National sa 52h owners manual

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b NATIONAL

MODEL SA-52H
INSTRUCTION BOOK

SPECIFICATIONS

Frequency Range; MW ......... 525~ I605 kc

SW ......... 3.9~ I2Mc

FM ......... 88~ I08Mc
Intermediate Frequency: AM ......... 455 kc

FM ......... IO.7 MC
Tubes & Diodes: 6A8? XI FM RFA 8. CONV.

68E6 XI AM CONV.
68A6 XI FM 8: AM IF Amp.
6AU6 X2 FM LIM.

68A6 XI FM MPX AF Amp.
I2AT7 XI FM MPX I9 & 38.Kc Amp.
12AX7 XI FM MPX AF Amp.
t2Ax7 x3 AF Amp.

I2AU7 X3 AF Amp.

OBQS X4 Power Amp.
SD-IA X4 Rectifier

OA70 X2 MPX RECT.

OA79 X5 AM FM DET. 8. MPX Doubler

SCIS XI AFC

FM MULTIPLEX
M.F.B.

STEREO
AMPLIFIER

Sensitivity: FM ......... 5/LV / lHFM 3000

MW ......... 20,1V / 50mW
SW ......... 30,uV / 50mW

AF Input Sensitivity: AUX ......... I20mV / 500K!) lor I6W
MAG ...... 3.5mV / 33 Km for l6W

CRYSTAL... l4mV / 133 Kn. for 16W
Recjout... 0.1V / 500 Kn

OUTPUT: 30W -- 30W (Peak music power)
Frequency Response: 20~20000c/s $0.5 dB...Amp|ifier section
5 /' N: 60 dB AUX input
Separation: -35 dB
Power Source: II7V-22OV 50~60 c/s
Power Consumption: 98W
Dimensions: W 370mm, H lélmm, D 328 mm
(w 181/2. H 6%. D 123/8).
Weight: I5.0kg (33 lb. l 0:.)

OUTSTANDING FEATURES
HIGH POWER OUTPUT CIRCUIT

6805 push-pull circuit, has high pOwer Output with little powar
consumption.

Have output terminals for MFB speakers as well as ordinary speakers
from 4 to 32 ohms.

MFB CIRCUIT
When COmbined with MFB (motional feed back) speakers, the built-
in MFB circuit automatically corrects distorition and insures full-
throated bass.

DC OPERATED PRE-AMPLIFIER

To amplify magnetic and crystal pickup output, pro-amplifier must be
highly sensitive. Tubes used in the pre-amplifier stage are all DC
Operated, to insure record reproduction at very low noise level.

LOUDNESS CONTROL SWITCH
To compensate for the aural sensitivity of human ears, which have
less sensitivity to bass as the volume decreases. loudness control
is previded for sufficient lows even played at low volume level.

STEREO RECORDING TERMINAL

Broadcasts or phono records can be recorded on y0ur taperecorder,
while listening, via the taperecorder recording terminal, regardless
of the volume level at which it is being played.

3-BAND TUNER~WITH BUILT-IN FM MULTIPLEX

CIRCUIT , ,
Highly sensitive (IO microvolts at 30 dB quieting) FM reception,
Iree from noise or interference. FM stereo frOm the built-in FM
multiplex circuit. Also enioy overseas broadcasts on the short wave
band.

TUNING INDICATOR

When the painter of the meter rests in the middle of the scale, it
means that an FM station is accurately tuned. On MW or SW
bands when the meter points to the maximum on the scale, it is
accurately tuned.

FM AFC CIRCUIT

Built-in AFC (automatic frequency cantrol) circuit automatically
corrects detuning and keeps the set accurately tuned to an FM
station, for distortion-tree reception.

FLYWHEEL TUNING MECHANISM

Flywheel On the tuning axis makes tuning much easier. With a
twist of the tuning knob, the pointer efTOrtlessly glides along the
dial, from end to end.

FM STEREO EYE

When the set is tuned to an FM station broadcasting program in stereo,
the STEREO EYE On the dial lights up in red. This indicates that
the particular program is being broadcast in stereo. If the MODE
switch has been set tO MONO, turn the MODE switch to STEREO

for full stereo reproduction.

FERRITE ANTENNA

Built-in ferrite antenna has outstanding high sensitivity and low noise
characteristic. Ideal for reception on MW band.

REAL WOOD CABINET .

The cabinet is made of real, Oil-Finished walnut with metal front
panel in gold. A deluxe and handsome control center for your hi-
fi system. The oil finish protects the cabinet from scratches and
smear.

