Yaesu FT-902DM User manual

INSTRUCTION
MANUAL
FT-902DM
YAESU MUSEN CO., LTD.
TOKYO JAPAN

ALL MODE HF TRANSCEIVER
FT-902DM
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GENERAL DESCRIPTION
The FY-902DM is a precision engineered, high per-
formance HF transceiver of advanced design, pro-
viding all band coverage (160, 80.40, 30. 20, 17,
15, |2,and |]Ometers) on all modes of operation:
LSB, USB, CW, FSK, AM, and FM. This trans-
ceiver operates alan input power of 180 watts
on SSB/CW and 80 watts on AM, FM, and FSK.
Advanced features include PLL (Phase Locked
Loop) frequency derivation, digital plus. analog
frequency readout with large displuy LED digits,
a built-in Curtis 8044 IC electronic keyer, and
memory frequency control circuilry. Staite-of-the-
art receiver performance features Include rejection
tuning,
dualfilter
variable
IF
bandwidth
tuning,
and,
for
CW,
audio
peak
frequency
(APF)
tuning
for
unsurpassed
rejection
of
unwanted
signals.
Other
built-in
features
include
VOX,
semi-break-
in
CW
with
sidetone,
25
kHz
calibrator,
advanced
noise
blanker,
RF
speech
processor.
and
a
20
dB
RE
attenuator
for
protection
against
receiver
overload,
All
circuits,
except
the
transmilter
driver
and
final
amplifier
stages,
are
solid
state,
utilizing
modern
plug-in
printed
circuit
boards,
thus
per-
mitting
easy
maintenance.
The FT-902DM transceiver is entirely self-con-
lained, requiring only an antenna and power source
for operation. For base station operation, AC
power voltages of LOO/110/117/200/220/234 VAC
may be chosen, though the unit normally is sup-
plied with 117 volt capability. A DC-DC converter
unil provides fer mobile or portable operation.
Selection of AC or DC power source is automati-
cally made when the proper line cord is inserted.
For mobile operation a separate switch is provided
on the front panel to turn olf the tube heaters
while in the receive mode. With the heaters off,
current consumption is only 1.1 amp.
Among the available options on economy models
FT-902D/SD/DE are the memory unit, the keyer
unit, the DC-DC converter, the FM unil, and the
cooling fan. Optional equipment on all modets are
the 600 [lz CW filter and the 6 KHz AM filter.
The entire PT-902DM transceiver weighs approxi-
mately 18 kg., and is 342 mm wide, 154 mm high,
and 324 mm deep. A diecast front panel and
heavy-duty case provide maximum protection
against damage from shock and vibration during
travel use.

SPECIFICATIONS ©
GENERAL
Frequency coverage:
160m 1.8 - 2.0 MHz
80m 3.5 - 4.0 MHz
40m 7.0- 7.5 MHz
30m 10.0 - 10.5 MHz
20m 14.0 - 14.5 MHz
17m 18.0 - 18.5 MHz
15m 21.0 - 21.5 MHz
12m 24.5 - 25.0 MHz
10mA 28.5 - 28.5 MHz
10mB 28.5 - 29.0 MHz
10mC 29.0 - 29.5 MHz
10mD 29.5 - 29.9 MHz
Power requirements:
AC 100/110/117/200/220/234 V, 50/60 Hz
DC 13.5 V, negative ground
(DC option FT-902D/SD/DE)
Power consumption:
(FT-902DM/D/DE)
AC 117 V: 70 watts receive
(45 watts HEATER OFF)
320 watts transmit (max)
DC 13.5 V: 5A receive
(1.1 A HEATER OFF)
21 A transmit (max)
(FT-902SD)
AC 117V: 55 watts-receive
(45 watts HEATER OFF)
105 watts transmit (max)
DC 13.5 V: 3.8 A receive
(0.8 A HEATER OFF)
7.5 A transmit (max)
Size:
342 (W) x 154 (H) x 324 (D) mm
Weight:
I8kg
TRANSMITTER
Emission:
LSB, USB (A3j), CW (Al), AM (A3h), FM
(F3) (option FT-902SD/DE), FSK (F1)
PA input power:
FT-902DM/D/DE
SSB/CW: 180 watts DC
AM/FSK/FM: 80 watts DC
FT-902SD
SSB/CW/FSK/FM: 20 watts DC
AM: 5 watts DC :
Carrier suppression:
Better than 40 dB
Unwanted sideband suppression:
Better than 40 dB @ 1000 Hz
Spurious radiation:
Better than 40 dB below rated output
Transmitter frequency response:
300 - 2700 Hz (6 dB)
Third order distortion products:
Better than 31 dB below rated output
Transmitter frequency stability:
Less
than
300
Hz
after
10
minute
warmup:
less than 100 Hz after 30 minute warmup.
Negative feedback:
6 dB at 14 MHz
Modulation:
A3J: Balanced modulator
A3h: Amplitude modulation of a low power
stage
F3: Variable-reactance frequency modula-
tion, max. deviation +5 kHz (F3 fea-
ture optional on FT-902SD/DE)
Antenna output impedance:
50-75 Ohms, unbalanced
Microphone input impedance:
500 - 600 Ohms

