UX-Z7MDR
(No.22042)1-41
3.2.6 Electrical Performance
3.2.7 Reference Values for Electrical Function Confirmation Items
Items
Measurement
conditions
Measurement method
Standard Values
Adjusting positions
Adjustment of
recording bias
current
(Reference
Value)
Mode
: Forward or reverse mode
• Recording mode
• Test tape
: AC-514 to TYPE ll and
AC-225 to TYPE l
Measurement output ter-
minal
: Both recording and
headphone terminals
1 With the recording and playback mechanism
load the test tapes(AC-514 to TYPE ll and
AC-225 to TYPE l ), and set the mechanism
to the recording and pausing condition in ad-
vance.
2 After connecting 100 ohm in series to the re-
corder head measure the bias current with a
valve voltmeter at both of the terminals.
3 After resetting the [PAUSE] mode start re-
cording. At this time adjust VR31 for Lch and
VR32 for Rch so that the recording bias cur-
rent values become 4.0µA (TYPE l ) and
4.20µA (TYPE ll ).
AC-225
: 4.20µA
AC-514
: 4.0µA
VR31
Adjustment of
recording and
playback
frequency
characteristics
Reference frequency
: 1kHz and 10kHz
(REF.: -20dB)
Test tape
: AC-514 to TYPE ll
Measurement input
terminal
: OSC IN
1 With the recording and playback mechanism
load the test tapes (AC-514 to TYPE ll ), and
set the mechanism to the recording and
pausing condition in advance.
2 While repetitively inputting the reference fre-
quency signal of 1kHz and 10kHz from OSC
IN record and playback the rape.
3 While recording and playback the test tape in
TYPE ll ,adjust VR31 for Lch and VR32 for
Rch so that the output deviation between
1kHz and 10kHz becomes -1dB 2dB.
Output deviation
between
1kHz and 10kHz
: -1dB 2dB
VR31
Items
Measurement
conditions
Measurement method
Standard Values
Adjusting positions
Recording
bias frequency
Forward or reverse
• Test tape
: TYPE ll (AC-514)
Measurement terminal
: BIAS TP on P.C. board
1 While changing over to and from BIAS 1 and
2, confirm that the frequency is changed.
2 With the recording and playback mechanism
load the test tape.
(AC-514 to TYPE ll ), and set the mechanism
to the recording and pausing condition in ad-
vance.
3 Confirm that the BIAS TP frequency on the
P.C. board is 100kHz 6kHz.
100 kHz
6 kHz
Eraser current
(Reference
value)
Forward or reverse
• Recording mode
• Test tape
: AC-514 to TYPE ll and
AC-225 to TYPE l
Measurement terminal
: Both of the eraser head
terminals
1 While recording and playback mechanism,
load the test tapes (AC-514 to TYPE ll and
AC-225 to TYPE l), and set the mechanism to
the recording and pausing conditions in ad-
vance.
2 After setting to the recording conditions, con-
nect 1W in series to the eraser head on con-
nect 1W in series to the eraser head on the
recording and playback mechanism side and
measure the eraser current from both of the
eraser terminals.
TYPE ll
: 120 mA
TYPE l
: 75 mA