Heathkit HP 23A Manual

Page 2

Assembly
and

Operation
of the

,37
11 szlK'l 1(1'

AC POWER SUPPLY

MODEL HP-23A

TABLE OF CWTENTS

Step-By-Step Assembly

Chassis Wiring. . . . . . .
Component Installation. . .
Final Wiring. . . . . . . ..
Final Assembly. . . . . . .
Initial Tests. . . . . . . .....
Operation. . . . . . . .
In Case 0! Difficulty. . . . . . .
Troubleshooting Chart. . . . . .

Specifications. . . . . . . . . . . .

trompage)...........

HEATH COMPANY
BENTON HARBOR, MICHIGAN 49022

Introduction...................

Parts List. .................

Chassis Parts Mounting. . . . . . .
Transformer Wiring. . . . . . . .

Schematic (fold-out from page). . .

Factory Repair Service. . .(fold-out

Circuit Description. . . . . . . .....

Chassis Photograph. . . . . . . . . . .

. .

Replacement Parts Price List. . . . .

w

~om-I-aa

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( ) Connect the power cable from the Power
Supply to your equipment.

( ) Connect the line cord plug to an electrical
outlet supplying the voltage for which the
Power Supply was wired (120 VAC or 240
VAC).

( ) Select the desired low 8+ voltagebymoving
the AC OFF switch tothe right for 350 VDC,
or to the left for 275VDC.Hyour equipment
does not have provisions for remote control
of the Power Supply. this will turn the Power
Supply 0N. (Plate and filament voltages are
always turned on and off simultaneously.)

( ) If your equipment hasprovisionslor remote
control of the Power Supply, turn the equip-
ment off-on switch to ON.

( ) if you are using the adjustable bias, adjust
the bias voltage as necessary with the BIAS
ADJUST control.

( ) The Power Supply may be turned off by the
AC OFF switch onthe chassis, or by the off-
on switch on your equipment, provided that
it was wired for remote control.

IN CASE OF DIFFICULTY

This section of the Manual is divided into two
parts. The first part, titled General Trouble-
shooting lniormation. describes what to do about
any difficulties that may occur right after the
Power Supply is assembled.

The second part, 2 Troubleshooting ChartI is
provided to assist in servicing if the General In-
formation does not clear up the problem, or if
difficulties occur after the Power Supply has been
in operation for some time. This Chart lists some
difficulties which could arise, and severalpossi-
ble causes.

GENERAL TROUBLESHOOTING INFORMATION

1. Recheck the wiring. Trace each leadincol-
ored pencil on the Pictorial as it is checked.
it is frequently helpful to have airiend check
your work. Someone who is not familiar with
the unit may notice something consistently
overlooked by the builder.

2. About 90% of the kits that are returned to
Heath Company for repair do not function
properly due to poor connections and solder-
ing. Therefore, many troubles canbe elimi-
nated by reheating all connections to make
sure that they are soldered as described in
the soldering section of the Kit Builders
Guide.

3. Check the values of the parts. Be sure that
the proper part has been wired intothe cir-
cuit, as shown in the Pictorial diagrams and
as called out in the wiring instructions.

4. Check for bits of solder, wire ends or other
foreign matter which may be lodged in the
wiring.

5. If, after careful checks the trouble is still not
located, check voltage readings against
those on the Schematic. NOTE: All voltage
readings were taken with an ll megohm input
voltmeter. Voltages shown are with no load
on the output.

6. A review of the Circuit Description, and a
study of the Schematic Diagram will help you
locate a difficulty in the Power Supply.

'1. Check for loose hardware. Be especially
careful that metal capacitor mounting wa-
fers and terminal strip mounting feet are
well grounded.

NOTE: lnan extreme case where you are unable
to resolve a diificulty, refer to the Service and
Warranty sections of the "Kit Builders Guide",
and to the "Factory Repair Service" information
on the fold-out from Page 28 of this Manual.