Operation Manual Public Address Amplifier PAM-120A/340A/480A
PUBLIC ADDRESS AMPLIFIER Welcome A personal welcome to you from the management and employees of Inter-M All of the co-workers here at Inter-M are dedicated to providing excellent products with inherently good value, and we are delighted you have purchased one of our products. We sincerely trust this product will provide years of satisfactory service, but if anything is not to your complete satisfaction, we will endeavor to make things right.
PUBLIC ADDRESS AMPLIFIER Contents Unpacking .......................................................................................................................................2 Installation Environment....................................................................................................................................2 Important Safety Instructions.............................................................................................................2 Features.......................
PUBLIC ADDRESS AMPLIFIER Unpacking Although your PAM-120A or PAM-340A or PAM-480A is neither complicated nor difficult to operate, we recommend you take a few minutes to read this brief manual and familiarize yourself with the important information regarding product features, setup and operation. As with most electronic devices, we strongly recommend you retain the original packaging.
PUBLIC ADDRESS AMPLIFIER Features - MODULAR DESIGN Optional modules can be installed in multiple configurations for convenience and ease of use. Choose the PAM-CDA (Compact Disc), PAM-T (AM/FM Tuner) or PAM-D (Cassette Deck) modules to expand the PAM-120A/340A/480A’s audio capabilities. - INDIVIDUAL INPUT GAIN CONTROLS Rear-panel gain controls for each input channel for total control of individual levels.
PUBLIC ADDRESS AMPLIFIER Front Panel 1. TUNER MODULE BAY This panel provides for installation of optional PAM-T (AM/FM Tuner) Module, via the unit’s internal connectors. 2. CASSETTE DECK AND CD MODULE BAY This panel provides for installation of optional PAM-CDA (CD Player) or PAM-D (Cassette Deck) Modules, via the unit’s internal connectors. 3. OUTPUT LEVEL DISPLAY This seven-segment LED meter indicates the amplifier’s output level in RMS. 4.
PUBLIC ADDRESS AMPLIFIER Rear Panel (PAM-120A) 1. SPEAKER OUTPUT TERMINAL STRIP Connect up to five individual speakers to this strip. Impedances for 4Ω, 70V and 100V operation are shown below. Connect speakers whose combined impedance is equal to or higher than the rated output impedance, as shown below. 2. IMPEDANCE SELECTOR Selects between high impedance operation at 70V or 100V distributed systems. Note that when speakers are connected to the 4Ω terminal, this switch is inactive.
PUBLIC ADDRESS AMPLIFIER 6. PRIORITY SWITCH When selected, these switches will give priority to Channels 1 and/or 2 over all other channels and audio inputs. 7. AC POWER INPUT Connect a standard three-pin AC cable your AC outlet. 8. EXT CHIME When these two terminals are shorted, the four-tone chime circuitry is activated. 9. EXT MUTE When these two terminals are shorted by wired remote, signals from Input Channels 3-6 and any optional modules are muted.
PUBLIC ADDRESS AMPLIFIER Rear Panel (PAM-340A/480A) 1. SPEAKER OUTPUT TERMINAL STRIP Connect up to five individual speakers to this strip. Impedances for 100V operation are shown below. Connect speakers whose combined impedance is equal to or higher than the rated output impedance, as shown below. MODEL 100V PAM-340A 29.4Ω PAM-480A 20.8Ω 2. ANTENNA CONNECTOR (OPTIONAL) This terminal is used to connect the antenna, when used with the optional PAM-T AM/FM Tuner module. 3.
PUBLIC ADDRESS AMPLIFIER 5. PRIORITY SWITCH When selected, these switches will give priority to Channels 1 and/or 2 over all other channels and audio inputs. 6. AC POWER INPUT Connect a standard three-pin AC cable to your AC outlet. 7. EM When EM switch is connected and pressed in fire or other emergencies, EM broadcasting stored in VOICE IC is outputted.
PUBLIC ADDRESS AMPLIFIER 14. CHANNEL INPUTS 1-6 These balanced three-pin XLR connectors accept a standard microphone cable or other low impedance signal. Optional transformer balanced inputs are also available. 15. INPUT GAIN CONTROLS These knobs provide continuous control of the input levels for each of the six input channels. When adjusting the input gain, make certain that the levels are not set too high, or distortion will result.
PUBLIC ADDRESS AMPLIFIER Connecting Speakers Before connecting speakers, disconnect the AC power cable. Note the proper connecting terminals as shown below. Make certain that the total impedance is not less than the rated impedance indicated. CONNECTING 4Ω OR 8Ω SPEAKER SYSTEMS (only PAM-120A) When connecting conventional 4Ω or 8Ω speaker systems, connect the speaker’s positive (+) side to the terminal labeled 4. Connect the speaker’s negative (–) side to the terminal labeled COM.
PUBLIC ADDRESS AMPLIFIER For example, if you are connecting speakers with a rated input of 15W, you can connect up to 8 speakers in parallel, as shown below: 15Wx8 units(120W(PAM-120A)) WARNING: Extreme care must be exercised when connecting low-impedance systems, as potentially hazardous voltages may be present at these terminals. Do not install this equipment in a confined space with less-than-adequate ventilation.
PUBLIC ADDRESS AMPLIFIER Applications PAM-120A 12 PAM-120A/340A/480A
PUBLIC ADDRESS AMPLIFIER PAM-340A/480A PAM-120A/340A/480A 13
PUBLIC ADDRESS AMPLIFIER Block Diagrams PAM-120A 14 PAM-120A/340A/480A
PUBLIC ADDRESS AMPLIFIER PAM-340A/480A PAM-120A/340A/480A 15
PUBLIC ADDRESS AMPLIFIER Specifications PAM-120A PAM-340A PAM-480A Rated Output Power 120W (RMS):THD 1% 340W (RMS):THD 3% 480W (RMS):THD 3% Frequency Amp In 80Hz~20kHz Response Link In 80Hz~15kHz CH1~CH6 120Hz~8kHz Remote In 120Hz~8kHz 120Hz~8kHz T.H.D.(at 1kHz Rated Output) Less than 1% T.H.D.
PUBLIC ADDRESS AMPLIFIER Service Procedures Take steps to insure the problem is not related to operator error or other products within the system. Information provided in the troubleshooting portion of this manual may help with this process. Once it is certain that the problem is related to the product contact your warranty provider as described in the warranty section of this manual. Schematic A Schematic is available by contacting your warranty provider.
Inter-M, Ltd. (Korea) began operations in 1983. Since then, Inter-M has grown to become one of the largest manufacturers of professional audio and commercial sound electronics equipment in the world. Inter-M has gained worldwide recognition for its own branded products, as well as private label manufacturing of electronics sold under other names (OEM).