DRAKE FS-4 User manual

€m MODEL
FS-4
v FRRE@,uEIvc.Y
SYA'THEg'IZEtrI

t-
LIMITEDWARRANTY
R. L. DRAKE COMPANY warmnts to the orígínal purchaser that thís product
shall befree from defects ín materíal (except tubes and RF output transistors)
or workmanshipfor ninety (90) daysfrom the date of original purchase.
During the wanonty period the R-L. DRAKE COMPANY or an authorized
Drake servicefacility will provide ftee of choge both ports (except tubes and
RF output fiansistors) and l¿bor neces$lry to correct defects in material or
workmanship.
To obtain suchwananty semíce,the original purchasermust:
(
I) Completeand sendin the tilananty Registration Card.
(2) Notify R. L. DRAKE COMPANY or its nearestauthorized service
facility,
assoonas
possibleafter discovery of apossibledefect, of:
(a) Themodel numberand serialnumber, if any;
(b) The identity of the seller and the approxinute date of purchase;
(c) A detail¿d description of theproblem, including details on the elecffí'
calconnection
to associated
equipmentandthelist of such equipment.
(3) Deliver the product to theR.L. DRAKE COMPANY
or thenearest
author-
ized service
facility, or ship the samein its original container or equívalent,
fully ínsureda¡tdshipping chmges
prepatd.
Conect maintenance,"repair
ond useare important to obtain proper perform'
ance from this product. Thoefore, carefully read the Instruction Manual. This
warranty does not apply to any defect that R. L. DRAKE COMPANY deter-
minesisdueto:
(1) Improper maintenance or repair, includíng the installation of parts or
accessories
that do not conform to the quality and speciftcations of the
original parts.
(2) Misuse,
abuse,neglector improper installation.
(3) Accidental or íntentional damage.
All ímplied warranties,
if any, terminateninety (90) days
fiom the dateof the
originalpurchase.
The foregoing constítutesR. L, DRAKE COMPANY'S entire obligation with
respect to this product, and the oríginal purchaserand any user or owner shall
haveno other remedy and no claím for incidental or consequentialdamages'
Some statesdo not allow limitations on how long an implied warranty lastsor
do not allow theexclusion
or limitation of íncidental
or consequential
damages,
sotheabove
limitatíon andexclusionm0ynot apply to you.
This wananty gives specific legal rights and you may also haveother rights
which varyfrom state to state.
R. L. DRAKE COMPAI{Y
540 Rich¡rd Street o Miamisburg,Ohio45342
PRINTED IN U.S.A.

YCHAPTERI
INTRODUCTION
1.1.GENERALDESCRIPTION,
The FS4 is a frequency synthesizerdevelopedfor usewith the Drake
Company "4" line equipment. (R4 series,T-4X seriesand SPR4.) The
FS-4 plugs into an unused auxiliary crystal socket in the rear of the
receiver
or transmitter, and will supply the variousinjection signalsto the
eguipment and allowscontinuous coverage
without utilizing the accessory
crystals.
The frequency readout on the FS4 displaysthe receivedfrequencyband,
andto thisis addedthe frequencyreadoutofthe receiver
"PTO" to obtain
the correctreceived
frequency.
The FS4 suppliesall the crystal oscillator injection signalsfor the R4
series
and T4X seriesin 0.5MHz stepsfrom 11.1
through40.6MHz,and
the readout is ürect. An accessorykit is availableto provide proper
injection signalsfor the SPR4 receiver.
The FS4 canbe usedwith the 21 type receiver
overthe frequencyrange
of 7 to 30 MHz. Whenusedwith the 24, receiver,
the FS-4frequencyread-
out isnot direct,andacorrection factor of "7 MHz" must beaddedto the
FS-4 readout to obtain the correct operatingfrequency.A special
acces-
sorykit isnecessaryto modify the FS4 for usewith the 2-Creceiver.
1.2.MANUAL
COVERAGE.
This manual is presented
in 5 chaptersandisarrangedfor the convenience
ofthe operatorandservicetechnicianasfollows:
CHAPTERI Introduction.
(Self
explanatory.)
CHAPTERII Installation. Describesthe procedures
to befollowed prior
to operation.
a
JANUARY
1977

CHAPTER
III
CHAPTER
IV
CHAPTER
V
Operaüon.
Illustrates
anddescribes
front panel
controls,
and describes
operation
with Drakereceiver/transmitter
equipment.
Theory
of Operation.
Describes
all circuitsand
networks.
Maintenance.Provides niaintenanceand alignment
instructions.
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Y
CHAPTER
II
INSTALLATION
2.1.UNPACK¡NG.
Carefully
removethe FS4 from the shippingcartonandexamine
it for
evidence
of damage.
If anydamageisdiscovered,
immediatelynotify the
transportationcompany
thatdelivered
theunit.
NOTE
Fill out the enclosed
registrationcard and return it to
the factory immediately to insure registration and
validation of the warranty.
2-2. LOCATION.
The FS4 issupplied
with a cable
approximately
20incheslong
that plugs
into the accessory
crystalsocketof the receiver/transmitter.
Thislength
allowsthe user
to place theFS-4on either
sideof thereceiver/transmitter.
Placingthe FS4 on top of the transmitteris not recommended,dueto
heatgenerated
within thetransmitter,
andtheFS4 will blocktheairflow.
2.3. POWER
REOUIREMENTS.
The FS4 is shippedfrom the factory wired for 120 VAC, 50160
Hz,
operationunless
otherwise
specified.
To operateon 240VAC makethe
properconnections at thetransfornerontheparent
board
asillustrated
in
figure
2-1.
24. FUSE.
Thepowerlineisfused
for 120
VAC operation
with a 3AG Typel/84,
Slo-Blo.
For 24OVAC operationuse
a3AGType1l16A, orequivalent.

