Yaesu FT-712RH Manual

FT-712RH
TECHNICALSUPPLEMENT
YAESU MUSENCO.,LTD.
C.P.O.BOX 1500
TOKYO, JAPAN
MFlNURLCDISERV. X
rr-pia RH
05910739

This manualis intendedtoserve asa supplementto the FT-712RHOperatingManual.De-
tailedinformationregardingfunctions,specifications, options and operation has been provided
intheOperatingManual,and isnot reprinted herein. Therefore, this supplement is not
intendedto serve as anindependentreference,butto be used in conjunction withthe infor-
mationprovidedinthe OperatingManual.
Becauseofthe compactness andcomplexityof the double-sided glass-epoxy circuitboards
used in the FT-712RH,fourlayoutdiagramsare provided foreach board. Each side of the
boardisidentifiedby the typeof the majorityof components installed on thatside. In
most cases one side has onlychip components, and the other has either a mixtureof both
chipandleadcomponents(trimmers, coils, electrolytic capacitors, packaged ICs, etc.), or
lead components only.The two "obverse" views depict the board a?it isseen when viewed
directlywiththe eye, whilethe two "reverse" views depict the unseen side of the board as
itwould appear ifone were topeer through the board from the other side withoutseeing
the components and tracks on the near side.
Whilewe believethetechnicalinformationinthis manualiscorrect, Yaesu assumes no
liabilityfor damage thatmay occur asa resultof typographicalor other errorsthatmay be
present.Your cooperation in pointingoutany inconsistencies in the technical information
wouldbe appreciated.
Yaesu Musen reserves the rightto make changes in the circuitryof this transceiver, in the
interestof technological improvement, withoutnotificationof the owners.

BOTTOM COVERREMOVAL
Thefollowingcircuitboards are accessed
by removingthe bottom cover:
MainUnit* (component side)
IF Unit*
Mic Unit*
APC Unit
VCOUnit
PA Unit(lower edge only)
To removethebottomcover, remove the
fourscrews marked" * " in Figure1,plus
the fourmarked " ^ " ifthe top cover has
notalreadybeenremoved.Thenliftthe
cover away.
*Toaccessthese boards itmay be neces-
sarytoremovethloudspeakerand
holder:
(1)Referringto Figure 2, unplugthe
speakerwireconnector fromJ1005
ontheMainUnit,andliftthe
loudspeaker outof its bracket.
(2)Removethethreescrewsinthe
armsofthespeakerbracketand
remove the bracket.
TOP COVERREMOVAL
Removing the top cover exposes the Solder
Side of the Main Unitcircuit board and the
top edge of the PA Unitboard.
To remove the top cover, remove the four
screws marked " © " in Figure 1,plus the
fourmarked " 8$" if the bottom cover has
notalreadybeenremoved.Thenliftthe
cover away.
Figure2
FRONTPANELREMOVAL
Removingthe frontpanelallowsaccessto
theControlUnitandLCDUnitcircuit
boards.
(1)Afterthe top and bottom covers have
been removed, pulloffthe Selector, VOL
and SQL knobs.
(2)Removethenutfromthemicrophone
jackusinga slottedringwrenchas
shown in Figure 3.
The frontpanelcan now be slidforward.

PA UNIT
APC UNIT
430-VCO UNIT
LCD UNIT
CONTROL UNIT
BOARD LAYOUT
2

MAIN UNIT(No.1 XXX)
obverse view of "component" side
3
SOURCE
DRAIN
^GATE 2
Marked surface
3SK164(F)(01001)
3SK165(J)(01002)
M54959P(01013)
pPC7805H(01018)
L7809 (01017)
TDA2003(01008)

EMITTER
COLLECTOR
BASE
2SB1134R(Q1016)
COLLECTOR
EMITTER
BASE
2S02407(A)(Q1010)
BASE
COLLECTOR
EMITTER
2SD1000(LL) (Of007)
2SC3357(RK) (01009)
GATE
Marked Surface
2SK208Y (JY)(01014)
reverse view of "component" side
4

'COLLECTOR
Markedsurface.
2SA812(M7)(01005)
2SC1623(I_7)
(01004,1006,1015)
2SC2620(QB)(01003)
:2SC3356(R24)
(01011,1012)
MarkedSurface
1SS184(B3) (D1001)
HSM2693(B2)(D1005)
ANODEl/CATHODE2
1SS226(C3)(D1002)
obverse view of "chip-only" side
5

reverse view of "chip-only" side
- 6

MAIN UNITVOLTAGE CHART
(DCVOLTS)
MAIN UNIT1C VOLTAGE CHART (DCVOLTS)

IFUNIT(No.4 XX)
obverse view of "mixed-component" sideobverse view of "chip-only" side
reverse view of "mixed-component" sidereverse viewof"chip-only" side
Marked Surface
M5223FP(Q403)
2SC1623(L6)(Q402)
TK10487M(Q401)
IFUNITVOLTAGE CHART
(DCVOLTS)
9
^CATHODE
CATHODE
MarkedSuffice
1SS181(A3)(D402)
ANODE1/CATHODE2
-Y
Marked Surface
1SS226(03)(D401)

MICUNIT(No.5 XX)
obverse view of "1C"side obverse view of "chip-only" side
reverse view of "1C"sidereverse view of "chip-only" side
COLLECTOR
Marked Surface
2S01623(1-6)(0503)
FA1A4M-T2B(L33)
(0504-506)
MPD4052BG(Q502)
(DCVOLTS)
MICUNITVOLTAGE CHART
? S » % S is S» | » ll
s
^
- 10 -

(APCUnitPartLayout/CircuitDiagram)
APC UNIT(No.6 XX)
obverse view of "Tantalum CAP" side obverse view of "chip-only" side
reverse view of "Tantalum CAP" sidereverse view of "chip-only" side
CATHODE
COLLECTOR
B«««(Tr,;
Emitfr (Common) ^»<
s—crr,)^..'^,
^COLLECTOR(Tri)
''^COLLECTOR (Tr.)
ANOI
IODE ANODE
CATHOOE
CATHODE
MarkedSurfac*
FMS1(S1)(0601)
FMW1(W1)(0605)
Marked Surface
MarkedSurface
MarkedSurface.
2SB624(BV4) (0603,604)1SS184(B3)(D601)
2SC1623(L6)(0602)
FA1A4M-T2B(L33) (Q606)
1SS272(A1)(D602)
APC UNITVOLTAGE CHART
(DCVOLTS)
n

430-VCO UNIT(No.3 XX)
'•^^s^
^i^i'^
obverse view of "component" sideobverse view of "chip-only" side
reverse view of "component" side reverse view of "chip-only" side
Marked Surface
2SC3356(R24)(0301)
DRAIN
SOURCE
2SK125(0302)
VCO UNITVOLTAGE CHART
(DCVOLTS)
RESISTORVALUESAREIN0.1/tOW;
CAPACITORVALUESAREINfF. 50wv;
INDUCTORVALUESAREINH;
UNLESSOTHERWISENOTED.
12

CONTROL UNIT(No.2 XXX)
rCx^ia'agi!niw_- r^-^"
obverse view of "mixed-component" sidereverse view of "mixed-component" side
- 13 -

20""""""32
HD404418A01F(02003)
obverse view of "1C"side
14 -

'-: •" ~ •' <• ^ S
obverse view of "1C"side
15
ANODE 1/CATHOOE1

PA UNIT(No.7 XX)
obverse view of "component" side reverse view of "component" side
17

obverse view of "chip-only" side reverse view of "chip-only" side
18

19