Manuale d’uso / di manutenzione del prodotto DH-200 del fabbricante 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.
Un punto importante, dopo l’acquisto del dispositivo (o anche prima di acquisto) è quello di leggere il manuale. Dobbiamo farlo per diversi motivi semplici:
Se non hai ancora comprato il Hafler DH-200 è un buon momento per familiarizzare con i dati di base del prodotto. Prime consultare le pagine iniziali del manuale d’uso, che si trova al di sopra. Dovresti trovare lì i dati tecnici più importanti del Hafler DH-200 - in questo modo è possibile verificare se l’apparecchio soddisfa le tue esigenze. Esplorando le pagine segenti del manuali d’uso Hafler DH-200 imparerai tutte le caratteristiche del prodotto e le informazioni sul suo funzionamento. Le informazioni sul Hafler DH-200 ti aiuteranno sicuramente a prendere una decisione relativa all’acquisto.
In una situazione in cui hai già il Hafler DH-200, ma non hai ancora letto il manuale d’uso, dovresti farlo per le ragioni sopra descritte. Saprai quindi se hai correttamente usato le funzioni disponibili, e se hai commesso errori che possono ridurre la durata di vita del Hafler DH-200.
Tuttavia, uno dei ruoli più importanti per l’utente svolti dal manuale d’uso è quello di aiutare a risolvere i problemi con il Hafler DH-200. Quasi sempre, ci troverai Troubleshooting, cioè i guasti più frequenti e malfunzionamenti del dispositivo Hafler DH-200 insieme con le istruzioni su come risolverli. Anche se non si riesci a risolvere il problema, il manuale d’uso ti mostrerà il percorso di ulteriori procedimenti – il contatto con il centro servizio clienti o il servizio più vicino.