Leak Stereo 30 Plus Service Manual

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STEFIED ED PLUS
INTEGRATED THANSISTORIEED
AMPLIFIER

INSTALLATION - DFERATIDN - MAINTENANDE

IMPORTANT

Do not tuttnuct nny AC Urdu-vice (TV "lnpeor Rudtol to [he
tnut intte lllgh hr potettttnls tm thetrehnsets enpuhle oi ottu» u (climb dntuuee to the
ntnphlter

.tcren .w 16' amplifier Thesc demos
Sumo 10 Plus'

INSTALLING THE STEHED 3° DLUS

'te wood cuse

lr Hm llun: bought the ~htereo su Ilus' ulrendy lnutlllcd tn the stnndunl LLAK tlccur'
t tounttng ol tlte nntpluicr ts completed
it \ml hl\'l: bought the 'Slcrcu in Pltu' tn chimi» lornt l| run he mounted u LEAK luncrlanlplifier
wuud cm or o u pnnel oruny tlttclnetethmugh .. cut nu ol llfi, . 151mm; x IUcms) To ntount
on u put p the hotly or the untplrlter through the run unttl the trout plnte hutts ng ml the punel.
then puss llte l nped hrncket over the hack of the nntplirter und in n by passing the wing screw
lhrmlgh the hole n the bracket and inlo the thrended hank-bum in the ccrllr: oi the rent panel on the
utnplttier. Ttghten the g \crcw jll>| enough to pretent the lront plutu oi the ontpliner lrutn slipping
on the pnuel
The rnnins truuslorrner prtntnry ts wound lot voltuges ul HO. 7. IJU, 210,230s150(40-60 Hz). The
etreulur uoltnoe selector lnlalked wons on the back or the nrnphttert thould he wilhdmwn to its
lullest exlcnl. mulled so Ihdl the arrow indteutet the voltage nenrest to your supply and then reinserted
The nntnlilier K filled wl|h n IS-Ils [4-mclrcl power cuhle. either Zecum or J-cam According to the prnc-
tree or the eottntrt to which n s shipped This enhle should he connected to the domestic power
fill-ml): .15 (allows
, um: cnole it me pouersupply soelet hus n third leurthl cnnlacl. the grcclltydlnw wire should
bl: mmlcclcd to the corresponding pin on tlte power \uppl» plug. The red or hrowu wire should
he mnliefled to the 1m: pin lusuully marked 'L'l und the hluck or blue wtre should he connected
to the nculral pin (murdh nturhod Nl
ii the sockel hue only two conmcls then cnnllcd the red nnd him or hrown nnd hlue wires to
the pin or the plug lttttng thts socket. Cm nfl the green yellow lend .tnd run n sepnrnte canh
lgroundt lend iron. the EARTH' terminal on the renr or the chussis to the water system or to
the steel oondutt etnu the house wirlng. provided that these tystetns thernyeltes nre properly
untried,
tlu 2.core enhle The plug titted to the rutwer Ctlblc should he connected to the domestic power

s pply sockel A seputute enrth lgroundl lend should he run lront \hl: EARTH' tern-tinnl on the
or the ch t to the wnter xyslcm or to the steel Colldllll enenstng tlte house wtring. proutdeu

thnt these systems lllcmxclvcw re properly grounded

it it had pruetice to onttt this enrth eonneutton. nnd to ensure lreedont lront hum (caused hy

-ennh loops') no other ennh (lenccnun shimld he madet

The ampluier is swttohed on hy pretsing the hunon ntnrkud PDWER DNOFF'.
Double sockets tnnrked 'AC ()l'YLETS' ute titted no u Convemenl source oi power supply ror lunh
rubles. radm tuners or tupe recorders The power tuken lront these sockets should be hunted to loo
walls or thereuhouts. These souhets uru not fusm hut are controlled hv the nntpliher switch,
The umpliliet has heun designed to opetute under dumcsllc conditions lot the reproduction of speech
.unl ntutte nnyuheru in the world. Due In the very small umount uI hunt generntetl by the umplilier it
ts possible to mount the ehneste model or the ntnpltrter in u sutull cabinet and tt is only necessary to
ensure thnt the Vcnulflung slots in the cuter plates are unobstructed, Sinewnve testing at lull power
output should he oi short durution. pnrtlculurly ut high frequencxes. otherwise overhealing tony Mun
and me | GA DC (use um hltwl
Fruit t ltt utld on m the norntul AC ruse rind tn order to use the nntphtu-r ntnttntunt protection
ngntnst llhllsc we lithe titted n quick nettne l M or (use ( e \lmuld he tnlren to nuoid shotttng the
loudspeukcr lends no tins nnty blow the ruse. out in order to cmu tlt contingency we have supplied
udqlaukrx or nny tntpetluttce lrunt 4- 5 ohm; rnuy he used and they should he connected to the plugs
g the rntir or \lvckcb tttnrled LOlDSPEAKERS 445 OHMS R und L'

tut

l

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I! Will he sun 1mm lhc Circuit diagram |hm one hide M the loudspmker Wllinfl is connected [0 [he
chassis, and no osher pars oi she loudspeaker w' 'ng should he earshed elsewhere.

