Panasonic RQ-320SD - Amplifier Adjustments

AMPLIFIER ADJUSTMENTS
Measurement condition:
Supplied voltage ...... DC 9V Volume control ...... Maximum Tone control ...... Maximum
Equipment required:
VTVM, ATT, AF OSC, Oscilloscope, resistors (10, 80, 100Q, 600Q).
SIGNAL SOURCE OUTPUT
ITEM CONNECTION CONNECTION MODE ADJUSTMENT SPEC. REMARKS
If there is no alignment
Head angle tape, you may playback
uvateaue Sis Carats VTVM with 8Q adjustment a music tape and adjust
i ae abea resistor to EXT SP | Playback | screw @ Maximum | 't to the most suitable
adjustment. | alignment tape. sack ae A position for listening
| Jack. ot where the playback
fig. 7. | sound is maximum and
! highest.
|.
er nrat ate Erase current (50 mA)
Measurement of ; bie - Voltage value
—~ resistor as shown Record VR3 50 mV (50 mV)
erase Current. aes = ,
in fig. 8. Resistance value
(1Q)
: | Bias current (0.5 mA)
Measurement of VTVM with 1000 Voltage value
3} recording bias _—— resistor as shown Record ; —o 50 mV (50 mV)
current. | | in fig. 9. = Resistance value
(1009)
kHz — 724408 | vty with 1000 Stop the bias oscillation
Measurement of to MIC input jack. , ;
‘ resistor as shown Record —. 5 mV by removing the
recording level. 1 kHz —30+4 dB in fig. 10 Kecistor BEd.
to AUX input jack. | ‘7 "8 **:
Measurement of 1 kHz —82+3dB | VTVM with 80
5] playback amplifier | as shown in resistor to EXT SP | Playback — lV —
gain. fig. 11. jack. }
i
i]
Adjust the AF OSC to
Oscilloscope with obtain a circular and
Measurement of AF OSC to both stationary Lissajous’
6 | bias oscillator — ends of erase Record = 35-5 kHz) figure on oscilloscope.
frequenc
head
as
shown
in
In
this
case,
the
;
*
oscillation
frequency
is
fig. 12. indicated by the scale
of the AF OSC.
12