Ferrograph 702 Mk2 Service Manual

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series seven

L OPERATORS HANDBOOK

FEHROGRAPH

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MID-ODD. ISSUE 4

OPERATOR'S HANDBOOK

Farragmph

SERIES SEVEN. MK 2

SEFIIAL NUMBER 78.800/2 ONWAHDB

THE FERROGRAPH COMPANY LID.
IONDON AND SOUTH SHIELDS

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GENERAL DESCRIPTION

The Series Seven Ferrogiaphs retain the basrc 3 motor drive system of
the earlier models. but have completely redesrgned mechanics with
solenord operation. This enables the tape to be started and stopped by
remote swttching. and on Record and Replay the recorder can be
controlled by a time swrtch.

The main lunctrons ol the deck (Fast. Stop, Pause, Run) are selected
by a Single knob, With a separate press button lor Record. On last mod
the direction and speed of wrnd are flavoured try a separate control.
An automatic stop operates at the end 0! the reel and the 4-drgrt turns
counter is driven lrom the teke»up spool.

Reel retainers are fitted to the reel carriers. which wrll accommodate
all types of spool oonlormrng to the International standard Three tape
speeds are available on each deck. and tension arms provide slur-free
starting at all tape speeds The eesv access heed block grves straight
line tape loading. and the deck can be operated in either horizontal or
vertical posrtlons

Each deck is littod wrth separate Erase. Record and Replay heads. 50
that oll-the-tape monrtonng is possible whilst recording. and the Output
swrtch gives instant comparison at the original and recorded Signals. This
can be done eurellv on the internal loundspeaker or the signal levels
can be checked usually on the meter. which can also be swrtched to read
tho record bras.

Up to 10 Watts rs available from the output stage and this can be
made subrect to separate Bass and lrublo control grvrng boost or cut.
Either internal or external loudspeakers may be used and an altematrve
Low Level output is provrded There is also a 6000 emitter follower
output which Will give a Signal independent 0' the Output. Bass and
Treble controls. The tape can also be monitored on last wrnd [but
muted to avoid discomfort) for accurate place location on the tape,

On record. muting ts given by separate gain controls lot the Micr0<
phone input and the Line Input (suitable for radio or crystal and contour.
pack-ups). All connections (except the Microphone input) are on 3
panel at the rear of the recorder. and the instrument is mounted on a
rigid metal frame which lacditates removal lrom rts portable case and
its inclusion in alternative cabinets.

TO

no I, HMOGMN - UNCASED M00

The Model 713 rs e monophonic recorder operating on the upper
half of the tape wrth lecilities as described above The Models 722
(} track) and 724 l} track) are stereophonic recorders With each
channel identical to that ol the mono recorders The two internal
loudspeakers are led separately lrorn two 10 Watt output stages and
a Record swrtctr allows stereo recording or mono recording on either
track. On rnono operation a swrtch can be used to connect the output
of either track to the Line Input of the other track and this can be
utilised to produce "rnultr play" recordings. or alternatively to give
4 input muting on either track or echo wrthout external connections
The Models 702 and 704 are Similar to the Models 722 and 724. but
do not have power amplifiers or loudspeakers. the third output berng
at low level.

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The tape drrve wall switch oh and the Reset" lamp light up it-
(a) the aqualisation knob is turned while running.
to) the speed change knob is turned while running.
(c) the Auto stop operates
(d) the Forl stop operates.

in each case the Function swrtch must be returned to "Stop" and
the "fault" corrected before the "Reset" lamp wrll go OUL

The dock will not function if the "Reset" lamp is on

Tape loading

To load the deck wtth tape, the two retaining knobs should be
unscrewed from the reel carriers. The reel of tape to be recorded or
replayed should be titted onto llio iett hand tee: carrier (Fig 5) and
the empty spool onto the right hand reel carrier.

