Scott 399 Service Manual

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H. H. SCOTT
MODEL 399

<-_-_7

TRADE NAME H. H. Scott Model 399

MANUFACTURER Herman Hosmer Scott, Inc. , 111 Powder Mill Road, Maynard, Mass.

TYPE SET AC Operated 23 Tube FM-AM Receiver 1th Stereo Amplifier

POWER SUPPLY 105 - 125 Volts AC, 50-60 Cyc1es RATING 175 Watts, 1. 5 Amp. @117 Volts AC

TUNING RANGE-BROADCAST 540 - 1600KC FREQ. MOD. 88 - 108MC

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l.

6.

8.

9.

ALIGNMENT INSTRUCTIONS

Use only enough generator output to provide a usable indication.
Suggested Alignment Tools: Al Thru A6, Ali 'Ihru A15, A17 Thru A22. .

A7, A8, A9 ...........................
A10, A16, A23 .........................

A24, A25, A26 .......................

AM ALIGNMENT-SELECTOR IN AM PCBITION

ALIGNMENT INSTRUCTIONS-READ CAREFULLY BEFORE ATTEMPTING ALIGNMENT

GENERAL CEMENT #5097, 8727

WALSCO #2515

GENERAL CEMENT #5004, 5008, 5009

WALSCO #2520

GENERAL CEMENT #8282, 8606, 8606-L, 9295, 9440

WALSCO #2526, 2543, 2544, 2545

GENERAL CEMENT #5003, 8271, 8275, 8276, 8609,
8721, 8722, 9150, 9298

WALSCO #2516, 2518, 2519

F SIGNAL SIGNAF RADIO CONNECT
GENERATOR GENERATOR DIAL VTV M
COUPLING FRE 1! UENCY J SETTING

High side thru . lmid to 455KC (AM) AC probe to po

Ipin 7 (grid) of AM Converter (400m Mod.)Tuning gang . Common

Low side to chassis. fully open. to chassis.

High side thru . Olmfd to AM l600KC

antenna terminal (disconnect

shorting link). Low side to
chassis.

H n

ADJUST REMARKS

int Al,A2, Adjust for maximum deflection.
A3, A4,

A5,A6

A7,A8,
A9

A10, Ali
A12, A13

I! H

1400KC
(lOKC Mod.

l400KC Signal

Al4,R12 Adjust for MINIMUM deflection.

1

lOOOKC

'Q I.

455KC
(400% MOd.

FM IF ALIGNMEN

Cronnecz twoimaged loo-K (+ ifiesistcTrs in series from point

alignment point as show}? on the schematic.

to chassis. The junction of these two resistors is

'1

A15

T USING AM SIGNAL GENERATOR AND VTVM-SELECTOR IN FM POSITION

L

SENAT SIGNAL RADIO
GENERATOR GENERATOR DIAL wafga
r l ICOUPLINQ FREQLLENCY SETTING
. JHigh side thru . Olmfd to 10. 7MC (FM) D probe to po
pin 2 (grid) of FM Mixer. (Unmod.) Point of non- . Common
1 terierence. to chassis.

ILOW side to chassis.

F

I

L1

D probe to po

. Cgmon

to point

-

ADJUST I

int A16, A17 ,I
. 18, A19,

REMARKS

Adjust for maximum deflection.

int Adjust for zero reading. A positive

and negative reading will be obtained
on either side of the correct setting.

FM IF ALIGNMENT USING FM SIGNAL GENERATOR AND OSCILLOSCOPE -SELECTOR IN FM POSITION

m nulation an-

Use frequency maulated signal with . I

OKC sweep. Use 120% sawtooth voltage in scope for horizontal

deflection.
SIGNAT SIG'NAL RADIO CONNECT I
GENERATOR GENERATOR DIAL ADJUST I REMARKS
L 1 _COI£LIN§ FREQUENCY SETTING SCOPE ,
High side thru . Olmfd to 10. 7MC (FM) Vert. mp. to A16, Al? Disconnect stabilizing capacitor C4D.
pin 2 (grid) of FM Mixer. (450KC SWp) Point Of non- point . Low A18,A19 Adjust for maximum gain and symmetry
Low side to chassis. interference. side to chassis. A20,A21 of response similar to Fig. l with

. A22 markers as shown. Reconnect C4D.
" " " Vert. mp. to A23 Adjust to place marker at the center of
point . Low crossover lines similar to Fig. 2.
side to chassis. SLIGHTLY retouch A16 for maximum
amplitude and straightness of cross-
over lines.
FM RF ALIGNMENT-SELECTOR IN FM POSITION
SIGNAL SIGNAL RADIO 4 CONNECT
GENERATOR GENERATOR DIAL VTV M ADJUST REMARKS
1COUPLING FRE o UENCY SETTING _ _ _
JHigh side thru 27082 to PM lOBMC (FM) D probe to point A24, Adjust for maximum deflection.
antenna terminal. Low (Unmod.) iOBMC . Common A25,A26
side to chassis. to chassis.
, " 9OMC 90MC " L7, L6, Adjust for mammum deflection by
Li expanding or compressing coil turns.
10.7MC 'IOJMC

FIG. I

2

FIG. 2