Philips 617 a service manual

Page 1

Wm-

DHILIPS 617A

Three-valve, plus rec/zfier. tliree-waveband
superhet for operation from AC mains. Provision
is made for a high resistance pickup and a low
impedance extra loudspeaker. Manufactured

by CS section of the ganged condenser.

The grid

feed-back coils are L15, L17, L19.

An intermediate frequency transformer L20, L21
transfers the signal from V1 to the IF amplifying
stage comprising V2 and a second 1F transf mer
L22, L21 A tapping on 1.23 feeds the signal diode
oi the double-diodeapenlode output valve V3. Delay
volts for the signal circuit are derived from a variable
tapping on R16 which is in the cathode :ircuit, of
V3.

The low frequency signal is fed from the volume
control R9JR9A to the grid of the pentode section
of V3 via the coupling condenser C31 and filter R28

and C39. The pentode section is biased from a
tapping on the cathodexresistanee network R12,
R13 which is decoupled by C32. The pickup
sockets are connected across the volume control.

The automatic volume control diode of V3 is fed
from the anode of V2 via C29, the load resistance
being R14 and R23, from which the AVC is fed to
V1 and V2 grid circuits.

The output from V3 is coupled to the permanent
magnet moving coil loudspeaker L27 via the match-
ing transformer L25, L26, which also incorporates

Continued second column overleaf

by Philips Lamps erL. Service Dept, 74779, '
Cherry Orchard Road, ,Cruydan, Surrey. wmnmes CONDENSERS
L Ohmx ! L Ohm: C "W l C . h
THE aerial input is fed via a switch either to the 1 7 18 32 I? 2 3 25 . RESISTANCES
HF transformer L12, L13 on SW or L6, L7 2 300 '9 f5 .0633] x 2' g: R Ohms R Ohms

of a band-pass filter circuit on MW and LW. An 3 g g? ,{g 1012 31
IF filter L29, C13 is provided across the aerial and s I, 26 22 115 is? g 3
earth sockets. _ z 4 ~ 305 3 2'3 '33 mmfd 34 - 4

C4 section of the triple-ganged condenser tunes 9 j: 48 .25 700 47 35 g
the secondary coils L10, L11 of the band-pass filter 10 H 4.4 26 1 47 mmtd 36 7
and the shortwave grid coil L132 i; .4 25 g" fisoor 5 33 mmfd g; 8

From these circuits the signal is fed to the control 13 " 5 30 ~-, 00145 42 3A
grid of the triode hexode V1, which is cathode 14 I: :5 31 .7 4151'"de 43 r 10
biased by R21 decoupled by C14. The oscillator 15 .. l 32 130 {.9447de :2. 22333 It
triode section employs tuned anode circuits with the '6 " 3'5 is 3333 :047 ' g
oscillator coils fed from the anode via C16 and tuned o sec' in, * Only fitted when'gang hasaluminiutn vanes" 14

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PILOT LAMPS

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DECEMBER. I 944

RADIO MARKETING SERVICE ENGINEER-vii

Page 2

SERVICE ENGINEER
INDEX l944

HERE is a complete index to the receiver reviews
and technical articles published in Service
Engineer Supplement from the January to December
1944. issues inclusive.

Extra copies of Service Engineer " have been
printed throughout the year and at present all issues
are still available.

Make. Page. Month
Belmont . v Jan.
Bush vii Feb.

,, vi June

, iv_ Oct.
Comi- Y! Aug.
Ekco v11 Sent.
iii Nov.

AC86 .. .. .1

301 330, 331 332 336,
31. 353, 376,

421, 422, 425, 461, 463 iv Feb.

414, 415, 419. 439, 441. V Feb.
1813,6440. 465, 465A(BCL

Emerson . .

iv Mar.
,, 425, 433 v Mar,
,, . . 424,427, 428 iv Apr.
Ferguson .. 378 AC vi Jan.
,, 378 AGQC vii Jan.
., >101, 804 Iv May
., 8028 v May
,, 81;]1,882,884885 Ni May
GE . . v Apr.
,, . . iv July
,. .. .. L541, L543, L570 V July
GEC . . . . 4050 . . .. . . V Nov.
HMV .. ,. 459 .. .. .1 v June
.. . . 1. 459 MC . . . . vii June]
442. 443. 570, 570A .1 iii Dec.
Kolster Brandes ,. 74o . . .. . . v1 Sept,
,_ ,, .. $33583 .. .. .. v gee.
A n . . . . . . . . VII II
L's" .. 8108,8111, 8116. 8117, y
8121, 8125, 8128,
129 ,.V .. ,.
Marconiplmne
Murphy . .
Phik'o
t)
,, 50 a
Phili 617A .
,, a 834 A
Pilot Little Maestro
Pye 811
Ultr 121,133,140,150

n
War-time Receiver

Battery.
AC

ARTICLES AND FEATURESV

Advantages of Full Wave Rectification . Sept.
Circuits for Valve and Metal Rectifiers . . . . Oct.