RECEIVER Passband tuning:
Continuous from 2.4 kHz to 300 Hz
Sensitivity:
SSB/CW/FSK 0.25 pV for S/N 10 dB Intermodulation:
AM 1 uv for S/N 10 dB Better than 80 dB immunity at 20 kHz offset
FM 0.3 uV for 20 dB quieting 20 dB inputs at 14 MHz
Image rejection: Desensitization:
1.8- 25 MHz - - Better than 60 dB Better than 100 dB immunity at 20 kHz off
28 MHz - - Better than 50 dB 20 dB input at 14 MHz
IF
rejection:
APF
response:
Better than 70 dB Within 3 dB from 400 - 900 Hz
Selectivity, WIDTH control at “0” Audio output:
SSB: -6 dB/2.4kHz —60 dB/4.0 kHz Better than 3 watts @ 10% THD
*CW: -—6dB/0.6kHz —60dB/1.2 kHz
*AM: —6dB/6.0kHz -—60 dB/12.0 kHz Audio output impedance:
**FM: —6 dB/12.0 kHz —60 dB/24.0 kHz ALAS Ohms
*AM and CW filters are optional, all models
**FM UNIT optional on FT-902SD/DE
FT-902D/SD/DE/DM MODEL DIFFERENCES
O = Built-in feature X = Available option
FEATURE " FT-9020 | FT-902SD | FT-902DE ' FT-902DM —
BANDCRYSTAL 160m OO O See ae Oe.
BAND CRYSTAL 80m ss O om cm oO
| BAND CRYSTAL 40m | fe) O eo if oO
BAND CRYSTAL 30m | eee OT ee 2
“BAND CRYSTAL 20m G2. oO | O Oo.
BAND CRYSTAL 17m Oo | om 30 ic)
-BANDCRYSTAL 15m =| O..— O Ge. | Onc!
BAND CRYSTAL 12m | Or. fon it ee Oo.
| BAND CRYSTAL —-10mA__ O O oO oan
BAND CRYSTAL 10mB leg Orch — JO o. -|. =-6
_BAND CRYSTAL __10mC “Or, = lit OL I Or). - Oe
BAND CRYSTAL —_10mD io “© O 0
-VOX/MARKER UNIT 0 O on O-
FM UNIT as em al oa a ae % O. |
_RF SPEECH PROCESSOR _ oO O sue), i Os
AM FILTER 7 x x x XP
CW FILTER | —, x Ne x 4
FM FILTER = x . a a x
_KEYER UNIT ; | x -. or eas)
MEMORY UNIT ; | x x = oe ee Cs
_DC-DC CONVERTER - | x x x O
COOLING FAN o |... & ec or |i
_POWER OUTPUT = = =—S |s~Ss«100 W 10W- 100 W 100 W

