Instruction/ maintenance manual of the product DH-200 Hafler
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THE POWE R AMPLIFIER INSTRUCTIONS for OPERATION and KIT ASSEMBLY CAUTION: IF THE SPEAKER FUSES BLOW, SOME DISTORTED SOUND CAN BE HEARD. THEREFORE IF AMPLIFIER MALFUNCTIONS, ALWAYS CHECK FOR BLOWN FUSES FIRST.
INTRODUCTION The Hafler DH-220 is a two channel audio power amplifier designed to the very highest performance standards. It is available either as a kit, or fully assembled. Its 115 watt per channel power rating is sufficient for driving all loudspeakers in home applications, and its design assures extremely low distor- tion of all types.
INSTALLATION Th e DH-22 0 is most likely to be installed out of sight in most applications, since its power may be controlled by the AC switching of most audio preamplifiers, like the Hafler DH-110.
performance. Special low capacitance cables enable even greater distance between preamp and amplifier. It is desirable to keep the left and right input cables close together throughout their length to minimize the likelihood of hum pickup. Also, you should avoid running them parallel to AC cord s - these should be crossed at right angles.
A soldering “ gun ” is not recommended. The unfamiliar user is more likely to damage the etched circuit boards with its higher heat potential and unbalanced weight. Also, because he may not wait long enough for it to reach operating temperature each time it is switched on, poor solder connections are more likely.
Wiring the Kit If any components are unfamiliar to you, checking the pic- torial diagram should quickly identify them. Or, the quantities, and the process of elimination as you check the parts list, will help.
5 n Select the two round fuse holders, and two each 1/2” rub- ber washers, lockwashers and nuts. First install the rub- ber washer on the holder, so it will be outside the chassis, and then fasten the fuse holders at LF and RF, with the tip lugs pointing towards each other, toward the center of the chassis.
19 c3 Prepare a 7 ” green wire. Connect one end to terminal LB. (S-2). Place this wire towards the center of the chassis. 20 Ll Prepare a 10 ” white wire and a 10 ” green wire. Starting with the white wir e 3/4" longer, twist them together.
The transformer leads may be trimmed as desired for a neat job, but be sure you do not cut any of them too short (particularly if yours is the multi-voltage version, and any change to a different supply voltage is likely). Cutting the leads too short for re-use may void its warranty, if it is thought to be defective.
55 I 56 [ 57 : 58 : 59 I 60 : 61 1 62 ! 63 I 64 : Select the white pair of wires at the front of the chassis. Tuc k the excess-wire into the corner and connect one wire to each of the lugs on the thermal breaker.
Bias Remove th e B + fus e F2. Thi s fuse is in the line from th e ’ + ’ capacito r terminal to hol e #3 on the board. Connect an ammeter ’ s ' + ' !ead to the fuse clip nearest the large filter capacitors. Connect the ’ - ’ lead to the other side of the fuse clip.
The power transformer supplied i n DH-220 amplifiers sold in th e lJSA is intended for 120 volt, 60 Hz operation only. For use in other countries, a multi-voltage transformer is available at higher cost.
KI T PARTS LIST Minor variations may sometimes be encountered in value or appearance. These will not affect performance. Part No. Fuse Envelope 6 Fuse, 5 ampere 2 Fuse, 2 ampere 1 Fuse, 7 ampere, Slo-Blo 1 Additional fuse, 4 ampere, Slo-Blo (International use only) 1 1 2 2 1 4 2 1 2 2 1 2 2 2 1 1 1 1 1 1 1 1 1 Chassis Cover Capacitor .
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COMPONENT VALUES All resistors ar e l/4 w carbon fil m unless specified otherwise Rl 470,000 ohms R2 1,800 ohms R3 47,000 ohms R4 47,000 ohms R5 1,000 ohms R6 1,000 ohms R7 47,000 ohms R8 560 ohms R9 .
SPECIFICATIONS Power Rating: Les s than 0.02% total harmonic distortion at any power level up to 115 watts continuous average power per channel into 8 ohms at any frequency between 20 Hz and 20 kHz with both channels driven. Input Impedance: 47,OOO ohms.
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INSTRUCTIONS FOR THE HAFLER DH-222 AMPLIFIER BRIDGING KIT FOR THE DH-220 The DH-222 may be installed in a Hafler DH-220 power amplifier to enable easy conversion to a high power monophonic amplifier, bridging the two conventional chan- nels to a single floating output which can deliver in excess of 400 watts into an 8 ohm load.
DH-222 INST ALLATIO N INSTRUCTIONS 10 2cl 30 40 50 60 70 80 Disconnect AC power from the amplifier, and remove all con- necting cables. Wait 5 minutes to allow capacitors to discharge before proceeding with disassembly.
An important point after buying a device Hafler DH-200 (or even before the purchase) is to read its user manual. We should do this for several simple reasons:
If you have not bought Hafler DH-200 yet, this is a good time to familiarize yourself with the basic data on the product. First of all view first pages of the manual, you can find above. You should find there the most important technical data Hafler DH-200 - thus you can check whether the hardware meets your expectations. When delving into next pages of the user manual, Hafler DH-200 you will learn all the available features of the product, as well as information on its operation. The information that you get Hafler DH-200 will certainly help you make a decision on the purchase.
If you already are a holder of Hafler DH-200, but have not read the manual yet, you should do it for the reasons described above. You will learn then if you properly used the available features, and whether you have not made any mistakes, which can shorten the lifetime Hafler DH-200.
However, one of the most important roles played by the user manual is to help in solving problems with Hafler DH-200. Almost always you will find there Troubleshooting, which are the most frequently occurring failures and malfunctions of the device Hafler DH-200 along with tips on how to solve them. Even if you fail to solve the problem, the manual will show you a further procedure – contact to the customer service center or the nearest service center