Ferranti War-time V . . . . Mar.

Intermediate Frequencies . . - . . . . A-I Mar.
K-Tel Apr.

May

Key to Valve Makers Code

Mains Sections of Receivers

Matching and Biasing the Output Valve
Modifications to War- time Receivers
Negative Feedback and Tune Circuits
Parallel and Push- Pull Output Circuits
Principles of Low Frequency Stage
0?? and Class B for Current Economy
Transformer Coupling In I F Stages
Vibrator Cirwits . .
Volt-dropping Resistors for AC- DC Sets

VIII-RADIO MARKETING SERVICE ENGINEER

PHILIPS 617A

ContinuedJmm page vii
windings L32, L33 for negative feedback into the
grid and cathode circuits of V3.

Some receivers incorporate 11 matching trans-
former which has an additional winding between
point4and an extra eyelet on the same cheek. Loud-
speakers with 2.5-ohm speech coils should be con-
nected to the 1.26 winding only, but S-ohm loud-
speakers should be wired across both L26 and the
additional winding.

The high tension supply is deriyedirom a full-
wave rectifier V4 with resistance smoothing carried
out by R1, Cl and C2. Some mains transformers
are suitable for either 4-volt pilot lamps or 6.3-volt
pilot lamps ; the former models incorporate a
4-volt tapping point on the heater winding L4 which
is brought out to an eyelet midway between the two

normal outer connections for L4.
122.1 cm ca
® null/:0
,
o a
F3 ®ILOWEA1
50

team

1:25

Q9.

W. 63 .
ramsrrt . ,
CID.
GANGING "'

IF Circuits. -Switc11 receiver to MW and tune
to 180 metres. With volume control at maximum
inject 4? 1/218 kc signal into the grid (top cap) of V1
no a_ .032 mt'd condenser.

'fietune L22 by connecting a 80 mmfd condenser
across it and adjust C28 for maximum ouipu..

Detune L24 in same way and trim C27 Detune
L20 and trim C24. Detune L21 and trim C23.

HF.Circuits.-Adjust variable condenser so that
the angle between the edges of the fixed- and moving
vanes is 15 deg ; the manufacturers can supply a jig
for this purpose.

Inject a 1600 kc signal into the aerial socket and
trim C18, C10, C6, C10 and C18 in that order for
maximum output.

When the gang is of the type with aluminium vanes
the input signal should be 1570 kc.

IF Fflter Circuit-Apply a 128 kc signal to the
aerial socket and adjust C13 for minimum output.

VALVE READINGS

1/ Type Electrode Volts Ma
1 ECH3 Anode . 255 1.2
Osc anode 140 4.3
Screen 70 1.3

2 EF9 Anode 250 5
Screen 90 1.5

3 [Hill Anode 260 32
men 240 5.2

Cathode . . 19 ~-

4 All Healer . . . . 300 51

Pilot 13an 4 vor 63 v (see text).

Name

not for sale

Some of you say Wcd gladly
pay higher prices if we could
have all we want. And we
say Sorry. gentlemen, but.
we simply dont sell main-
tenance Components at prices
lhat arent fair prices; in the
long run, you know, it would
he rank bad business. In
other words,you cant coax us
into giving you stop-gap war-
time components at exorbitant
not even if our

prices, 110,

obstinacy loses us good money.

For we arent out to make a.
wartime pile in record time
fiand then turn to another
We didnt

start yesterday and we arent

line of business.

packing up when the wars
over. The hero - today ~ and
gone-tomorrowers have their
policy.
steady customers by serving

Ours is to keep our

them well and fairly over a
long period. Were not selling
our good name, Thanks, at

any price.

Radiospares Ltd.

44 BIRCHINGTON ROAD, LONDON,

N.W.6 TEL: MAIDA VALE 9386-7

DECEMBER. 194