-
Radio Shack 811081640B - page 1
Owner’s Manual Please read before using this equ ipment. MPA-40 20-Watt PA Amplifier 32-2001.fm Page 1 Friday, February 4, 2000 7:53 AM ...
-
Radio Shack 811081640B - page 2
2 ˆ Contents Features ......... ................ ................ ................ ................. ................ ................ ......... 3 Preparation ....... ................ ................ ............. ................. ................ ................ ......... 4 Presetting th e Controls ................ ................. .......... ...
-
Radio Shack 811081640B - page 3
3 ˆ Features Your RadioShack 20-Watt PA Amplifier gives you 20 watts of solid power for your PA system. Its wide frequen cy re- sponse easily handles amplification of voice and music. It operates on eithe r 120 volts AC or 12 volts DC power so you can use it anywhere you want to de- liver special announcement s or pl ay mu- sic with great sound. I ...
-
Radio Shack 811081640B - page 4
4 ˆ Preparation PRESETTING THE CONTROLS Warning: A sudde n high out put from the amplifier could dama ge your hearing or the speakers conn ected to the amplifi- er’s output. To avoid accidentally overdr iving a channel or premat urely amplifying an audio input, se t all the amplifier’s front- panel controls to their lowest set tings. To avoid ...
-
Radio Shack 811081640B - page 5
5 PHONO/AUX/CD Switch — s elect the input source. Even if you connected auxiliary equipment to both the PHONO and AUX/CD input jacks, you can use only one so urce at a time . Speaker Push Termina ls — press the appropriat e tab to open a ter minal. In- sert the end of a spea ker wire into the opening, then rele ase the tab to close the termina ...
-
Radio Shack 811081640B - page 6
6 3. T ouch the positive end of a 1 .5-volt flashlight batt ery to the speake r ter- minal that does no t have the wire attached to it. 4. T ouch the negative end of the bat- tery with the lose end of the wire attached to the other speak er termi- nal. Note the direc tion of the cone movement — inward or outward. 5. If the spea ker cone moves out ...
-
Radio Shack 811081640B - page 7
7 • If you connect more t han two speak- ers using only se ries or only parallel connections, t he total impedance might exceed the am plifier ’s maxi- mum impedance (1 6 ohms) or fall below its minim um impedan ce (4 ohms). For example, if y ou connect fo ur 8- ohm speakers: –In series, the tota l impedance is 32 ohms (8 + 8 + 8 + 8 = 32). T ...
-
Radio Shack 811081640B - page 8
8 you can make the correct connecti on. The total impedance of all the speakers must match one of the amplifier’s out put terminals ( 4 Ω , 8 Ω , or 16 Ω ) . Speakers in Series 1. T o determine the total impeda nce of speakers connecte d in series, add the impeda nce of all the speakers. For example, if you want to co nnect two 8-ohm spea k ...
-
Radio Shack 811081640B - page 9
9 If you connect fou r 8-ohm speaker s in series, the total imp edance is 32 ohms (8 + 8 + 8 + 8 = 32). This exceeds the maximum rating. If you connect th ese speakers in paral- lel, the total impeda nce is 2 ohms (8 ÷ 4 = 2). This falls below the minimum rat- ing. You can arrive at a pro per total imped- ance by combining series and parallel conn ...
-
Radio Shack 811081640B - page 10
10 You need a separa te transformer for each spea ker. Line transformer s have several connec- tors called taps. The primary t aps (on one side o f the transformer) a re the inputs an d are rate d in watts. The secondary taps (on the op - posite side of t he transforme r) are the outputs and ar e ra te d in oh m s. Cautions: • Before you connect ...
-
Radio Shack 811081640B - page 11
11 3. Connect a wire fr om the speaker ’s positive (+) terminal t o the trans- former’s secondary tap that matches the speaker ’s total imped- ance (4, 8, or 16 oh ms). 4. Connect a wire from the speaker ’s negative (–) te rminal to the COM tap on the transfor mer ’s seco ndary side. ˆ Controls and Operation MICROPHONE 1 and 2 Inputs ? ...
-
Radio Shack 811081640B - page 12
12 ˆ T roubleshooting If you should ru n into difficulties, che ck the wiring of the system. Are the re any short circuits in th e speaker wirin g? Have you provided adequate ventila - tion? Did you calculate speaker imped- ance corr ectly? Be sure microphon es and connecting cables are not defective. Be sure you ar e using large enoug h speaker w ...
-
Radio Shack 811081640B - page 13
13 ˆ Care and Maintenance To enjoy yo ur amplifie r for a lon g time: • Keep the a mplifier dry . If it get s wet, wipe it dry immediately . • Use and store the amplifier only in normal tem perature environments. • Han dle the amplifier gently and carefully . Don’t drop it. • Keep the amplifier away from dust and dirt. • Wipe the ampli ...
-
Radio Shack 811081640B - page 14
14 ˆ Specifications Output Power at 1 kHz, 10% THD ................. ................ .............. ................. .............. . 20 W atts THD at 1W , 1 kHz Low-Pass Filter MIC1 .......... .............. .............. .............. .............. .............. .............. .............. .............. .... 1% MIC2 .......... ......... ...
-
Radio Shack 811081640B - page 15
15 ˆ Notes 32-2001.fm Page 15 Friday, February 4, 2000 7:53 AM ...
-
Radio Shack 811081640B - page 16
32-2001 81 10816 40B 02A00 Printed in China RadioShack A Division of Ta ndy Corporation Fort Worth, Texas 76102 Limited One-Y ear Warranty This product is warranted by RadioShack against manufactu ring defects in material and workman- ship under normal use for one (1 ) year from t he da te of pu rchase from Radi oSha ck compan y- owned stores and a ...
¿Tienes una pregunta acerca de Radio Shack 811081640B?
Utiliza el formulario que se encuentra abajo
Si con la ayuda del manual de instrucciones encontrado no has podido solucionar tu problema con Radio Shack 811081640B, haz una pregunta utilizando el formulario que se encuentra abajo. Si alguno de los usuarios ha tenido un problema parecido con Radio Shack 811081640B probablemente compartirá una forma de solucionarlo.