Sony TC-K670 - Electrical Adjustment Details; Record Level Adjustment; Erase Current Adjustment

Record Level Adjustment
Setting:
REC LEVEL control: Standard Record (See page 12).
test pin CNE707 : short
Procedure:
1. Mode: record
AF OSC
LINE IN
315Hz, 31. 6mV(-27. 8dB)
2. Mode: playback
recorded VTVM
LINE OUT
3. Playback the signal recorded in step 1.
Confirm that the signal level is within the adjustment limits below. If
necessary, adjust RV141 (L-ch) and RV241 (R-ch) repeat the step |
meat
Adjustment Limits: —27.80. 5dB(29 to 33. 4mV)
Adjustment Location: MAIN (A) board
Erase Current Adjustment : TC-K670/K877ES
1. Mode: record
frequency
YTVM
CNE522
test
tape
ot—ilts
2. Adjust RV504 so that the reading on VTVM is
106mV (erase current=105mA).
3. And then confirm that the reading on the
frequency counter is 160kHz.
Adjustment Limits :
Erase current: 105mA to 110mA
Frequency : 160 + 6kHz
| TC-K570/ K670/K677ES
Adjustment Location
—MAIN (A) BOARD—
RV141(L-CH)
} Record Level
RV241(R-CH)
RV121(L-CH) |
RV221(R-CH) ?
CNE522 Erase Current Test Point
T181(L-CH)
T281(R-CH)
RV504 Erase Current
Playback Level
} Bias Consumption Current
CNE521 Bias Consumption Current Test Point
“RV281 (R-CH)
} Record Bias
RV181(L-CH)
CNE707 Test Mode Point