Dual 1228 Service Manual

Page 1

ua

Edition July 197

Dual 1228
Service Manual

Technical data

Current typo

Lina voltage

Drive

Power consumption
Current requirements

Platter

Platter speeds

Pitch control

Spud chock

Wow and flutter
Sign-Hanoi ratio

Tone-rm
Ionearm boating friction

Pick-up head

(cartridge holder)

Stylus prawn

Pick-up cartridge

Waidtt

Mounting dimensions and
mounting board cut-out

AC 50 or 60 cycle, with appropriate motor pulleys

110/130 V and 220/240 V selector

4-pole synchronous motor

< 10 Watt

approx. 64 mA at 220 V 50 cycle

approx. 115 mA at O V 50 cycle

non-magnetic 1.8 kg (4 lb) 270 mm (10.5 mch.l diameter

33 1/3 and 45 rpm, automatic tonearm setdown caupled to speed selector

Adjustment of approx, 1 semitone (6 96) at both platter speeds

wlth light stroboscope for platter speeds of 33 1/3 and 45 rpm adjustable tor 50 or 60 Hz
< i 0.09 96 rated in accordance with DIN 45 507
Rumble si nal-to-noise ratio > 59 d8 .
Rumble ugweighted sngnal-to-noise ratio > 39 dB in accordance wnh D'N 455(1)
Torsion resistant, aluminum tonearm in universal low-point glmbal suspensnon

vertical < 0.008 0

horizontal < 0.016 p

Removable, suitable for acceptance of all cartridges havmg 1/2 mounting and a deadweight

of 2 - 8 grams (including mounting fixtures)

Continuously~adjustable from 0 - 10 p. reliable as from 0.5 p stylus pressure

see separate data sheet

4.3 kg

see installation instructions

Dual Gebrfider Steldlnger -7742 St. GeorgenlSchwarzwald

Page 2

fig. 1 Pick-up Connection Diagram

right channel left channel 4
P\ ___.-1 f' ----- I °1 '
I T-"I r. r--C -- }--1 ,-vI ' I
I } l----I ::>' red I , , 1 white I: ~ r-- I :
: r+--J t;:-- L-{ I : E I }--L--:':; L--\\ I
y ; p ' ----- T In \J
1 g E a ::I- tom-rm audio cable
F +~ _ - - 1' .'
l l
: .m-T-l :
I I
1. 3 u l J a) with mini-mo plug 51in
I
Muting switch m r
r - right channel
l red lead
I
i left channel
; § I white lead
I
I
3 E bl with phone plug
' c§::::::2::3>--r-------.
= n__,2 a
l
I
1 beck whhe
L- _____________ __--___--- ELF-1'- -J (red) (yellow)
:: II :
.' bled:

right channel
red

left channel
white

Mass right channel
green

blue

,__.._.._.._......._..__....g,
,--___---__-_---__-__--_1-

o.--...--- ----- ,--_--_-_- .

.L
I

I

l

I Mess left channel
I

I

1

l

I

l

i

|

I

I

Contact able at tonearm heed Tonarm head
Spring contacts between

plug-in cartridge
head and tonmrm

green

Cartridge

Record a
-> Inner side of groove 2 outer side of groove
left channel right channel

