notes are shown on page 33). The
white labels above or to the right of the buttons indicate their primary functions,
while the blue labels below the buttons indicate alternate functions, activated by
pressing the F/WRITE button momentarily first, and then the other button within
five seconds.
For descriptive purposes in this manual, alternate button functions are referenced
by the blue label, with "[F]+" in front of it to remind you to press F/WRITE first.
For example, "[F)+BEEP" indicates that you should press the F/WRITE button
followed by the VOICE/BEEP button (within five seconds). All button functions
are described in detail in the "Operation" section, and summarized in the
Operator's Quick Reference Charts.
- 4 -

(3) Auto Dimmer Sensor
Behind the glass is a photosensor which detects the level of ambient light,
causing the display lamps to be automatically dimmed in the dark.
(4) VOL Control
This control adjust the volume of the receiver audio.
(5) SQL Control
This control sets the threshold level at which received signals (or noise) open the
squelch. For maximum squelch sensitivity set this control from counterclockwise
just to the point where noise is silenced (and the BUSY indicator on the display
is off) when the channel is clear.
(6) MIC Jack
This 8-pin jack accepts microphone input and scanning control from the
microphone and/or control signals from an external computer. Memory cloning
can be performed with another transceiver through this jack, and an internal
modification also allows packet radio tnc connection here. Pinout is shown on
the next page.
(7) POWER Switch
This two-position push button turns the transceiver on and off.
(8) LOW/LOCK Button
Normally, this button toggles between high and low transmitter power output.
When low power is selected, two low-pitched beeps sound, and "LOW" appears
at the lower right corner of the display. Two highpitched beeps sound when high
power is selected.
If the F/WRITE button is pressed just before pressing the LOW/LOCK button,
transmitter power is not changed, but rather low/high beeps sound, and "LOCK"
appears in reverse letters at the lower left corner of the display, indicating that
the selector knob and all other
- 5 -

buttons are now disabled. Pressing [F]+LOCK again sounds high/low beeps as
the lock condition is released.
(9) Display
The display segments are follows. The meaning of each is described elsewhere in
this manual
MIC Jack Pinout
- 6 -

REAR PANEL
(1) 13.8VDC Cable Pigtail
This is the power supply connection for the transceiver. Use the fused DC Cable
supplied with the transceiver to make connection between this pigtail and the car
battery or other DC power supply capable of at least 10 Amperes (continuous). Make
certain that the red lead connects to the positive side of the supply.
(2) EXT SP (External Speaker) Jack
This 2-contact mini phone jack accepts a 4- to 16-ohm external speaker such as the
Yaesu SP-3, SP-4 or SP-55. When a plug is inserted into this jack the internal
speaker is disabled.
(3) ANT (Antenna) Jack
Connect a 70cm antenna to this type-N socket using 50-ohm coaxial cable and a
type-N plug. Make sure the antenna is designed specifically for use at the operating
frequency.
-7-

INSTALLATION
Antenna Considerations
The FT-712RH is designed for use with an antenna having an impedance near 50
ohms at the operating frequency. For optimum performance use a high-quality,
carefully designed antenna. The antenna should be connected at all times when
power is on, to avoid damage that can otherwise result if transmission occurs
accidentally when no antenna is connected.
Another important consideration is the feedline. For optimum performance use
the shortest possible length of the best quality coaxial cable available, and be
sure to use a properly matching plug (type-N) for the jack on the transceiver.
Mobile Installation
The FT-712RH must only be installed in cars having a negative ground electrical
system. The transceiver should be located where the display, controls and
microphone are easily accessible, and should be securely affixed using the
supplied MMB-37 mobile mounting bracket. The transceiver may be installed in
any position without adversely affecting its performance, but it should not be
mounted near a heater vent or where it could interfere with safe operation of the
vehicle. Make sure that plenty of space is provided at the rear of the transceiver
so that air can flow freely around the heatsink. Refer to the diagrams on the
facing page for installation of the MMB-37.
(1) Using the mounting bracket as a template, locate the mounting holes after
determining the mounting location with sufficient clearance for the
transceiver. Use a 4.8mm (3/16") bit to drill the holes. Secure the bracket
with the supplied screws, washers and nuts (Figure 1).
(2) Screw the two mounting clips to the sides of the transceiver using the small
hex bolts and washers supplied (Figure 2).
-8-

To install the transceiver, position the transceiver in the bracket so that the clip
on the left side fits into the slot in the left side of the bracket e 31, then push
the right side of the transceiver upwards until it latches.
To remove the transceiver place your hand underneath it and pull the latch on
the right side of the bracket outward until the right side of the transceiver drops
free.
-9-