The head cover at the centre of the deck control panel should now be
raised and the loading knob moved away lrorn the heads to open the
loading gate mechanism, which Will latch in the open posmon. The
tape can then be inserted in a straght line between the slots In the
side DIDCGS as shown in Fig 5 The end at the tape must be taken
round the auto stop guide as shown and attached to the right hand
spool. The loading knob should then be depressed slightly to unlattzh
the mechanism and to allow the loading gate to close, as unless this
is done the recorder Will not function.

ll tequrred. the reel retainers may be screwed back onto the reel
carriers to secure the reels during transport, or to prevent them riding
oil with the deck running in the vertical position (this is not necessary
when using reels fitted with their own "Hublock" lacrlrty).

When using a tape fitted With a foul at each end. the tape should be
wound on manually until the toil has passed the toil stop. before
turning to "Pause" or "Fast" (see page 20).

Tape Speed

The Speed Selector knob ts Situated at the rear centre of the deck. and
selects one of the three tape speeds The knob Ishould be turned
counter clockwise to obtain a faster speed. or clockwise to obtain a
slower. until the required tape spood is shown in the aperture above
the knob, The Equaltsatiori swrtch on the toll of the amplilier control
panel must also be set to the same speed as it is electrically Interlocked
with the speed change switch. Failure to do this will cause the "reset"
lamp to light up.

Play

On turning the Function knob to "Pause". the three motors are
energised and the drive for the capstan/flywheel started, so that the deck
is on "standby". The tape drive is started by turning the Function knob
to "Run". and as the capstan is already turning. tho start is practically
instantaneous

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HEEL
HEIGHT anus:
ADJUST

FIG, 5. TAP! LOADING

Temporary stopping ol the tape is obtained by turning to "Pause"
while at the end ol the tape the Function knob should be returned to
"Stop".

Record

The Record (and erase) function is obtained by pressing the Record
button and turning to "Pause", then "Run" To prevent acoldental
erasure. once the Function knob has been set to "Pause" or "Run", the
Record button cannot be prossod unless the Record Release catch is
moved to the left. On allownrig the catch to return to the right. the
Record button is locked down in the 'on' Dosmon.

The Record button is released manually by movrng the Record
Release catch to the rlght or automatically on turning the Function

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angle the joining procedure is the saute. although in some casaa more
care may be needed to encore that the cut is made at exactly the right
paint on the tape.

First of all. one of the pieced ol tape should be placed. backing
uppermost along the channel in the splicing block and pressed gently
into it. it necessary aligning the correct part ol the tape opposite the
appropriate slot. A very sharp cutter or razor blade should be drawn
smoothly along the slot and through the tape. The unwanted part
of the tape should be removed and the procedure repeated with the
other piece of tape which is to be joined led in from the other and. On
removing the second unwanted length at tape. the two parts to be
jomed are left in the channel with their ends accurately bultad together.
The piece ol splicing tape can now be pressed linnly on to the tape so
as to cover the joint.

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Two basic sizes of splicing tape are available and this determines the
precise way in which each ll applied. The § inch wide splicing tape
should be applied across the tape. which should then be removed lrom
the block and the surplus trimmed level With the edge of the tape. The
trimmed splicing tape should not project over the edge as this may catch
In the tape guides: on the other hand the trimming out should not
encroach too much into the magnetic tape as this will reduce the signal
at that point. which is particularly important with quarter track tapes.
The other size of splicing tape is the same Wldlh as the recording tape
and a strip about it inch long should be placed along the length of the
tape. This must be laid very carefully and it it is not quite accurate. any
overlap ol spllcmg tape must be removed.

Norah-When retrieving the tape Item the channel. it is advisable to
"peel" the tape out at an angle. since to pull it out vertically may damage
the edges of the tape.

It required. steps a and b can be combined by placmg the two tapes
one move the other before making the single cut. The top "unwanted"
piece of tape should be removed immediately. the other being removed
alter the splicing tape has been applied.

It a splicing block is not available. the two pieces of tape should be
held firmly together and the appropriate cut made using a pair at sharp
scissors The two and: should then be buttod together accurately and the
splicing tape applied to the backing. when it can he tnmmad as usual.