Page 18

Fig. 28

J

Exploded ViBU,

parts above chassis

'©

C

'51

'52

53

55

57

59

'60
'61
'62

'67

'69

70

.u

-75

'76

-78

Page 20

Duan-

Dos. Pert.-No. Description tity
0 1 225 247 Silicon diode av 103/300 ....................... 1
c 1 225 322 r611 capacitor 68 nF/400 v/10 S ................ 1
c 46 224 886 r011 capacitor 47 nr/zso u/20 % ................ 1
n 1 232 402 Carbon resistor 22 kQ/0.25 0/5 X ............... 1
R 2 232 401 Carbon resistor 12 kQ/0.25 U/S I ............... 1
77 225 321 Tubular glim lamp .............................. 1
78 233 230 Case louer part compl. ......................... 1
79 227 162 Prism .......................................... 2
100 232 439 Spring washer 6.4/11/0.15 ...................... 1
101 229 373 Adjuster uheel ................................. 1
102 210 586 Uesher 3.2/7/0.s St ............................ 1
103 210 362 Hexagon nut 8H 3 ............................... S
104 228 112 Adjusting uheel ................................ 1
105 210 182 Lock uasher, thr. .............................. 1
106 228 113 Uasher a.2/a/1.0 St ............................ 1
107 210 146 Lock uasher 3.2 ................................ 2
108 229 370 Selector segment ............................... 1
109 229 714 Compression spring ............................. 1
110 229 663 Bracket compl. ................................. 1
111 210 472 Filliater head cap acreu AM 3 x 4 .............. 2
112 229 715 Bearing spindle ................................ 1
113 232 900 notor pulley 50 Hz compl. ...................... 1
232 901 Motor pulley 60 Hz compl. ...................... 1

114 230 559 Set screw 0 2.5 x 3.5 .......................... 1
115 210 366 Hexagon not an 4 ............................... 3
116 229 027 Screen plate ................................... 1
117 233 038 Top bearing bracket complete ................... 1
118 209 939 Cable grommet .................................. 1
119 233 086 Stator 110/220 0 compl. ........................ 1
120 233 084 Rotor compl. ................................... 1
121 233 039 Bottom bearing bracket compl. .................. 1
122 228 472 Centering screu ................................ 2
123 233 087 4-pole motor SM 400 110 - 220 V complete ..... 1
124 229 374 Regulator uheel ................................ 1
125 229 695 Regulator plate ................................ 1
126 229 372 Adjustment uasher .............................. 1
127 210 600 Uesher 3.2/e/1 s: .............................. 1
128 229 716 Compression spring ............................. 1
129 210 146 Lockuaaher 3.2 ................................. 2
130 229 672 Change lever ................................... 1
131 223 625 Lockueeher 3 ................................... 1
132 233 012 Suitch plate compl. ............................ 1
233 013 Snitch plate UL with special capacitor compl. .. 1

133 230 151 Slide .......................................... 1
134 209 505 Capacitor 10 nF/1000 9/10 X .................... 1
230 355 Capacitor ea nF/ 250 u/20 X .................... 1

135 230 148 Switch slide ................................... 1
136 230 296 Tension spring ................................. 1
137 219 200 Snap spring .................................... 1
138 233 010 Cover normal compl. ............................ 1
233 011 Cover UL compl. (for KS 4 with connection plate) 1

139 210 498 Fillister heed cap screu H 3 x 28 .............. 1
140 233 009 Pouer snitch compl. ............................ 1
233 008 Pouer eultch UL uith special capacitor compl. .. 1

141 233 007 Connection plate compl. ........................ 1
142 233 005 Connection plate compl. uith cover ............. 1
143 233 006 Connection plate cover compl. .................. 1
144 210 501 Fillister head cap ocreu fl 3 x 35 .............. 1
145 229 748 Screen plate ................................... 1
146 232 987 Huting suitch compl. ........................... 1
147 211 614 Soldering lug .................................. 1
148 210 469 Fillieter heed cap screu AM 3 x 3 .............. 2
149 200 633 Lock washer .................................... 1
150 217 888 Idler wheel compl. ............................. 1
151 229 719 Slip plate ..................................... 1
152 229 747 Suinging arm compl. ............................ 1
153 210 362 Hexagon nut BM 3 ............................... 5
154 233 089 Screen plate compl. uith insulating plate ...... 1
155 210 155 Serrated lockuesher A 3.2 ...................... 2
156 227 254 Cynch socket plate ............................. 1
157 210 144 Lockuasher ..................................... 1
158 229 635 Shut-off lever ................................. 1
159 229 756 Friction plate ................................. 1
160 210 145 Lockuaaher 2.3 ................................. 7
161 232 988 Main can complete .............................. 1
162 210 145 Lock washer 2.3 ................................ 7