Mobile Power Connections
Before connecting the power cable the maximum battery charging voltage should be
checked to ensure that it remains below 15V when the engine is run fast. If more
than 15V, the voltage regulator of the car should be adjusted before connecting the
transceiver.
Power connections should be made directly to the automobile battery using the
supplied cable with 15A in-line fuses. Connection to the cigarette lighter or other
accessory circuit may cause the fuse to blow in that circuit. Connecting the supplied
DC power cable to the battery independently of the rest of the automobile electrical
system will minimize possible ignition noise pickup and excessive supply voltage
dro
p
durin
g
transmission, while allowin
g
o
p
eration with the i
g
nition off.
Do not connect any power to the transceiver except via the supplied fused cable, and
do not attempt to defeat or bypass the fuses - they are their to protect you and the
equipment.
Connect the RED lead of the power cable to the POSITIVE (+) battery
terminal, and the BLACK lead to the NEGATIVE (-) terminal. If it is necessary to
extend the power cable, use #14 AWG or larger insulated, stranded copper wire, and
in all cases use the minimum power cable length practicable to keep voltage drop
minimal.
WARNING
NEVER APPLY AC POWER TO THE REAR PANEL POWER JACK
OF THE TRANSCEIVER. NEVER CONNECT DC VOLTAGE OF
MORE THAN 15 VOLTS TO THE POWER JACK. ALWAYS RE-
PLACE FUSES WITH 15A RATING. FAILURE TO OBSERVE THESE
PRECAUTIONS WILL VOID THE WARRANTY.
- 10 -

External Accessories
The SP-3, SP-4 and SP-55 External Speakers are optional accessories which allow
the source of audio from the transceiver to be repositioned for optimum hearing.
Especially practical for the noisy mobile environment, each includes its own
swivel-type mounting bracket, and is available from your Yaesu dealer. Also
available to enhance safety and mobile operating convenience are the YH-I Headset
with miniature boom microphone, and the full size MF-1A3B boom microphone
with flexible arm (both of which use the SB-10 PTT switch).
- 11 -

Base Station Installation
A power supply capable of providing at least 10A continuously at 13.8VDC is
required for operation from the AC line, and an external speaker is recommended.
The FP-700 AC power supply is available from your Yaesu dealer for this purpose.
Use the fused DC power cable supplied with the transceiver for making power
connections, and connect the external speaker to the EXT SP jack on the rear panel.
Packet Radio TNC Interconnections
Most popular packet radio tncs can be connected to the MIC jack of the FT-712RH
as follows:
TNC Jack to Radio FT-712RH MIC Jack
Receiver Audio in pin 4 (8 ohms, de-emphasized)
Squelch Status in pin 5* (open=8V, closed=0V 1 mA)
PTT (gnd=tx) out pin 6
Transmit Audio out pin 8 (400 ohms, pre-emphasized)
Use shielded cable for the audio lines, and keep the interconnecting cable as short
as possible to avoid RF pickup.
* Requires modification as described on page 17.
- 12 -

DVS-I Digital Voice System Installation
The DVS-I is a digital voice recording and playback system which allows you to
record either through the microphone or the receiver, and to play back selected
recorded messages through the speaker or transmitter. Remote-controlled recording
and playback is also provided by a built-in DTMF decoder. See the special section at
the end of this manual for complete details.
(1) Disconnect the power cable at the rear of the transceiver, place the transceiver
upside-down on the workbench, and remove the four screws on the bottom
cover. Loosen the two screws on each side, and then remove the bottom cover
(Figure 1).
(2) Lift the loudspeaker out of its holder, and then remove the three screws in the
arms of the holder, and lift it out of the chassis (Figure 2).
-13-

(3) Connect the 8-pin plug from the DVS-I to 8-pin jack J2003 on the inside
of the front panel (the gray wire should be nearest the center). See Figure
3.
(4) Connect the 7-pin plug from the DVS-I to 7-pin jack J2004 on the inside
of the front panel (the brown wire should be nearest the center).
(5) Connect the 3-pin plug from the DVS-1 to jack J1003 in the right front
corner of the speaker compartment.
(6) Making sure that no wires are pinched, set the DVS-I in place, routing
the speaker wires out under the back of the DVS-I. Install the two
supplied screws through the tabs in the DVS-I: one in the left front
corner of the chassis, and one in the rear.
(7) Set the Voice Memory Backup switch in the left rear corner of the DVS-I
(Figure 4) to the ON position (toward the rear).
(8) If also installing the FTS-12, proceed to step 2 of the FTS-12 Installation.
Otherwise, do step 5 of the FTS
-
12 Installation.
- 14 -

