Moto Meter Gauge & Equipment Co. Moto-Vox 10-A Schematic

Moto Meter Gauge & Equipment Co. Moto-Vox 10-A

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Product Information:
Model:Moto-Vox 10-A
Manufacturer:Moto Meter Gauge & Equipment Co.

Schematics Content

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Total drain with input of 5.7 volts. 28 mils at 200 volts.

Take readings at tube sockets, when receiver is tuned off signal.


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Chassis Wiring Above Serial 500

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SPECIAL INSTRUCTIONS MODEL " in AT ALL ELECTRIC ONLY POWER SUPPLY Provision has been made for mounting the power supply on the bottom of the receiver by means of two self-tapping 1/4 " sorews, which are assembled in the bottom.

The power supply may also be mounted beneath or behind either front or rear seat.

Mount the power supply. Run the separately shielded Red lead, assembled in the speaker, to the terminal *3.

Assemble the Red lead in the radio cable to the B - plus terminal in the supply and the Yellow lead to the B - minus terminal, making certain that the shield of the cable is anchored by the mounting clamp provided in the power supply. If the cable is too long, do not cut it off, but double it up neatly and place out of sight. Make certain that the shielding on the cable is grounded to the metal part of the car in several places.

Now connect the Black with Yellow tracer lead or the tuning control along with the Yellow lead from the power supply terminal # 2 to the Ungrounded post or the battery. Assemble the Black lead from terminal 1 of power supply to the grounded battery posto IMPORTANT:


The receiver is now ready to be connected up. Plug the cable assembly into the receiver. MAKE SURE THAT THE PLUG IS NOT FORCED ONTO THE RECEPTACLE ON THE RECEIVER BUT THAT IT IS ASSEMBLED PROPERLY. Then remove one of the screws in the end or the chassis and tasten the clip at the end of the shield to the chassis holding it in place by means of this soren.

Full the switob underneath the tuning control forward. Never turn this switch on unless the receiver is plugged into the harno88 assembly, thus making sure that the power supply is operating under load,


The installation is now complete with the exception of the elimination of certain noises known as interference, caused by the ignition systemie You will find in the MotoVoz package a complete set of suppressors for both coil and spark plugs for a six cylinder automobile. Assemble a spark plug resistor on each plug, (Diagrams # 1 and # 2) making sure that all connections are tight, as a loose connection at this particular point will render the resistor useless as well as interfere with the operation of the motor, Install the single coil suppressor provided in the top of the distributor.
In most cases the standard suppressors are very easily mounted. However, in the case or certain valve-in head motors, such as the Buick, it is necessary to use the Motovox screw-in type suppressor which can be screwed into the ignition cable and then snapped over the plug. Be certain at all times that in the case of a two coil system, that there is one coil suppressor in each high tension lead going to each coil at the distributor. the screw-in type suppressor can be purchased from Mete Meter at a nominal charge.
In addition to the suppressors, there are two by-pass condensers provided. One of these by-pass condensers should be placed on the live side or the generator, mounting the condenser bracket under the relay mounting screw and connecting the lead to the relay battery terminal. The other condenser should be mounted on the battery side of the soil. The can or condenser must be grounded.

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Since all of the adjustable condensers in this receiver have been accurately aligned in the process of manufacturing, it will only be necessary to adjust them when replacing one or more coils. This operation may be divided into two parts namely, First, Aligning intermediate frequency transformer trimmers and Second, Aligning gang condenser and series condenser trimmers.


Remove any external antenna from chassis and ground antenna on chassis during test. Connect one of the output leads of a 175 K.C. test oscillator to the control grid (top) cap of first detector tube (leaving grid cap terminal of lead in place on tube) and the other to the base of chassis, Connect an output meter in parallel with the primary of speaker output transformer at the terminal strip in the speaker housing. Turn the rotor plates entirely out of stater plates and adjust the adjustable trirmer in the top of coil "71" to the maximus meter reading. Then ad Just the trimmers in the top of composite "68" to maximum reading in the same manner. When this is accomplished the intermediate frequency of the receiver has been aligned to 175 K.C.

When replacing a gang condenser, series trimmers, composito, antonra, or R.F. coil it is necessary to realign the series trimmer and gang condenser trimmers. To do this fasten the tuning control to the chassis, turning the rotor blades all the way into the stater and setting the dial on 540 K.C. Now adjust a test oscillator to 600 K.C. and place one terminal on the base of the chassis and the thor on the antenna post of the receiver. (Remove the ground from this post). Connect the output meter as described above. Now rotate the tuning mechanism slowly back and forth at approximately 600 K.C. on the dial and adjust the series trimmer so that maximum reading is shown on the meter. During these measurements reduce the signal from the oscillator to approximately one half scale reading.

Now adjust the test oscillator to 1400 K.C., tune the receiver to 1400 K.C. on the dial and adjust the three trimmer condensers on the gang con denser to the maximum meter reading.

