Advent 201 tape sm

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A DV E\ Service Manual for Model 201
Starting with Ser. No. 001001

~-» .m- an

Table of Contents

I. General Information .............. 2 III. Electrical Sectlon .............. 7
I .l Specifications ................ 2 SJ Set Up and Chassis Alignment ...... 7
1.2 Test Tapes ................. 2 3.2 Troubleshooting Guide. Signal Path . . . 9
3.3 PC Board Disassembly .......... 10
II. Mechanical Soctlon ....... . ...... 3 3.4 Voltage Chart & Board Photo ...... 12
3.5 Reassembl) ............... l 2
2.1 Disassembly ................. 3 3.6 Parts List ................ l4
2.2 Reassembly ................. 3 3-7 Block Diagram .............. l8
2.3 Troubleshooting .............. 4 3.8 SChematic ................ I9
2.4 Exploded Diagram ............. 5a

2.5 TransportPartsList. . . . . _ . . . . . . . .Sb

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I. General Information

1.1 Specifications

Speed: l.875 ips

Wow and Flutter: less than 0.l5%. DIN Weighted
High Speed Wind Times: 45 seconds for a 060

End of Tape Shut Off: Fully automatic. Disengages
pinch roller and heads from

the cassette.
35 my for 0 VU
Nominally 50.000 ohms.
Varies with settings of INPUT
and RECORD LEVEL
controls from 25.000 to
l00.000 ohms.
Output: With OUTPUT LEVEL
control at maximum. 580 my
61 200 ohms from 0 VU
tape level.

lnpul Sensitivity:
lnput Impedance:

Tape dependent. Distortion
in the electronics is typically
less than 0.l% up to and
beyond tape saturation.

'A Word About Frequency Response

Distortion:

Frequency response measurements on open reel recorders are
normally taken at a record level 20 dB below 0 VU( 20 VU) in
order to avoid tripe saturation at high frequencies. Because of the
substantial amount ofhigh frequency boost equalization required
at 1-7/8 ips in order to achieve extended high frequency response.
frequency response measurements must be taken at a record level
30 dB below 0 VU. Frequency response measurements taken at
a higher level than that will only indicate the saturation properties
of the tape being used. not the high frequency capabilities of the
recorderr (fly the way. When tape saturates. the output does not
remain constant; it actually decreases at the input signal is increased.

1.2 Test Tapes

3545.000 Hz 1 2 (ID with
Crolyn tape ((5 30 VU)
3544.000 Hz 2 2 dB with
Regular tape.

Frequency Response:

Referenced to 0 VU. Dolby
System offo

Better than 54 (ill with
Crolyn tape

Better than 48 dB with
Regular tape

Signal to Noise Ratio:

With Dolby System on.
IO dB @ 4.000 Hz and above
9 dB 6 2.400 Hz
6 dB @ l.200 Hz
3 dB (2 600 Hz

Noise Reduction:

Bias Frequency: l l0 kHz

Power Requirements: l20 Volts AC. 60 Hz. 25 watts

If you re wondering how its possible to record music when
wide band response is possible only at such low levels. rest at ease.
Music is not flat. Because there are no musical fundamentals above
approximately d kHz (and those at that frequency are rare). the
only information above that frequency is composed of musical
harmonics or overtones so that the energy in music above 4 kHz
decreases dramatically. Were this not so. the equalization so
necessary to not only tape recording, but discs and IM as well.
would not be possible. And for those few pieces of music that
do cause saturation when recorded normally. the solution it to
record at a lower level.

Listed below are the various tapes that should be used for checking and performing the adjustments to this

manual. The source for these tapes is Philips.

TYPE NUMBER DESCRIPTION PRICE
TC-AIO lOkHz azimuth tape $19.25
TC-FL3 3000 Hz flutter tape 52 l .50
TC-FL3.15 3l50 Hz flutter tape S2l.l0 meter.
TC-S 6.3 kHz 8: 800 Hz tape $17.70
TC-F R Playback frequency 595 .50

COMMENTS

Probably the one tape that every service department should have.

These tapes are useful only ifyou have a flutter

This can be used for checking speed without a drift (speed) meter.
Oflimited use for servicing although it can double as an azimuth

response (IOkHz band) tape.

A booklet giving detailed descriptions of these tapes is available from: North American Philips Corp.. Order Dept..
Home Entertainment, 100 East 42nd Street. New York. N. Y. [0017. Telephone: 212-697-3600.