Specifications

electrical installation
The HF-81 can be used in two ways for a stereophonic
system. In all cases, plug monophonic sources and
one
track of monophonic/stereophonic sources in the channel
1 inputs; plug the other track of stereo sources in the chan-
nel 2 inputs. It is assumed in what follows that a stereo-
phonic phono cartridge is being used. Monophonic phono
refers to
playback of a monophonic recording with a stereo-
phonic cartridge .
CH.2
32 16 8 .4 G
(J) (]) (J) (J) ()
TO MATCHING
TAP
CH.I
32 16 S 4 G
TO MATCHING
TAP
FIG. 10. SPEAKER CONNECTIONS
a) INTERNAL POWER AMPLIFIERS OPERATED SEPARATE-
LY,
EACH DRIVING ONE SPEAKER OF A STEREO PAIR.
This arrangement is used when there is no
other amplifier
the user desires to include in the system. The
SERVICE
SEL.slide switch on top of the chassis must be set to SEP-
arate. Signal connections are all internal, so only the
speaker connection need to shown (Fig. la, rear chassis
view). The internal arrangemention in
the HF-81 at each
of the positions of the FUNCTION selector are shown in
Figs.
lb, lc, ld, le, H, and Ig, as an aid to understand-
ing the operation with this arrangement.
SPKR.2
SPKR.I
FIG.lb
CHECK AMPL. 1
CH.I HIGH CH .l
LEVEL INPUTS TAPE OUT
CH.I
LOW _--_IPREAMPt r r:r<5NEl t --I
I
POWER AMP L-- SPEAKER
LEVEL INPUTS . CH .I ~ . CH.l ~ CH.I
FIG.lc
CHECK AMPL. 2
CH. 2 LOW
LEVEL INPUTS
Ip~:,~p~! --II PO~~.~AMP ~ SP~~;R
CH.2 HIGH CH.2
LEVEL INPUTS T APE OUT
CH.l HIGH
LEVEL INPUTS
CH.l
TAPE OUT
1-- __ SPEAKER
CH.I
CH.l LOW
LEVEL INPUTS
FIG.ld
STEREO NORMAL
CH.2 LOW
LEVEL INPUTS
SERVICE SEL.
I
P RE A M P ~ SEP ••• jr-
P
""':" O-W ""':" ER :""" AM -:-:-:" P ::-1 L-- SPEAKER
CH.2 I 1 19!:2J ~ . CH.2 ~ CH .2
CH .2 HIGH CH.2
LEVEL INPUTS TAPE OUT
CH.l HIGH
LEVEL INPUTS
CH .I
TAPE OUT
1-- __ SPEAKER
CH.2
1-_'- SPEAKER
CH.l
CH.I LOW
LEVEL INPUTS
CH.2 LOW
LEVEL INPUTS
FIG.le
STEREO REVERSE
CH.2HIGH
LEVEL INPUTS
CH.2
TAPE OUT
4