Philips 716 b service manual

Page 1

V] (Supp/mull) THE WIRELESS & ELECTRICAL TRADER February 26, 1938

PHILIPS 7|6B

3-BAND BATTERY SUPERHET

i5.\\'.], L10 (M \\'.) and L11 (LAY) are COMPONENTS AND VALUES
tunnd by 03],; parallel trimming by m i
(132 (MW) and 083 (LW-l : Series (UNI R> (Mi)
tracking by 012 (M.W.] and Cl]. ll. 5). ' ' 7 7 i 7
Reaction by grid coils L12 (swi. CI Tn'°:"Wr°S>fr("W) -- °'°°°°25
1'13 (M.W.) and L14 (l..\\'.). 1; Ar 5..wi1nchyndoiiser1. ooooos
i; M. and i..Vi..mi.ii coupling o-ooooz
Third "alvc (V3- Mullnrd metalhged 14 Bind-puss iiuirnm culiplmgl o-nrli
VPZB) is a v izible-mu hcxmiu operating (-5 i comma. _ i 0.025
:m intermediate [requtlky amplilier With U. 0mm
tunedrpnmary tunwl-xunndui'y iran» (7 065
iimmi Couplings 03-}. L15. L16. 035 1.. m
:ml 036, L17, L18, 037. 1., 1 m
Intermediate frequency 128 KCS. m '02
Diode second (11(1101 iv. part 01 in 0 - 1 l k 0000?"
TWO-VALVE in uencv than (Ar is . ' H We! - . C Cr -- 000! '5
Amrbye m magphnl-ps AFB 5, (spiny double diode yam (v4, Manna U3 VH1. ,u .15.. wiping c.0005
valvu battery g-hand superhét. metalluqd 2132):. Audio m"IL'my com- Cu V2 .G.condcn Another feature heing' ihzit it is ton~ l'°" 1 t'he'l output 5 developed ('15 ViCG-de-Wpfing .1 .. c-r
strucmd in two unity-one for the "955 manual Wlmw tontrol R11, CM V3 S-G.d"-��0ui>lin: 1. .. . 0-0:
the irlquencv changer and the other for "'Ch also 0th 5 load Ssmncc CI7 ' qunmhdctouplilm .. 11 am
the If. sécoud detcctor and output and passed Vla All coupling Wen-0 VlicMhndvbwpi» .1 .. a-s
stages Tlm short-wave rangr covered i,~ (520' C-G' 3515mm" R" and H" mm by c. .. .1 .. 947001
"2-5! m. 1318. 022. R21 0 Penlmlbf Output VBIVL .. rouplingto V5 1. .. om
l V5; Mullanl 131912211» t Fly; 2;) (9°; Coupling to v. A1\.C. .iimie.. 0-0001
1'3Cion in arm 1: Circui y . x. . pnnMLRfihcr 1. .. (WWI
CIRCUIT DESCRIPTION potenual is obtziiubd from potential H.-Il,v_[,a55 M __ .. 0.0m
Aerial input on M.W, and LW. viu divider RIB. R20 :itrnss G113. section of HIT.{ummummdmm ,1 310
coupling coils L2, L3 and small condenser [LT battery Mm LR filtm-uniug 1. u-ooox7
G; 0 capacity couplod bandPass filter, on jade of {cd from L1 in" lmngumpprcswr liming ,. o-ooouj
Primary coils L4. L5 are tuned by 023: 0.151317 3...? 021 pnxfilles D.c, poleflltjial: Bandwswri. ii1w.uim.im o-oooos
Mdfies L17' L8 by C30,? coupl""~' which are deileloped across loud rc~ . Band-mummytuning .. 000049 l
by C4. 05. Ht filter L1. 025 is connected 5. me: 314 315 and [1 back through cm Lanai... sci. MM'. trimmer 0-0000:
acme L2, L3. lung 9")me be i]:c0upling Cinllfls to 1-11". [except on CM Band-pavwcomlnrymningu meow
01, (:28. 0n S V input Isvvm Coupling \' w; and 1_1:_ valves, ,2 viiig :iiicomauc Lani |)~ CODdinSW 02 [7 "PlllOdlC -��011 143- \Y)lulne control. Delay voltage and H2: 03. Hrcuit MW. trimmer .. 00000!
First vaini (V1, Mallard metallised ninimum (3.13. for V3 is obtained [mm Fig: (NJimuizLAl/Jrimmcr .. o-oooog
m3; i> a variable-mu hexode operating potential leldH R15, R16, alxo connected .: '. Inns. rri. tuning .1 woman
as Irequo changer with suppressnr aizross (113. Section of II battery, u-ooox7
grid injection in conjunciion with sew-mite whi [additional delay vnltag 1 _ obiained 0-000
oscillator Valvc 1V2, Mullard metallised hum potcntial divider 312, R13 across o-ooov
PM2IIL). Il l W km N.) "D
-- (i7 2 ll "6
A ll! m
,1 i . ,
1i; M ii
. 5- 7
1.
ii
7 <-+W 2:.
i1 :5] MI
I But!
in
_ am

ii'.
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Circuii diagram of the Philips 7168 3-bnnd banery superher.

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