Teac W-470 - 5 Electrical Adjustment and Checks

w-470
5 ELECTRICAL ADJUSTMENT AND CHECKS
PRECAUTIONS
1. Before performing adjustments and checks clean and demag-
‘netize the entire tape path.
2. Make sure the deck is properly set for the voltage in your
locality. j
3. In general, adjustments and checks are made in the order of
L-ch then R-ch. Bouble REF. Nos. and test point designations
indicate L-ch/R-ch. (Example: R11/R21)
4, OB is referenced to 0.775 V. Ifan AC voltmeter that references
0 dB to 1 V is used, appropriate compensation should be made.
Oscillator
Distortion Analyzer
Attenuator
LINE IN OUTPUT
. The AC voltmeter used in the procedures must have an input
impedance of 1 M-ohmes or more.
. Note the “Deck settings” at the top of each chart. The settings
apply to all check for a specific chart unless explicitly stated
otherwise.
. Since this deck has an automatic tape selector, be sure to use test
tapes that have tape position detecting holes.
Oscilloscope
AC Voltmeter
1kHz Filter
Fig. 5-1 Basic test setup
Oscilloscope
DECK
under TEST
OUTPUT AC Voltmeter
Fig. 5-2 Test setup for azimuth check
Azimuth Fixed
adjusting screw
Fig. 5-4 Azimuch screw location
O° (IN PHASE) 45°
90° 180°
&) AS
Fig. 5-3 Confirming phase relationship
AC Voltmeter Frequency
Counter
T.P on Main PCB
DECK under TEST
Fig. 5-5 Test setup for bias adjustment