Fisher MPX 100 Owners Manual

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THE FISHER MPX-100 UNIVERSAL Stereophonic Multiplex Adaptor L T HE FISHER MPX-100 is designed to adapt your FM-AM or FM tuner to receive multiplex broadcasts in full stereophonic sound. The experience gained from years of leadership in the design and manufacture of FM tuners has been applied to the design of the MPX-100 and has made it the best performing and most convenient multiplex adaptor 111 existence. The exclusive FISHER STEREO BEACON is a~~tontatically illuminated when you tune to a multiplex program and turns off as soon as the station reverts to ordinary mono- phonic transmission. At the same time, the FISHER Automatic Switch- ing System senses whether the program transmitted is stereo or mono- phonic and switches the MPX-100 into the proper operating mode, thus making it unnecessary to switch back and forth between stereo and mono on your adaptor. Feedthrough connections for all types of tuners arc provided, even when the MPX-100 is turned off. Two separate noi~c filters can be operated by a single front panel sw~tch. One filter oiTectb: the noise in the subcarrier only, thus providing full frequency I rewpoose; the other filter is designed to provide a steep roll-off al~ove 8 kc lor reception of multiplex signals under more difficult conditions. Most important of all are the careful attention to every detail of manu- facture and the top-quality parts which have given FISHER products r a world-wide reputation for remarkable durability and outstanding reliability. INITIAL ADJUSTMENTS 11 FISHEII tuners and receivers will give excellent results when.used with the MPX-100. Your MPX-100 has also been designed to oper- A' ate with any tuner or receiver employing either a ratio detector or a dis- criminator to demodulate the FM signal. Naturally, a multiplex adaptor designed to operate perfectly with such a widc variety of tuners must be provided with special controls. As a result of careful design and the use of precision parts, however, it was possible to reduce the number of controls on the MPX-100 to only three: the Separation control on the rear panel, and the Output Level controls also on the rear. The Separa- tion control must be adjusted to provide the maximum degree of stereo separation between channels for each particular model tuner. In addition, two MPX input jacks are provided on the rear panel, one to match tuners with low level outputs and the other to match those with high outputs. These adjustments need be made only once, when installing the MPX-100. (:otts~~lt the Installation Guide on page 3 for the correct MPX input jack and Separation control setting for your tuner. If your model tuner is not listed, determine whether it employs a balanced ratio detector. unbalanced ratio detector, or discriminator.

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GENERAL INSTALLATION tuner has m available aexiliarp pbww auhI an mitemate arraqm AND OPERATION INSTRUCTIONS -a would be ta wna~ the YPX-Im to it, and con- the t- te h smplih.) HE MPX-100 operates on AC only at 105-120 volts. One three- foot cable and two iour-foot cables are included to make con- nections to associated equipment. Any additional connections should be made with the same type of cable. Be sure to use the three-foot cable for the connection from the MPX output jack on your tuner since longer cable lengths will cause some loss of the higher fre- quencies. Both. MPX-100 outputs are low-impedance anode followers, permitting cable lengths up to 10 feet between the MPX-100 and your amplifier. We recommend that you keep the MPX-I00 right beside your tuner (but away from power transformers) for ease of operation and best performance. NOTE: Left (or L) designation corresponds to Channel A; Right (or R) corresponds to Channel B. ja&, If your tuner dw #=tor my be obtained f Installation of the "Yn eonneetor is WITH FM-AM STEREO TUNERS: . and tb glbr two plw 1-Connect the FM output of the tuner to the L INPUT jack on tho: MPX-100. (See Figure 1.) W'TH WM MQMOPHBNJC TUNERS? 1-'I% taner h4PX autput jack should be connw%ad to either the 3-The tuner MPX output jack should be connected to either the LOW LEVEL or HIGH LEVEL ja& on the rear panel ef the LOW LEVEL or HIGH LEVEL jack on the rear panel of the &PX-I&. Refer to the tsbb 0x1 page 3 (or wnmlt the mmufaaurer MPX-100. Refer to the table on page 3 (or consult the manufacturer of your tuner) te determine the jack whid Prlrzluld be 4 for this of your tuner) to determine the jack which should be used for this conatetion. Be sure bo as the tlirmf~fg~ cabLe supplied with the ronnection. Be sure to use the three-foot cable supplied with the %Connect the Erlaia tuner eaiprtt to the L INPUT jaek en the &Connect the L (left) and R (right) outputs on the MPX-100 to IWX-ZOO. If art additional outpet jack (with the sams led outpa) the corresponding Tuner input jacks on your stereo amplifier. &Connect the power cable of the tuner to the auxiliary power outlet on the rear panel of the MPX-100, and connect the power cable of ba~ween monopbaic and sterm the MPX-100 to an auxiliary outlet on your stereo amplifier. (If your 3-Follow step 6 and 5 far FM-AM stmw tunem

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Operation THE FISHER 0 POWER eo, STEREO BEACON UNIVERSAL MULTIPLEX ADAPTOR MODEL MPX-100 STEREO-MONO I AUTOMATIC TUNER STEREO OFo *co FF.O UAL NOISE FILTER SELECTOR Figure 2. Front panel of the MPX-100 INDICATOR LIGHTS: The red Power jewel on the front panel glows when power to the MPX-100 is turned on. The green Stereo Beacon automatically signals whenever the station tuned to is broadcasting an FM stereo program. It will remain off during monophonic programs. SELECTOR SWITCH: The Selector switch has four positions: AC Off: Power to the MPX-100 is turned off, but feedthrough connec- tions are provided from the tuner to the amplifier for monophonic FM, .. AM or stereo FM-AM programs. You will find this position particularly useful when listening to such programs for prolonged periods of time. When switching from AC OFF to another position of the Selector switch, it should be kept in mind that there will be a delay of approxi- mately 30 seconds, due to necessary tube warmup, before the MPX-100 will begin to operate. Tuner: In addition to providing the same feedthrough connections from the tuner to the amplifier, this position places the Stereo Beacon in operation. In the same manner as the AC OFF position, the tuner signal passes directly through the MPX-100, completely unaffected by the adaptor's internal circuitry. FM-AM stereo and FM or AM mono- phonic programs may be heard directly from the tuner with the Selector in this position. Whenever a multiplex FM stereo program is broadcast, the Stereo Beacon will automatically light. However, FM multiplex programs cannot be received stereophonically in the TUNER position, nor will the Automatic Switching teature operate. Stereo-Mono Automatic: This position is used for normal reception of FM multiplex broadcasts in stereo sound, and, due to the FISHER Automatic Switching System, may also be used for reception of I monophollic FM broadcasts. The Stereo Beacon will light whenever 4, a multiplex program comes on the air, and the MPX-100 will automati- cally switch into the stereo mode. When the station reverts to mono- phonic operation, the MPX-10 will automatically switch to the mono- phonic mode and the monophonic signal will appear at both outputs of the adaptor. At the same time, the Stereo Beacon will be turned off. This feature makes manual switching completely unnecessary 4 1 .1 4. ? d