Spoala

The real camera on the Series Seven Fenograph recorders are specially
desogned so that any type of spool contorming to the international
standard can be used. to accommodate dillerant thicknesses ol spool.
the reel carriers are adiustablo in height by turning the screws indicated
in Fig. 5 :~ clockwise to raise and anti-clockwm to lower. To cater lor
vertical operation of the deck. reel retaining knobs are provided for
ordinary spools and these are also uselul if it is required to leave the
real: on the recorder during transportation, However. the Hublol: reels
have a built-in devrce lor this and when lining or removing them the
small protection should be moved in the direction of the arrow. The
tape can also he lastened to the reel by pressing one coloured portion
radially inwards and inserting the tape and behind the other.

Agaln, drilerent sizes of spool can be used on the Farrograph from the
maximum diameter at 8; in. to the very small. but while the performance
may still be satisfactory when using the small "Mirage" spools. the
tape speed constancy cannot be guaranteed it those having an inside
diameter at less than 11 in. are used. Also. the brakes are adjusted lor

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Ptowded the phennmenon tn be monitored l; cauahle c-l being Cun-
vertud mtn ethn' 1' SIIJIIHIS ll (an be recorded so that llllUfllldllDfi hr. the
last lew tttlllull? 5 always avatlable. With the taue actrng as a ' memnry
loot)". One examale ol :nts I5 when we. remrdet ts. ananged m F-flvllt'll
all as soon as a fault occurs . the tape than (antenna a ll,'l|\ldllh_; at the
Conan-ans teadmg up to the taut:

Loading

Before. mrmntmrt 5. maseettre should be Inadcd \A'Illl the. required
length ul tape ard luv suttslattmy pct .Vnrnntre llIIS slmultl nut can and
that for the maxrmum running times quota! lht} taut: should lJr: lulu-n
trot" a reel ofAcelate hased tape. ntelerablvwoll aged. and on no accuunt
should PVC or Palyeflu (My/an based tape be used as these cause
btndtng and smkmg between the leavers (ll tape In the c.3558tte However.
If the SDE'IIBI Graphitad tape 55 available tlm tmrttu-mhle playing; tum:
may be doubled :nr every ntrule of loop at ' Iltv'SlfiL 31L II at tutu:
5 required (18$ it at 33 unuFe ), up tn .3 naxtr w; of lE>CI ft

the three sunwa (and the" nuts and:.t).1tr'tl.~'.}.'ir(rt.nd1""? edge ot the
cassette should nu rernuwd and UN: emull peg m: ned as. m Fun 19.
The start of the tape should be passed from tlu unturdu thtuuuh to tho
insrda at the t'assette hetwaen the. tnurth and hlth YLIIILIS uluntcc In an
ant tclonfltwrse Ulltjxlltjttt from the peg and the tape wound clockwise In
the cunvu'ttlunal "wanna Insutc" method over the. peg The tape ends
should be sultced tuguthur. w fttuul tvwsla. team/mg] :1 lot 1: at {mun-xi
mately 18 Inches outsrde the cassette. then the peg bllUUld hr- run uchd
and the three. spacers 3rd straw: rohtted

Mounting

When us-ng tlr: Lasgette, the eel mtrrers are nm used and the takemp
reel mutm shuuld be 00:. etmnw,<;~r,l This l$ done lw mmnettmg .1:, ll tn
narrow the recorder trot" «ts Lass: as on page 37. will thu ruraht hand
tool motor Is amused at the war (there IS no need tr; tumuw thn ('laSSS
entirely tram the case. and the speaker leads should he Ielt plugged In),
The two pm sncket an the take. up mntm should be rammed and titted
onto the amuccnt 'uumrn-,~ pusttmn The tmmder man than he ltttééd
Into thu cast thu fuses ru IVlSC'lUd and the Inrstrunmnt tr:r,:,mru,-Ltr:d to
the mains

