Teleton CD-250B Service Manual

SERVICE MANUAL
Stereo Cassette Deck
CD-2508
Specifications are subject to change without notice.
Oberhausener Str.17 4000 Disseidorf-Rath
Tel. (0211) 65 30 81 TX 858 6768
Technical Service Organization
Waterhouse Lane, Chelmsford, Essex.
Tel. 0245-54621 TX 99338
Belgium: TELETON N.V.
2200 Borgerhout Belgium
Prins-Leopold-Straat 28
Tel. 03/361045 TX32508
03/357670
Netherlands: TELETON NEDERLAND B.V.
Marconiweg 10. Vianen
Tel. 03473-3744 TX 40581
France: TELETON Electro (France) S.a.r.l.
21 rue Paul Lafargue
94270 Le Kremlin-Bicétre
Tel. 677 6934 TX24 468
Switzerland: TRANSACO AG
Kanzleistrasse 126 8004 Zurich
Tel. 39 45 60/23 50 40 TX 52 362
ALIGNMENT PROCEDURE
1. Tape Speed Adjustment
Equipment Required:
a) Standard alignment tape of 3 KHz
b) Wow & Flutter Meter with Tape Speed Meter
c) Amplifier
Procedure:
1) Connect the deck and speakers to the amplifier.
2) Connect the Wow & Flutter Meter to one of the
speakers and playback the standard test tape.
3) Adjust *VR on the motor electronic governor circuit
to indicate 3 KHz on the center frequency range of
the meter.
*This VR is installed inside the motor case.
The VR is covered by a black rubber shroud, but
there is a cross-shaped cut in the rubber to allow
access to the VR.
. Head Azimuth Alignment
Equipment Required:
a) Standard alignment tape of 10 KHz
b) VTVM or Output Meter
Procedure:
1) Connect the VTVM or Output Meter to one of the
speakers and playback the test tape.
2) Adjust the azimuth alignment screw to obtain maxi-
mum output voltage on the VTVM or Output Meter.
. Meter Sensitivity Adjustment
Equipment Required:
a) VTVM
b) Test Tape: Dolby Level Set Tape
Procedure:
1) Connect the VTVM to the Din (Aux) Output (L ch.)
terminal and playback the test tape.
2) Set Output Control (VR401, 10KQ2B) to maximum,
and adjust VR103 (50KQ2B) to obtain 1V output
voltage. 7 !
3) Adjust VR109 (5KQ2B) to indicate +3VU on the VU
meter. a,
4) And then adjust R ch. same as L ch.
Adjust Controls VR402, VR104 and VR110.
4. Output VR Level Adjustment
Equipment Required:
a) VTVM
b) Test Tape: Dolby Level Set Tape
Procedure: :
1) Connect the VTVM to the Din (Aux) Output (L ch.)
terminal and playback the test tape.
2) Set Output Control (VR401, 10KQB) to obtain
350mV output voltage.
3) And then adjust VR402 same as VR401.
. Record Bias Adjustment
Equipment Required:
a) VTVM
Procedure:
1) Connect the VTVM to both sides of R125 (10 ohm)
on the printed circuit board for the left channel.
2) Set Selector Switch to Record Mode.
3) Adjust VR111 (100K ohm —B) to obatain 4.5mV on
the VT VM at tape selector chrome position.
4) Confirm voltage value to obtain 2.5mV at tape select-
or normal position.
5) Change the connection to the right channel resistor
R126 (10 ohm) and adjust VR112 to obtain 4.5mV
at tape selector chrome position.
6) Confirm voltage value to obtain 2.5mV at tape select-
or normal position.
. Record Caliblation
Equipment Required:
a) VTVM ,
b) Signal Generator
| Procedu re:
i. Connect a source of 400 Hz signal to Din (Aux) input
(L+R). With tape selector normal position, record on
blank iron-based tape and adjust Record Level con-
trol so that meters read OVU.
2. Without altering the Record Level control settings,
adjust the Fe,Q03 Rec. cal. VR105, 106 (20K ohm
—B) as required and playing back the recorded tape,
the meters read OVU. |
3. Repeat steps 3) and 4) with chrome-based tape (tape
selector in the CrO, position) using the CrO, Rec. cal.
VR103, 104 (20K ohm —B).