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CHAPTERIII
OPERATION
3.1.CONTROLSANDDISPLAYS.
All controlsand displaysnecessaryfor the operationof the FS4 are
locatedon thefront panel. The
th¡eeknobsswitch
thefrequencyrangein
.5MHzstepsand
provide
direct
frequency
displayin MHzatthereadout
directlyabove eachknob.These
knobs
switchthefrequencyin steps
of
l0 MHz,I MHz,
and
0.5MHz
fromleft to right.The0.5 MHzknob
also
turnstheFS-4 onandoff. Referto figure3-1.
3.2.INJECTION
CABLE.
The injectioncable supplied
is usedto connect the FS4 to anunused
accessorycrystalsocket
of thereceiveror transmitter.Attachthe
ground
lugto thechassis
at theaccessorycrystal
socket
and
insert
thecenter
pin
into theselectedaccessory
crystal
socket.
Thereceiver ortransmitterwlll
operatebestwhen
the
center
conductorisconnectedtothe emitter
ofthe
crystaloscillator.
Thiscanbedetermined
bynotingtheS
meter
reading
or
power
outputreadoutwhen
theinjectioncable
isplugged intoeach socket
oftheaccessorycrystal
socket.
3.3.BANDSELECT.
Whenusingthe FS-4to controla receiveror transmitter,
the receiver/
transmittermustbe
placed
inthe
proper
bandas
youwould
innormal use,
andthecrystal
switchmust
beplaced in theposition corresponding
with
theposition selected
to plug intheFS-4.TheRFtune
(preselector)
ofthe
receiver/transmittermust
betuned
thesameas
innormal
use.
34. PRESELECTOR
SETTING.
A stick-on-decal has been supplied for convenience in loca*ing
positioning of the RF tune (preselector).
This may be applied to
receiver/transmitter front panel by removing the knob and aligning
decalon the front panel
andfirmly rubbingit on.
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cautionmustbe used
on proper
use
of theFS4 when
used
with trans-
mitters.
consult RF Tunecalibration
chartsin the manual
of theT-4x
series.
3.5.
TUNING
A RECEIVER
AND
THE
FS4.
a. Switch
theFS-4
to thedesired
operating
frequency,
asan
example:
7.0
for40meter
amateur
band.
b. Place
theR-4Receiver
"Xtals" switch
in position
l0 (assuming
the
FS-4
isplugged
intoaccessory
crystal
socket
+10).
c. Setthe
R4 "Band"
switch
to 2.0.
d. Set
"PRESELECTOR"
control
between
5and
6.
The
FS-4
and
receiver
are
now
correctly
set
forproper
operation.
The
rest
of theoperatingprocedure
is
called
out
inthereceiver/transmitter
instruc-
tion
manual.
3-6. MODIFICATION
OFTHE
FS-4
FOR
USE
W|TH
THE
SpR-4
or 2-C.
The FS4 canbemodified
fromthestandard
version
to operateproperly
with the SPR-4
or 21 by simplyremoving
the caseof the FS4 and
exchanging
thereference
crystalasshown
in figure
5-1,
and
substituting
the interconnecting
cablewith onethat has
aplugwhich
fits theSpR-4
accessory
socket.
Drill a ll4" üa.holein therearpanel
of theSpR-4
or
21, and
insert
grommet.
Feed
theFS4 injection
cable
through
thishole
toan
unused
crystal
socket.
Thecorrect
reference
frequency
crystal
for theequipment
isshown
in the
chart
below:
Controlled
Equipment FS-4
Reference
Crystal
R4 and
T4X
SPR4
24,
*7 MHz must be added to
frequency.
9.6MHz
9.59-
9.5*
the FS-4 readout for proper operating
7

The FS4 should be unplugged
from the receiver
or transmitter if opera-
tion is desiredfrom internal crystal control and not by useof the FS4.
The cable capacity of the FS4 can causeoscillation of the receiveror
transmitter that isnot controlled by the selected
crystal.
NOTE
No tuning of L406 is required when exchangingthe
referencecrystal for "qse
with the SPR4. Someadjust-
ment may be requiredwhen exchanging
the crystal for
use with the 21. See paragraph 5-3, for the proper
tuning procedure.
when using the FS4 to control the frequency of the 21 the vFo dial
alwaysreads
on the black scale.
The red scale
doesnot apply whenusing
the
FS4.
3.7. FREOUENCY
ACCURACY.
All injection frequencies
in the Fs4 arederived
from the 5MHz clock and
the réference oscillator. Any frequency error in the injection signalis
essentiallythe sameat any frequency band.when derivingthe injection
frequency by useof crystalsin the crystal oscillator in the receiver,
asis
normally done, the frequency error will vary from bandto bandasdiffer-
ent crystalsare switchedin. This error is compensated
for when thePTO
iscalibrated.
A differencein frequencymay benoted when switchingbetween
standard
operate
andFS-4operate.
This error isdueto crystalerrorsasstated
above
and in generalthe use
of the FS4 results
in the better frequencyaccuracy.
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