ii you wish Io use a loudspeaker which has a huih-in marching ssansioruser ie.g. a lull range elecsro.
slalic loudspeaker may he necessary so connecs 2 ohm 2 wars resissors sn series wish one of the swo
leads conneesinp each loudspeaker so she ~5seieo Jl) Plus amplifier, Failure so connecs shese resissors
may resuh in a iorm or low rreoueney insrahslisy depending on she char serisncs ol she marching srans.
former in she loudspeaker.

Phasing is is visally imporsans shas she diaphragms ol your swo loudspeakers move sn phase
she some direction as ill: some inssans. To make sure at shis nose very carefully she follnwing .
Firss your loudspeaker eahle muss he colour coded, e.g. red and black. ll you are using idensical loud.
speakers (os you cersain should ii you want srue sscreo) she manulacsurcr will douosless have keps so
a cousension when marking the seminals, very oflm simply red and hlack in shis case she loud-
speakers will he in phase when connecsed as shown below

esn

RED WlRE- RE

3 :3 D
/L E Wm: ( LOUDSPEAKERL
LOUDSPEAKERS rFO 5
4-15 OHMS \J aeuwsn: D
R %< [OUDSPEAKER 'R
CKWFE BLLK

ii ynur loudspeaker serrninals are unmarked or you are using dissimilar loudspeakers you can check
she phase as ioilows: place she swo loudspeakers as close sogesher as possible; depress she hunon
marked INPUT [1' and ses she inpus swisch Io PICKUI l'. Connecs an unscreened lengsh of wire
(aoous its.) so she PlCKUP l R sucker. Tum BASS' canlrol so maximum and shen sum up VOLUME'
mull-01 unsil she hum picked up hy she unscreened lead is fairly loud. Then reverse she leads so one
loudspeaker; she eondision which gives you norieeahly more hass hum is she correcs connecsion. . ihc
loudspeakers all in phases

PHONES'. A 3-eonsacs jack sockes is provided on she irons panel so enable she user so connecs a pair
ol ssereo headphones fur personal lissening when is is nos desired so use a pair cf loudspeakers,

The ~5sereo so Plus' is desohsched lrorn she lacsory wills a dummy plug insersed in shis jack sockes so
balance she panel layous and improve she appearance or she amplirser. ll you Wish so use headphones
shen pull Dul she dummy plug and inscrl lhe headphone jack plug.

We have wired shis 3~cm1tucl jack sockes so cenlorm so she usual psacsice adopred by headphone
manufaclums i .. she Icfl channel ouspus is oonneesed so she nip: she s-ighs channel outpul is eohneesed
so she -ring' and she common connectlon so hoch channels is connecsed so she sleeve'.

If she headphones you possess are no! lcrminaled in a Leanna! jack plug shen a plug or shis sype
should he ohsnined from your radio dealer and conneered as shown helow.

stszlEnmluL

COMHOII HIRE /

3' CONTACT

NEADPNMES Tull JACK PLUG

Ilnc'isnnllul.

If your ssereo headphones are supplied wish a tour wire ouspus lead, one lead from she righl hud-
pseee and one lead irons the lefl' headpiece should bl: mined and connecsed so the sleeve' sermiua n
The oorrees phasing oi she signals lrom your ssereo headphones is very imporusnl and in au prohahilisy
she manufacmre of she headphones will have indscased which leads should be loined sogesher and taken
so she sleevc seminasion. should shis iniormasion nos he availahle shen proceed as in paragraph is
abovgrrmvgrsing she conneosions so one headpiece when she condilson which gives noiiceaoly more
bass hum will he correcs,

Two 100 ohm resisrors insoL and RSGR) are wired in series wish she L' and R headphone connec-
lions ro enable mosi headphones so be direcsly connecsed so she sockes. If. however. {In headphones
shar you are using do nos give sasislacsory resulss is ma , be necessary so connecs auosher resisror across
each headphone or to alter the value ol she resissors i have been iissed inside she Stereo 30 Flus
ampliiier This is because she impedance and sens oi headphones VancK consideruhly hesween
she nsanulacsurers