FTS-12 Tone Squelch Unit Installation
The FTS-12 provides either encode-only or encode/decode operation with 37
front panel selectable subaudible CTCSS tones, and is available for all versions
FT-712RH, from your local Yaesu dealer. See the "Operation" section for
functional details.
(1) Perform steps 1 and 2 of the DVS-I Installation Procedure.
(2) Remove the jumper plug from jack J1004 in the front left corner of the
speaker compartment (Fig. 5).
(3) Locate the unconnected brown 10-pin connector at the front of the speaker
compartment. Align the small tab on one side of this connector with the hole
in one side of the jack on the FTS-12, and mate these connectors (Fig. 6).
(4) Press the FTS-12 into the clip on the speaker holder (Fig. 7). The output tone
level (VRI on the FTS-12) is adjusted at the factory for the proper deviation,
so no adjustment is needed.
(5) Replace the speaker holder and its three screws, and replace the speaker in
the holder. Then replace the bottom cover and its four screws, and retighten
the two screws on each side.
- 175 -

Figure 6. Figure 7.
Memory Cloning
All memory data stored in one transceiver can be moved to another by connecting
the MIC jacks together as indicated in the diagram below (cloning cable is NOT
available from Yaesu).
(1) Turn both transceivers off, and then press and hold the F/WRITE buttons
while turning the power switches on. The displays will be blinking.
(2) Press the REV button on the destination transceiver (the display will stop
blinking).
(3) Press the RPT button on the source transceiver. When the data transfer is
complete, the displays should return to normal. If "Err" is displayed, turn
both transceivers off and try again.
(4) Turn both transceivers off and remove the cloning cable.
-16-

Modification for Packet Radio
As supplied from the factory, pin 5 of the MIC jack is wired through solder bridge
jumper no. 16 on the Control Unit to allow tone burst activation via the BURST
button on the MH-14A8 microphone. For packet radio operation jumper 16 must be
removed, disabling BURST control, and jumper 15 installed to provide output of
the squelch BUSY line for packet radio tries.
(1) Remove the eight screws affixing the top and bottom covers, and the two
screws on each side. Remove the covers.
(2) Remove the ring nut and lockwasher around the MIC jack, and pull the
three knobs from the front panel.
(3) Without unclipping the plastic cover, grasp the front panel on the top and
bottom edges, and carefully slide it forward just enough to expose the
corner of the Control Unit pcb nearest the MIC jack.
(4) Using a fine-tipped soldering iron and solder wick or a solder sucker,
remove the solder bridge from BURST jumper pad 16, and then add
solder to bridge BUSY pad 15.
(5) Press the front panel assembly gently back into place (so that the holes in
each side are aligned with those in the chassis). Replace the ring nut and
washer over the MIC jack, and the knobs. Replace the top and bottom
covers and their eight screws, and the four screws in the sides.
17

OPERATION
This chapter describes the various transceiver functions in detail. After studying
these descriptions, keep the FT-712RH Operator's Quick Reference Charts handy
in case you need to refresh your memory.
Preliminary Operating Information
Before operating the transceiver, recheck power supply and antenna connections.
Never operate the transceiver without an antenna. Also, please read the chapter on
Controls & Connectors, if you have not already, to familiarize yourself with the
functions of the controls. Note especially the description on page 4 of the
terminology used in this chapter when referring to the buttons.
When the buttons are pressed during reception, one or more beeps will sound if the
command is accepted. Except for certain special cases mentioned later, the buttons
are disabled during transmission.
If you have trouble getting the transceiver to work as described, see 'In Case of
Problems' on page 40.
Squelch Setup
Before turning on the transceiver for the first time, set the VOL and SQL controls
fully counterclockwise. Now press the POWER button and adjust the VOL control
for a_ comfortable volume on the noise or received signal. "BUSY" should be
displayed in reverse letters to the left of the S&PO meter scale. If a signal is
present, rotate the selector knob until a frequency is found where only noise is
heard.
Turn the SQL knob clockwise just to the point where the noise is silenced and
"BUSY" disappears (if the SQL is set further clockwise, sensitivity to weak signals
is reduced). Whenever a signal reaches the receiver that is strong enough to open
the squelch, "BUSY" will be displayed.
Bargraph segments appear in the S&PO box below the frequency on the display
while receiving, indicating received signal strength. This indication
- 18 -