INSTRUCTIONS FOR
THE HAFLER DH-502 AMPLIFIER BRIDGING KIT
FOR THE DH-500
The DH-502 Amplifier Bridging Kit for the DH-500 consists
of a PC-7A circuit board comprising a 6 transistor phase inverting
amplifler, a mounting bracket, necessary hardwareandconnecting
wire. Installation may take about an hour. All changes to the
amplifier wiring are performed on the right channel - the side
nearest the power switch. Only the left channel input will be utilized
after conversion so an additional pair of input wires will be
connected to that jack to enabie it to feed the complete amplifier.
When converted to monophonic operation, the loudspeaker
load is t o be connected to the t w o centerred (+) outputs only. The
right (+) will act as the common and should be attached to the
speaker (-)_ This is what is known as a floating output, for no
connection is made to either black ground terminal. It is sug-
gested that once the amplifier has been converted, some clear
indication be made as to the appropriate connections, and that be
attched to the back panel. Because of this floating output, neither
side of the output signal may be grounded; such as thru a speaker
switching box or head phone adapter that has a common ground
between the left and right channels.
For equivalent load impedances, the speaker fuses provide the
same power output protection as in stereo operation, but because
of individual
fuse variations,
only one fuse may blow at these
levels. It is best to replace both fuses if one blows, as the other
may have been weakened.
These installation instructions designate connections in ac-
cordance with the DH-500 owner’s manual and pictorial diagram,
and use the same terminology (i.e. “S” indicates a soldcrcd
connection),
KIT PARTS LIST
1
PC-7 Board
WP-PC7
1 M
ounting bracket
SM-BRT202*
2
Screw, Machine, 4-40 x 5/16”
HWH-145
2 Nut. 4-40 KEP
HWH-105
1
Wire Red #20 GA 3.0’
I
Wire, Green #20 GA
3.0’
1
Warranty
Card
LIT-WAR
T O
LIMITED WARRANTY
The
parts
in the
DH-502 are
warranteed for a full year from the purchasedateincluding
parts
and labor. If a defective componcnr is found on a circuit board
or in the kit, simply return
the individual
part, or if the problem is unknown, retumthedefcctive board to
the
factory,
prepaid, together with the serial number
and a
copy
of the
dated bill of sale, and it wil be repaired or replaced at no charge. This warranty is limited to repair or replacement of the DH-502 bridging
module only. Hafler is not responsible for consequential damages. This warranty gives you specific legal rights. You may also have other rights which
vary from state lo state.
This warranty is void if acid core solder or paste flux has been used.
A Division Of Rockford Corporation
613 S. Rockford Drive, Tempe, Arizona 85281
l
(602) 967-3565
