Philips 840 u service manual

Page 1

STRICTLY CONFIDENTIAL

FOR PHILIPS SERVICE
DEALERS ONLY

ID IH II IL ll ID

SERVICE

MANUAL

SUPER-INDUCTANCE
RECEIVER
FOR A.C. AND
D.C. MAINS

Type 840U

GENERAL REMARKS.

Thls mum can be annealed cube: m h lx, ur
AL. wins supply wllhln h waltnge range ol mum
volts. and within a kwuemy mm ol 25400 cydcs,
mm: cnmrlll knobs ale pmvidrd The volume
mnlml, as all u Ihe ontlfl swmzh are upcmmd
wlm lh'e lefl- hand lamb \vhllethzcmm unelsmd {m
tuning The light mm knob IS marked in. h w
:pol, when thi: spot polnls lo llle leil, (ht. m is
mnnecmd {or :1 WM mug? lmm 1807560 mums,
Mule wth the 5pm upnght the mam i: col-medal
l: 3 mm range [mm Magoo mam. wllh llm
ipl)! pmmulg m the light l mm m h wavemngm of
1,590 mmreg l, sulmhnd in. A manls sol-m ml llw
luck panel (snlcty swltdl) ls pmudnd which hum,
"mummy mum llh. recs-wt l-lelu-lwlly dead wllhn
llle back i. remwwd

IMPORTANT.

When ndlusfing. lasting ol- pairing the
recllvzr it in Ileainblt 10 um: In A.C. supply
whlch would have I double wound transfurmer
buwean the supply and «1: receiver wilh m
second-[y wlndlng no! nnhea. .

CIRCUIT.
The modver 13 5401! ha, IWU lulled circuits, mm

between me aerlal and mu Hjl mlve amlllnr between
the HF, wave and lhc ammo; mm

The hhml .3 cnmecmd m 517 u, 000 Ml 1 and m:
coil unil El 52, 53 and 54 \ndu » Coupled my my
grid clrcull of the H F.v1]\e Ll {V in) Th2 mm
chem ol L1 is luaucuwly l'mlpkd by lhl ml! ml
55 5A5 57 and 55 wilh tho gnd mum (ll {hr llmmlr
vaive LZ 13913)

Romance czpacity ounplmg ls used Iar Ll hmplm
mdun, Amman vulumc mmml ha: 1m mum
pomtcd The resist m Rglwhlch ls cmmcckd m ll.»
gml clmlll ul 1.2 will cause a (imp m the ill hm rm
L1 m 1m R15 when a strong sighh mm ml
incmasc a! m: gxid current :2! L2

The halter circufls at L1 L2, L3 and L4 are connected
in series, while the pilot lump m» 3070, L6 (10 ml,
0,2 lamps), and the handler L5 1(1) m lnmrplmwd
in the same elm-ll L4 (on) has 15.1 realfiuv when
(he m 5. connected m A c mama and h» l> c, ml.
Miss lesenea resistance An emalamlspulm
nl high impedmce can be connecwd m the 11mm
mnduy winding of the output transformer

A luuslance kl7 lumqmlell u. m gl-hl circuit
ol L3 (Pen. 26}, 'and n cnmlcdefl clone lo fill: vlllw
tap and .5 endosed' m gyms nu Cunncction {mm
m valv: up w the {asislnncr ax \l'l'll as the mmnrc
incl! am wemcd R17 serves to prevent 5m,
uscfllnting a: Li.

Th: wave (mp 514, 515, czs, B lulled m a mm»
length ol 1,500 menu, ml attenuatcs l," rllll
wnvelexlgtll,