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- DH-110
- Instructions For Assembly And Operation Manual
Hafler DH-110 Instructions For Assembly And Operation Manual
Summary of DH-110
Page 1
The preamplifier dh-110 instructions for assembly and operation lm132 $3.00 please refer to this serial number in all communications regarding this equipment. The david hafler company 5910 crescent boulevard, pennsauken, new jersey 08109.
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Specifications the numbers in parentheses refer to the paragraph in the ihf specifications manual which defines the test procedure. 2 phono preamp section rated output: 3 8 hz-105 khz maximum output (3.5): 12 vrms, 20 hz-20 khz at recording output total harmonic distortion: less than 0.0006% @ 1 khz...
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Introduction your preamplifier is the control center of your music system, acting as an interface between the sound sources-record players, tape recorders, fm and video tuners-and the power amplifier which drives the loudspeakers. As the focal point of your system, it should be attractive and easy t...
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The dh-110 is provided with accessory rack mount end caps in addition to the standard end caps installed on the unit. These accessory caps extend the width of the front panel to that of a standard 19” rack, with appropriate mounting holes. Installation instructions are detailed later in this manual ...
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Fects that can result from unpowered electronic circuits in the tape decks when they are connected to the recording outputs, it is recommended that tape recorders be switched on when the preamplifier is in use. This is a commonly overlooked cause of less-than-ideal preamplifier performance. Signals ...
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The following controls affect all signals which are heard through speakers or headphones. They have no effect on the signals to the recording outputs. Mono switch when this button is in, left and right channel informa- tion is combined, and the composite signal is fed to both left and right outputs....
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There are three basic rules for success in electronic kit building: 1: read the instructions carefully, and follow them in or- der. 2. Make secure solder connections which are bright and smooth. 3. Check your work carefully after each step. The dh-110 preamplifier is a versatile component with sophi...
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Excess solder may be removed from a connection by heat- ing it and allowing the solder to flow onto the iron, which is then wiped on the sponge. All solder used must be rosin core never use acid core solder or any separate flux in elec- tronic work. Silver solder is also not suitable. If in doubt ab...
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Building the kit partial mechanical assembly of the kit provides protec- tion for major components during shipment. Most of the hardware thus used is included in the quantities listed in the parts list. The exception is that used to install the rear mounting bracket on the pc-14, as this is consider...
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Each socket, the board is marked to indicate the side of the hole on which the center mounting tab should be positioned, so that it will be soldered to the widest part of the circuitry on the back side. Leave the phono plug in the socket while bending and soldering is completed. If you do not bend t...
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23 select the 6 black 5/8" screws, the 6 spacers, and 6 small nuts. Insert the screws from the outside of the back panel at the locations nearer the center of the panel (not in the end holes marked “grounds”). Install a spacer on each screw and tighten them. Place the pc-12 assembly in position so t...
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0 right n n phono left , i ’ i selector monitor tone phono k s 3 flat r o u n d d13 d14.
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Ht 0109 left line 0107 c21 cl9 i - m l - 0 c34 0 c36 c32 i volume l r26.
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Wire to hole q, which is between the center lugs of jll and 512. (s). The wire should not protrude sig- nificantly beyond the front surface of the board to avoid coming in contact with a connector. To assure a good solder connection, bare wire should be visi- ble on the circuit side of the board. Co...
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If a problem arises if neither led lights when you first turn on the power switch, turn the unit off immediately. Check the fuse. Check the polarity of the leds. Check the power transformer wiring for proper connections for your line voltage. Look for a short caused by a stray strand of wire, or for...
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Additional information rack mount end cap installation every dh-110 is supplied with front panel accessory end caps which adapt it to a standard 19” rack panel, and with a 5/32” allen wrench which fits the mounting screws. Remove all power and signal connections from the dh- 110. On a protected surf...
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Minimizing noise in the system your choice of separate components is the right way to secure the best performance from a music system, but the wide-band characteristics and complexity of the best sys- tems may also not conceal the introduction of ground loops and noise pickup-especially rfi (radio f...
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Tape 2 l a w cd/video phono 1 phono 2 tuner record out epl send epl phono 1 c 2 c tone filter epl treble bass v o l 0 0 line to right channel switched direct functional block diagram 1 8.
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Component values all resistors are 1/4 watt i% metal film unless otherwise noted. Rii channel corresponding values have designations above 100. R i r2 r 3 r 4 r.5 r 6 r7 r8 r 9 rio ri1 ri2 ri3 ri4 rl5 r16 ri7 ri8 ri9 r20 r2l r22 r23 r 2 4 r25 r 2 6 r 2 7 r30 r3l r 3 2 r 3 3 r 3 4 r 3 5 r36 r 3 7 r 3...
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Cable pin numbers tuner tape 1 epl send i i i ‘i i direct output output via phone jack phono 1 phono 2 g r o u n d phone jack r 2 4 twisted l i black switch pins seen from bottom of circuit card note: shown for for other at accessory outlets b . 4 0 1 2 3 4 5 6 1 6 2 3 4 5 2 3 4 1 2 3 4 3 0 0 0 0 0 ...
Page 21: Dh 110 Preamplifier
Pc13 c29 line amplifier r 4 9 symbols p o w e r s u p p l y g r o u n d shield ground l e f t , channel signal ground r i g h t 1 power supply rails circuit card land chassis ground m a l e c o n n e c t o r p i n female connector sleeve clockwise, depressed l muting j j dh 110 preamplifier schemati...
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Kit parts list minor variations may sometimes be encountered in value or appearance. These will not affect performance. Some items may have been used to package the kit for s h i p m e n t . I 1 i 1 1 2 1 1 1 1 2 1 2 2 4 10 6 4 3 2 2 6 6 2 6 4 12 8 2 3 4 1 4 i 1 1 6 2 4 1 1 3 1 4 1 i 1 22 cover, bla...
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Service policy and limited warranty your dh-110 preamplifier has been carefully engineered to provide many years of use without maintenance or ser- vice. Factory assembled units undergo many physical and electrical tests before shipment. The circuit board in kits is similarly tested to meet all prim...
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Printed in usa.