TUBE COMPLEMENT
12BY7A 1
6146B 2
SEMICONDUCTOR
COMPLEMENT
Germanium Transistor:
T20A6 2
Silicon Transistor :
2SA496Y 2
2SA564A-R 2
2SA639 1
28A733 3
2SA952L 13
28C372Y 4
2SC380TM-Y 15
2SC535A 1
2SC732TM 5
2SC735Y 3
2SC785-O 3
2SC1674L 1
2SC1815Y 29
2SC1815GR 11
2S8C2407 2
MPSA13 1
FET:
2SK19GR 11
2SK19TM-BL 10
2SK34E 1
3SK40M 3
3SK51-03 9
3SK59Y 1
3SK59GR 1
3SK73 1
JF1033B 4
J310 1
Ic:
MC3403P
MC14011BCP
MC14042BCP
MC4044P
(uPC1008C)
TA7205AP 1
TA7063P 2
TA7061AP 2
TA7310P |
TA7089M 1
TA7060P 1
I
2
3
1
1
]
NON
TC503 2P
uPC14305
uPC14308
uPC14312
uPAS4H
SN75450B
Specifications subject to change without notice.
SN74LS192N
SN74LSO0ON
SN74LS04N
SN74LS123N
MSM5562
MSM9520RS
MM74C90N
NJM78LOS5A
NJM78L08
LM308
8044
34024PCQM
Germanium Diode:
1N60
1S188FM
181007
Silicon Diode:
181555
1SS53
10D1
10D10
VO6B
SM1-12
— i OND Ss RE OND SO
12
6
30
101
ee WN wo ON
Varactor Diode:
182209 2
182236 ]
FC63 ]
MV104 12
Zener Diode:
WZ050 2
WZ060 1
WZ090 5
WZ110 2
Schottky Barrier Diode:
ND487C2 1
LED:
GD4-203SRD 12
LED Display:
HP5082-7623 6

CONTROLS AND SWITCHES
This transceiver has been specifically designed for
ease of operation and versatility. The operator
may, however. be unfamiliar with the operation
of the controls, and improper adjustment thereof
may result in poor transceiver performance. Thus,
be certain that you understand the function of
every control before operating the transceiver,
The various front panel controls and switches
are described in the following section,
/
(1) MODE
The MODE switch has six positions for selection
of the operating mode desired! LSB, USB, CW.
FSK, AM, or FM.
(2) REJECT-WIDTH
The REJECT und WIDTH controls are mounted
on concentric shafts: The rejection tuning control
(REJECT). when activated by pressing the small
the left of the REJECT
knob, provides u variable IF notch filter action
for nulling Oul a particular interfering signal,
silver pushbutton. to
The WIDTH control varies the signal across the
passband of one of the two IF 8-pole crystal band-
pass filters used in this circuit. thus providing a
variable IF bandwidth for rejection of signals above
or below the desired signal,
(3) M
The M button is pressed to store a frequency in
the memory circuitry. Whatever lrequency is
being read out on the digital display will be the
lrequency stored when the M button is pushed.
mA
* Tololeloioroy
mes AH) SEES FOG
(4) EXT
When pushed, the EXT button transfers frequency
control from the FT-902DM to an external VFO,
such as the FV-901DM fully synthesized scanning
VFO.
(5) VEO
When the VFO button is pushed, frequeney con-
trol is transfered from EXT or memory control to
the FT-902DM internal VFO,
(6) TX-MR-RX
Once a frequency has been stored by the memory
(M) button, that frequency may be recalled for
control of either the transmit or reeeive frequency
by pushing either the TX or RX MR _ button,
respectively,
(7) MR
Once a frequency has been stored by the memory
(M) button, that frequency may be recalled for
control of the transceive frequency by pushing
the MR button.