The cassette IS mounted as shown In Fug. 19 by two Eaptlvé sum-.5
\A'thh fut rntn hank humes on the def-k plat nnrt the tape t5 tl readed
through the hands An tll: uf.u..tl way fl-.l~'-(l\l}' ulhlle the tum w. running
them must be little or no {UHLRIUU "l "'9: tupu bclnt; mwound urvtu tlnr:
cassette and therefore the tape must not pass round the auto stop arm
as usual Tn prevent It t'nm operating the arm must nave a small were
of inaulatmg maternal plated hetween I .wrt the fixed umrte.

l) U

5K3 9. (NDLKS-S (00' Ckfififlli

Operation

In ouerahan the tape >5 pulled horn the: Inside of thfi Cassette by' the
dapstan dnve and due tn the drag between adtawnt turrs, the whale mass
ll tflon wrll tr,e'w.ttwe z HIIV nn the arodused sutlace ml the Lias'scttc and "Ira
Pltk wlers. thug lrfu'l'llfl'lt] the tape on the outs da. When ltrst run

bl

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APPENDIX A

OPERATIONAL FAU LT ANALYSIS

Symptoms

Possible Operational Causes

. No "On" lamp: tape
will not run.

Mains fuse blown Mains lead or
plug not properly titted. Mains
selector knob loose or wrongly
positioned.

. "Reset" lamp illumin-
ated: tape will not
run.

Tape wrongly set round auto-
stop. or fail on tape contacting
lotl stop. Speed selector and
Equelisat-on switches not eat to
some speed.

."Reset" lamp not on
but tape \Mll not run.

Speed selector has been turned
when Function switch not at
"Stop". Return to "Stop" and
turn Speed Selector to adjacent
speed then back again.

.Alter turning from
"Run" to "Stop.
Function switch will
not return to "Run".

Function switch has been turned
too far and Fast Wind catch has
engaged. To clear. move "Lock
Release" sideways.

. Known. well recorded
tape will not play;
tape runs but no indi-
cation on meter.

Output switch at "Source". Tape
incorrectly positioned in heads.
Piece ol splicirg tape sticking on
replay head. .6. lute blown.
Replay control A" at minimum.

. Tape runs. indication
on meter but no sound
lrom speaker,

"Output" control at zero. in-
correctly wired plug in Speaker
output. Short circuit plug in Low
Level output.

7, Tape replays but with
poor lrequency res-
ponse.

Bass and/or Treble controls in-
correctly set Accumulation ol
dirt ortapeoxide over replay head
gap.

Appendix A-contmued

l,-

3.

Symptoms

With Record button

pressed on "Hun.
lope erases but does
not record.

Possible Operational Causes

Appropriate gain control in-
correctly set. Input plug not
properly inserted or in wrong
socket Connecting lead faulty.

g. Signal recorded but

previous recording in-
completely erased.

Piece ol splicing tape or tape
oxide covering working face at
erase head.

10.

Signal recorded
weakly. With poor
frequency rosponso

Tape coating outside instead ol
inside. Bias control "B" turned to
minimum - check by setting
meter to read Bias ( at 7; iii/sec).

l1.

Hum recorded on tape
(check by changing
replay speed - il hum
recorded its frequency
WI" also change).

Microphone (and matching unit ll
used) in hum field. Microphone
transformer or leads insufficiently
screened. Microphone leads or
stand not properly earthed or in
contact with mains leakage paths.

12.

Take-up reel carrier
appears to run not.
especially compared
wrth supply reel center.

It is normal for the take-up reel
carrier to feel hot to the tauch.
(The wind back reel motor is not
energised on "Run").

13.

Auto stop lails to
operate (after bu-lt-in
delay).

The contact has become covered
with tape oxide. Clean the contact
lguide at the end at the arm as
described in "Care and Marn-
tenence". page 44.

1.

Tape Winds unevenly.
especially during very
last wind.

Heels incorrectly set lor height.
Tape has stretched non-uniformly
and is concave or wavy, leading
to odd layers winding on at
dillerent heights.

15.

Turns Counter does
not register or makes
a clicking none

"Zero" button has not been reset
correctly, lreas button fully down.

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