Hadcock GH 228 User manual

GH 228 Tonearm

SPECIFICATION
Mounting hole 15.87mm dia (5/8”dia)
Overall length 307.34mm (12.10”)
Height 43mm - 90mm (1.7” - 3.5”)
Pivot stem length 86.4mm (3.4”)
Pivot to stylus length 228.6mm (9.0”)
Pivot to centre of turntable 212.85mm (8.38”)
Offset angle 23°
Rear overhang 60.9mm (2.4”)
Headshell mounting 12.7mm (0.50”)
Cartridge mass 3 -12 gms
BOX CONTENTS
Top arm tube complete with headshell and top pivot assembly
Arm base with unilift assembled with captive arm lead
Ground lead
Main weight
Rider weight
Bias weight
Bias weight pulley assembly
3 Allen Keys
Cartridge mounting screws
Mounting template
Alignment protractor
Guarantee card

Fitting instructions

1 ARM BASE ASSEMBLY
Use Mounting Template to determine position of the threaded flange (22) on the
arm mounting of the board of the turntable. Having placed the template over the
turntable spindle mark the pivot centre with a large needle in an arc, making sure
there is sufficient clearance all the way round.
Drill a 5/8” (16mm) diameter hole in the position marked. If BULLET PHONO PLUGS
are fitted to the PHONO LEADS it will be necessary to drill a 3/4” (19mm) diameter hole.
The arm base assembly should be mounted on the armboard with the WASHER (25)
and the NUT (24) which are slotted so they can easily be placed over the cable.
The THREADED FLANGE (22) should be positioned so that the SET SCREW (29)
in the flange is facing the front, thereby enabling the PIVOT PILLAR (21) to be
adjusted for height with the 1/16” ALLEN KEY.
2 BIAS PULLEY WHEEL ASSEMBLY
Undo the SOCKET CAP SCREW (15) with the ALLEN KEY (2mm) and fit the PULLEY
WHEEL ARM with the SPACER (14) and refit to the PIVOT PILLAR (21). See Fig 2.
3 FITTING THE CARTRIDGE TO THE HEADSHELL
Slacken the SET SCREW (5) in the HEADSHELL (1) with the 1/8” ALLEN KEY. The HEADSHELL
may be removed from the ARM TUBE to make it easier to fit. Make sure the cartridge
stylus is in position before fitting it to the HEADSHELL. Select screws of suitable length
and fit the cartridge to the HEADSHELL. Please note the HEADSHELL can be supplied
with plain fixing holes so that screws and nuts supplied by the cartridge
manufacturer may be used.

4 FITTING THE HEADSHELL TO THE ARM TUBE
Attach the HEADSHELL to the ARM TUBE and tighten the SET SCREW (5) near
the end of the tube. Carefully push the wires through the HEADSHELL and attach
the CARTRIDGE TAGS to the cartridge pins as follows:
RED = RIGHT LIVE
GREEN = RIGHT GROUND
WHITE/YELLOW = LEFT LIVE
BLUE/BLACK = LEFT GROUND
Do not solder direct to the cartridge pins!
5 FITTING WEIGHTS TO THE WEIGHT SUPPORT
The MAIN WEIGHT (11) and the RIDER WEIGHT (7) can now be fitted to the
WEIGHT SUPPORT (8). Position the MAIN WEIGHT (11) about half way along
to WEIGHT SUPPORT (8) AS SHOWN IN FIG.1 with the RIDER WEIGHT to the
end of the WEIGHT SUPPORT (8).
6 TOP ARM ASSEMBLY TO BASE ASSEMBLY
The whole top arm assembly can now be positioned onto the base assembly locating
the BEARING HOUSING (3) bearing onto the PIVOT PIN (20) in PIVOT PILLAR (21).
Loosen SET SCREW (17) with the smallest ALLEN KEY (0.050”) and then adjust the
ARM TUBE (2) in the BEARING HOUSING (3) SO THAT THE RED PLUG (31) wires exit
the ARM TUBE facing downwards. Make sure that when the RED PLUG is attached to
the red socket in the LIFT PLATFORM (12) the lead wires face the turntable spindle.
7 HEADSHELL ADJUSTMENT
Place the ALIGNMENT PROTRACTOR over the turntable spindle and adjust the HEADSHELL
(1) by slackening the SET SCREW (5) of the headshell along the arm tube until the cartridge
is parallel with the lines when the stylus rests at points A and B. Ensure that the top face
of the HEADSHELL is set level with the top face of the BEARING HOUSING (3).

8 ARM HEIGHT ADJUSTMENT
With the 1/16” ALLEN KEY slacken the set screw (29) in the ARM BASE FLANGE (22)
and raise or lower the PIVOT SUPPORT (21) so that the ARM TUBE is parallel with the
record on the turntable platter.
The Cartridge manufacturer’s recommended Vertical Tracking Angle (VTA) can then
be set by slackening the SET SCREW (29) and adjusting the height accordingly.
9 ADJUSTMENT OF THE UNI-LIFT
Adjust the ARM REST (9) with the 1/16” ALLEN KEY so there is clearance
when the stylus is resting on the record.
10 BIAS WEIGHT ADJUSTMENT
The BIAS THREAD LOOP should be attached to the BIAS ROD (19) between the plastic
spacers. The BIAS PULLEY WHEEL ARM (16) should be set so that the thread is parallel
with the ARM TUBE when the stylus is resting on the record. See Fig. 3.
It is recommended that the position of the BIAS THREAD LOOP between the spacers
on the BIAS ROD (19) should initially be halfway along the rod. The final position of
the BIAS THREAD LOOP should be determined by using the Hi-Fi News Test Record.
Set the MAIN WEIGHT (11) and the RIDER WEIGHT (7) to the cartridge manufacturer’s
recommended tracking force. It is essential to use a Stylus Balance Gauge to achieve
accurate pressure. Azimuth (i.e. the angle of the HEADSHELL) is adjusted and can be
set by rotating the MAIN WEIGHT (11).

C&C Hadcock Audio Division
The Watermark
Ribbleton Lane
Preston
Lancashire UK
PR1 5EZ