PUSH-PUSH POWER SWITCH

PUSH-it is Switched on. PUSH again-it is switched off. The switch
button glows when the set is switched on.

THE BEST PLACE IN YOUR HOUSE
FOR YOUR STEREO SYSTEM IS
WHERE:

* The floor is level and solid

* There is easy access to an electric outlet, gr0und wire, easy
leadingdn of FM and short~wave antennas

* It is away from flUOrescent lamps, electric appliances and other
noise sources

* The rear OI the amplifier is to be apprOximately I0cm away from
lhe wall (for ventilation).

* It is free from humidity, direct rays of the sun and team heats.

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CONTROLS
* A POWER

Push the button and the set will begin to work.
To turn the set off. push the button again.

*BMFB

If you are using MFB speaker systems, you can enioy the MFB
effect as follow,

"0" position ............ MFB circuit does not work.
"l"~"5" position ...... MFB circuit works.
From 1 to 5 the MFB effect increases step
by step.
* C BASS
This knob can be adjusted to the level of the low frequency range.
" D TREBLE
This knob can be adjusted to the level of the high frequency range.
* E BALANCE

When you want to balance the volume level of an FM broadcast
0r while playing a stereo record, you can get proper balance by
- turning this knob clockwise to raise the right volume, or counter-
clockwise to raise the left one.

* F VOLUME
You can get desired volume by turning this knob clockwise to raise
the volume, or counterclockwise to lower it.

* G LOUDNESS
When "ON" provides the frequency response change required by

the ear at low listening levels. This action then permits the volume
controls to function as a compensated loudness control. in the
"OFF" position, the loudness circuit is inoperative, and the volume
control functions as a normal gain control

How to enioy the M.F.B. (Motional Feed
Back) effect

Our ears can usually hear sound having a wide frequency range...
l6~20,000 cycles.

For radio or stereo reproducing systems, it is very difficult to
reproduce sound of this frequency range perfectly.

This means that no speaker can have such a perfect reproducing
ability.

For instance, even a 3? inch speaker cannot reproduce bass
sound perfectly. You can always control the tone of the amplifier
with the tone knob, but it is only electrical control, not acoustic
control.

There is a limit of reproduction of perfect bass sound, acc0rd-
ing to the characteristics of the speaker.

By the "M. F. B." circuit, which.may be called an artificial
brain of sound, we can spread' the lower frequency range, and
raise the bass sound level, varying the characteristics of a
speaker. , '

This circuit works to improve the frequency response and distoro
tion characteristics of the speaker, electrically detecting the motion
of the speaker cone with a special coil and feeding it back to the
amplifier.

You. can enjoy better bass with the MFB knob at the front of
the set.

*HAFC

After tuning in an FM broadcast, turn this switch to "ON, then
tuner autOmatically and precisely locks to the absolute center of
the inc0ming signal

* l MODE

This is the mode select switch. Set the switch in stereo position
for stereo record playing or fM broadcast reception.
During MW and SW reception, this switch has no function.

* J SELECTOR

Select the program source,

for listening to external programs ..................... "AUX" pasitiOn

for playing records ....................................... "PH" position

for listening to FM 0r FM stereo broadcasts ...... "FM" position

for listening to MW (medium wave) broadcasts..."MW" position

far listening to SW (short wave) broadcasts ...... "SW" position
* K TUNING

This is to select the desired station. In the shart-wave band.
broadcasting stations are tuned in on the thick lines marked 75, 60,
49, 4|, 31 and 25.

* L STEREO EYE

* M TUNING METER

On the FM band, the center position will give the best reception.
On the MW and SW bands, the meter works in the regular manner
the point tuned in is the max position.

If you want to enjoy brilliant bass. set the MFB knob to the 4
or 5' position.
To enioy clear sound, set the the knob to the 'l or 2' position.

How to listen to FM STEREO broadcasting

.-

* FM stereo broadcasting is every convenient system because it
uses Only One channel of carrier frequency but is modulated with
two different signals sothat we can enioy stereo sound from one
broadcasting station.

* For reproduction of FM stereo, a FM MPX adaptor" to demodulate
the MPX signal to two different signal of left and right channel is
necessary.

* This set has a built-in FM MPX circuit, so you can eniov FM stereo
broadcasting.

* When you tune in to an FM broabcasting station, the STEREO
EYE" at the right side of dial will light up. Then switch MODE"
from "MONO" to "STEREO".

The reception is then in stereo.

* In some areas where signal strength is very weak noise may
increase. If so, change the antenna to a higher-gain outdoor
antenna and tune in accurately to the station.