(8) PRESELECT
This control pretunes the signal circuits for both
transmit and receive. The PRESELECT circuit
provides continuous permeability tuning through-
out the frequency range of the transceiver.
(9) BAND
The BAND switch provides selection of the band
desired, 160 through 10 meters.
(10) RF GAIN/CLARIFIER
The RE GAIN and CLARIFIER controls are
mounted on concentric shafts. The RF GAIN
control provides manual control of the gain levels
of the RF and IF amplifiers on receive.
The CLARIFIER control allows manual offset of
42.5 kHz of either the transmit or receive fre-
quency. Selection of transmit or receive clarifier
is made hy the two silver pushbuttons to the
left of the CLARIFIER control.
(11) ATT
The ATT (RF attenuator) button provides inser-
tion of a 20 dB attenuator in the incoming signal
path to minimize receiver cross modulation caused
by extremely strong local signals.
(12) PROC LEVEL/AF GAIN
The PROC LEVEL and AF GAIN controls are
mounted on concentric shafts. The PROC LEVEL
control allows manual control of the output level
of the RF speech processor. The processor is
actuated by pressing the silver pushbutton to the
left of the PROC LEVEL control.
The AF GAIN control adjusts the audio output
level at the speaker and phone jack. Clockwise
rotation increases the audio output.
(13) TUNE
This pushbutton, when depressed, places the trans-
mitter in the “tune” condition for ten seconds
for tuning purposes. After ten seconds, the trans-
ceiver is returned to the receive mode so as to
prevent damage to the final amplifier tubes caused
by excessive “key down” time during tune-up.
(14) LOADING
This control tunes the output circuit of the pi net-
work to match the antenna/feedline impedance.
(15) PLATE
This control tunes the plate circuit of the final
amplifier.
(16) DIM
This control allows dimming of the meter and dial
lamps.
(17) CARR/KEYER
The CARR and KEYER controls are mounted
on concentric shafts. The CARR control varies
the amount of carrier in the CW, AM, FSK, and
FM models of operation.
The KEYER control varies the speed of the
built-in Curtis 8044 IC electronic keyer.
(18) VOX GAIN
This control selects MOX/PTT/VOX transmitter
relay control as well as adjusting the sensitivity of
the VOX circuitry. The PTT position provides
push-to-talk operation from a microphone PTT
switch or a footswitch. The MOX position provides
manual transmit. It must be returned to the PTT
position for receiver recovery.
(19) APF FREQ
This knob, when actuated by turning on the APF
switch, provides manual control for peaking the
audio peak filter (APF) circuit on the desired
signal. This control will find its chief usefulness
on CW, because its bandwidth is much too narrow
for normal SSB reception.
(20) SQL/MIC GAIN
The SQL and MIC GAIN controls are mounted on
concentric shafts. The SQL control sets the squelch
threshold level for FM reception.
The MIC GAIN control varies the audio level from
the microphone amplifier stage. The control has
sufficient range to permit the use of any low im-
pedance (500 - 600 Ohm) crystal or dynamic
microphone. Clockwise rotation increases the level
of output from the microphone amplifier stage.
(21) FUNCTION SWITCHES: AMGC, APF/MONI,
AGC, PO/IC/ALC, and NB/MARK
The AMGC switch activates a microphone gain
threshold circuit which requires a_ particular

