Telefunken M 204 E User Manual

TELEFUNKEN
Service Information
Technical Data
Power Supply:
Power Consumption:
Tape Speed:
Track Arrangement:
Spool Size:
Playing Time:
Rewind Time:
Magnetic Heads:
Bias Frequency:
Erase Frequency:
Equalisation:
Semiconductors
Fitted:
Transistors:
Rectifiers:
Diodes:
Inputs:
Outputs:
Output Stages:
Frequency Range:
Dynamic Range:
Wow and Flutter
(Pitch Fluctuations):
110, 127, 220 and 240 Volts, 50 Hz AC,
switch-selectable,
may be switched to 60 Hz
approx. 60 Watts
9.5cm/s and 19cm/s, switch-selectable
4-track standard according to DIN 45511
for monaural and stereophonic operation
up to 18 cmdiam., according to DIN 45514
4x 120 min at 9.5 cm/s with 720 m
double-play tape and monaural operation;
playing time halved at 19 cm/s
about 5.5 min for 720 m double-play tape
1 record/playback head, G415, 1 erase
head, L315
85 kHz
85 kHz
according to DIN 45513
2xAC 150, 8x AC 122, 1x AC 124
1x AC 175, 2x AC 123, 4x AD 152P
AEG B 30 C 1200/650 K6
2x OA 150
Radio:
2x0.15mV across2 kQ
Pickup (Phono):
2x 150 mV across 2.2 MQ
Tape:
2x 150 mV across 2.2 MQ
2 x Microphone:
2x0.15mV across2 kQ
new input circuit
Radio:
2x0.15mV across5 kQ
Pickup (Phono):
2x70 mV across 2.2 MQ
Tape:
2x70 mV across 2.2 MQ
2 x Microphone:
2x0.15mV across5 kQ
Radio:
2x1.5 V across8 kQ
Earphones, mono:
0.5 V across5 kQ load
Earphones, stereo:
2x0.5 V across5 kQ load
Loudspeakers:
2x10Q (> 4Q)
Push-Pull, 2 x 6 Watts music power
40 Hz to 17 kHz for 19 cm/s
40 Hz to 14 kHz for 9.5cm/s
47dB for 19cm/s
45 dB for 9.5 cm/s
acoustic assess-
ment, measured
according to
DIN 45507
+0.2% for 19 cm/s
+0.3% for 9.5cm/s
Harmonic
Distortion Factor: <S5%
Loudspeakers: built-in, 2 loudspeakers 100 x 180 mm,
oval, may be switched off with switch-jack
Fuses: 2x0.4A medium delayed
2x 0.315 A medium delayed
Pilot Lamp: subminiature lamp 24 V / 0.08 A,
as on/off indicator
Dimensions: standing upright, width x height x depth
475 x 365 x 225 mm with lid
x 220 mm without
Weight: approx. 14kg
Special Features:
May be operated in horizontal or vertical orientation.
Completely independent controls for the two channels.
Mains Selection
The Model M 204 tape recorder may be set for alternative
Operation on 4 mains input voltages and two mains frequencies.
The voltage selector switch and the two changeover lugs for the
50/60 Hz conversion are accessible after taking off the rear panel
of the unit (3 cross-slot screws). For the 50/60 Hz conversion
it is also necessary, after taking off the control knobs and the
front panel, to place the motor belt into the appropriate groove
of the motor pulley (small diameter for 60 Hz, large diameter for
50 Hz).
Maintenance
Cleaning the Cabinet Components
To clean the handle, use ordinary commercial cleaners for plastic.
The choice wood casing should be cleaned with ordinary com-
mercial polish based on water as solvent. An anti-static substance
or device should be reapplied from time to time to the plastic
components, se that these remain dust -repellent.
Cleaning the Tape Drive Components
Regularly remove deposits of tape dust. For this purpose, pull
off the tape heads covering hood, and with a linen rag moistened
with isopropyl alcohol, clean the tape guides, the drive capstan,
the rubber pressure roller and the tape contact surfaces of the
heads. Clean the perlon-silk pressure pad on the racord/play-
back head with a small dry brush. If this pad possesses hardened
regions, it must be replaced (see hum suppression flap, replace-
ment item).
Cleaning the Drive
From time to time as well as after any repairs to the drive
mechanism, clean all drive components, the rubber brakes, the
brake surfaces of the spool plates, as well as the capstan and
the rubber pressure roller. For this purpose, use a clean linen
rag moistened with isopropyl alcohol. (Methylated spirit is less
suitable, since it is unable to dissolve molykote contaminations).

Telefunken M 204 E Specifications

General

Brand	Telefunken
Model	M 204 E
Category	Tape Deck
Language	English

Summary

Mains Selection

Maintenance

Cleaning the Cabinet Components

Instructions for cleaning the plastic and wood casing components using commercial cleaners.

Cleaning the Tape Drive Components

Guide on cleaning tape guides, drive capstan, pressure roller, and head contact surfaces.

Cleaning the Drive

Procedure for cleaning all drive components, rubber brakes, and capstan with isopropyl alcohol.

Oiling and Greasing

Demagnetisation (Degaussing)

Operating Instructions

Track Selection and Recording Procedure

How to select tracks and adjust drive levels for recording, stop, or playback modes.

Manual Controls and Connecting Jacks

Component Assemblies and Construction

Feed Plate, Switch/Jack Bracket, and Take-Up Plate Assemblies

Details of the feed plate assembly and the switch and jack bracket assembly.

Engagement Plates Mechanism

How engagement plates interact with slip plates for proper mechanism engagement.

Drive Mechanism Principles

Motor Belt Replacement

Tape Path Alignment Procedures

Feed/Take-Up Plates and Head Adjustments

Adjusting plates, erase head, and record/playback head for optimal tape path.

RP-Lever and Roller Holder Adjustment

Rubber Roller Pressure Measurement

Drive Mechanism Adjustments

Clearance Checks (FF/Rewind)

Checking clearances for intermediate wheels and engagement plates in FF/RW modes.

Friction Wheel, Slipping Clutch, Tape Tension, and Brakes

Adjusting friction wheel pressure, slipping clutches, measuring tape tension, and checking brakes.

Mechanical Adjustments and Operation

Quick Stop, Tape Speed Selector, and Capstan Bearing

Adjusting quick stop, tape speed selector mechanism, and drive capstan bearing.

Electrical Measurements and Adjustments

Head Alignment and Frequency Response Checks

Adjusting heads, checking playback response, equaliser, pre-emphasis, and frequency response.

Recording Level Adjustments

VU-Meter Calibration and Recording Levels

Calibrating VU meters and setting stereo/mono recording levels for consistent playback.

Stage and Oscillator Alignment

Output Stage and Oscillator Frequency Alignment

Aligning output stages and tuning oscillator frequency for optimal performance.

Circuit Operation Modes and Amplifier Details

Various Operation Modes and Amplifier Descriptions

Describes Parallel, Stereo, Mono, Multi-Play modes, earphones, amplifier, and output stage details.

VU-Meter Circuit Operation

Oscillator Circuit Function

End Switch-Off Mechanism