minimum input level from the microphone to
trigger the microphone amplifier. Low-level back-
ground noise will not activate the transmitter
with the AMGC in operation. This circuit may be
considered a ‘“‘microphone squelch” system. The
M GAIN control functions normally with the
AMGC system in operation.
When the APF/MONI switch is in the APF posi-
tion, the audio peak filter (APF) circuitry
is activated. The exact frequency of the audio
peak is set by the APF FREQ knob. When this
switch is placed in the MONI position, monitor-
ing of the microphone level may be accomplished
for operator convenience or tape recording both
sides of a QSO. In the CW mode, CW sidetone
will be heard regardless of the position of the
APF/MONI switch.
The AGC switch controls the length of the re-
covery time for the receiver AGC circuitry. This
switch provides slow or fast recovery, and will
also turn off the AGC if desired.
The PO/IC/ALC switch will hereafter be referred
to as the METER switch. In the PO position,
relative transmitter output power can be observed.
In the IC position, transmitter final amplifier
cathode current may be measured. In the ALC
position, transmitter ALC voltage may be read.
When the FT-902DM is in the receive mode, the
meter functions as an “‘S”’ meter.
The NB/MARK switch provides for actuation of
either the Noise Blanker (NB) or crystal calibrator
(MARK). The marker oscillator can produce cali-
bration signals at intervals of either 25 kHz or
100 kHz by proper positioning of a switch inside
the cabinet.
(22) POWER
This is the main on/off switch for the transceiver.
In the OFF position, the memory circuits are
disabled, so that when the transceiver is turned to
ON again, the memory circuits will have to be
reset.
(23) HEATER
With the HEATER switch in the down position,
the transmitter tube heaters are turned off. This
reduces battery drain to 1.1 amp and thus permits
long periods of listening without excessive battery
drain. Placing this switch in the up position pro-
vides supply voltage to the tube heaters, and
after 30 seconds of warmup the transmitter is
ready for operation. This switch operates in both
the AC and DC modes.
(24) PHONES
This is a standard 1/4” phone jack for accom-
modation of headphones. The internal speaker is
disabled when headphones are plugged into this
jack.
(25) MIC
This four-conductor jack accommodates the
microphone plug for microphone input as well as
for PTT actuation.
MIC
Mic plug
Headphone plug

REAR
APRON
CONNECTIONS
(1) GND
Threaded lug for ground connection.
(2) RF OUT
Signal frequency output from the driver stage
may be obtained at this jack for use with optional
equipment, such as the FTY-90O1R transverter.
(3) ANT
Coaxial conneclion for antenna.
(4) PO ADJ
Sets PO meter sensitivity.
(S) RCV ANT
A second receiver receives its antenna connection
through this jack,
(6) ACC
Accessory socket. Provides access to transceiver
operating voltages and relay contacts.
(7) KEY
Three-conductor jack for connection to keyer
paddle or external key,
(8) EXT VFO
Connections for external VFO.
ral
(9) FUSE
Fuse holder requires 5 amp fuse for 117 volt or
3 amp fuse for 220 volt operation, For 12 volt
DC operation, a 20 amp fuse ts installed in the
power cable, When replacing fuses, be certain to
install a fuse of the proper rating. The
caused by improper fuse
warranty
does not cover damage
replacement.
(10) POWER
Power receptacie. Both AC and DC cables are
supplied.
(11) TONE
Sidetone output for second receiver (if used).
(12) IF OUT 2
Wide-bandwidth 8.9 MHz IP signal for connection
to a spectrum analyzer, ete,
(13) PATCH
Speech input terminal for phone patch connection.
Impedance is 500 ohms,
(14) A-TRIP
Anti-trip input from second receiver (if used).
(15) SP
Audio output is provided at this jack for an ex-
ternal speaker. Outpul impedance ts 4 ohms, and

the internal speaker will be disabled when plug
is inserted.
(16) PTT
This jack may be used for external actuation of
the transmitter. As an example, a footswitch may
be connected to this jack to provide remote con- PIN No.
; ; 1 HEATER
trol of the transmitter relay, leaving the operator’s 2 HEATER
hands free for writing and tuning purposes. 4 +300V
5 +800V
6 —100V
7 ALC
(17)
FSK
9
TX
GND
.
10
RX
GND
Input from the FSK terminal may be made WNC
through this jack. The FT-902DM is set up for
1
170 Hz shift. eens
(18) IF OUT 1
Narrow bandwidth 8.9 MHz IF output is avail- KN
able for use with an IF monitorscope, etc. PExTIN
3 EXT OV
(19) REMOTE 4 AGC OUT
5 TX12V
6 GND
Provides switched 13.5 VDC for relay control
for external low-pass filter units, etc. As the band- EXT VFO PLUG
switch is rotated, 13.5 VDC will appear at various
pins on the REMOTE jack. Use a VOM to deter-
mine the proper pin for the band in use. — i
HU et
S>
oot neeney
MMON © q
AO he Ss ‘3 i+
Se )
Ma
ML
Pin plug
Cooling fan |
External
speaker
,
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