If the proper coil is used and the tuning condenser is calibrated properly, the maximum output will be obtained at each of the other frequencies. In some cases, however, after aligning at 1400, it may be necessary to bend the outside blades at the other frequencies to track properly. This should only be done by an experienced radio service man and the receiver should always be aligned last at 1400 K.C.

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Take readings at tube socket contacts when receiver is tuned off signal.

Total Drain 19 milliamperes.

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In the case of Nodel " in ET 1t is only necessary to assemble the Yellow lead in the "B" harness to the minus tap of 180 volts of battery. (Schematic Diagram # 2) Four Type 2308 Burgess Batteries are recommended for this purpose.
Then the Maroon load is assembled onto plus 45 and the Red lead is assembled to plus 180. A 1/4 amp. 250 mil. fuse is provided in the plus 180 line to avoid possible damage due to short circuits to different parts of the radio circuit.

In most cases it is possible to mount the batteries underneath the seat, or in rear of either front or back seat. In case this is not possible a battery box can be obtained at a very nominal cost from the factory It must be remembered that Model " in A and " in E'are not interchangeable as far as hook-up 1s concerned. Model in A is an All Electric Set and Model "10E" is Battery Operated and these circuits are wired accordingly. Therefore, it is not po 991ble to operate the Model * 10. A ". as a battery receiver and the Model * in F " as an all electric.

After the installation is completed, the receiver is now ready for sensitivity adjustment. Turn the receiver switch on and turn the dial off of a broadcast station between 1300 and 1500 kilocycles. The noise level at this point should be fairly high. Now turn the sensitivity control, AN EXCLUSIVE MOTOVOX FEATURE, located in the bottom of the receiver, entirely to the right or clockwise to the histop then turn back counter clockwise or to the lett, until the point is reached at which the statio level becomes very high. This is the point of maximum sensitivity. Any point beyond this in a counter-clockwise direction or to the left, will result in a lower sensitivity level and in a clockwise or right direction will result in a laok or sensitivity and automatic volume control. It is suggested that the control be set at a point just below the maximum sensitivity to reduce engine interference.
Therefore, be certain at all times that the sensitivity control is adjusted at the proper point.

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The model installation which is strongly recommended is to place the chassis on the right hand side of the dash as far up in the corner as it is possible and to place the tuning control unit on the left hand side of the instrument panel putting the speaker directly back of tuning control on the left hand side of dash.
Tho chassis may be mounted in any desired position, It is noc 888ary to drill four olearance boles for 1/4 " bolts and it is recommended that the four mounting bolts provided be secured to the case with the auts provided, and then the complete chassis can be held against the dash marking the location of the four bolos.

If it is desired, MotoVoz has an accessory mounting bracket # 76495, which can be obtained at all Motovor distributors at a very nomidal cont. This bracket permits the receiver to be mounted by drilling only one bole in the dash. In removing the receiver it is unnecessary to remove the bracket, but merely two mounting sorowo whion secure the receiver to the bracket. For further instruotions som directions accompanying the bracket.

The tuning control and speaker cable assembly are all completely attached and assembled together at the factory and it is only necessary to drill a clearance hole for a 3/81 bolt to mount the speaker on the dash. In case the bracket mounting which is provided for the speaker is not adaptable to the particular installation at band, it is necessary to remove the cover, unragten the mounting bolt and screw the mounting bolt in place in the tapped stud in the rear of the speaker. If this mounting is used be sure to spao. the speaker away from the dash at least 13 ". In using the conventional mounting the speaker should be placed in such a manner that the race or the speaker, that is, the side on which sorex heads show, should be mounted toward the center of the car, thus, giving a clear tone. The tuning control is fastened to the edge of instrument panel with two 1/4 " screws provided.

MOUNTING CHASSIS AND TUNING CONTROL In mounting the chas818 to the dash, make sure that the tuning control bracket on the case is mounted in such a manner that it tao towards the tuning control, then assemble the tuning control to the chassis propor.
Pull the short shaft and coupling extending through the side of the chassis entirely out and turn as far clockwise as possible. Then turn the tuning control knob in the same position and insert the driver on the end of the flexible shaft in the coupling. Then tighten the two screws in the coupling. Now insert the metal conduit on the outside of the flexible shaft in the tuning control bracket on the end of the case and tighten the two got screws in this bracket.

Run the drive shaft and the tuning control to the chassis in as direct a manner as possible, thus eliminating all kinka and bonds which would tend to make the drive biad. REMEMBER THAT THE SUCCESS OF THIS PARTICULAR TYPE OF CONTROL DEPENDS UPON SMOOTH OPERATION AND THIS CAN ONLY BE ACCOMPLISHED BY PROPERLY LINING UP THE PARTS. Care has been taken in the manufacture or these parts in the factory and only by properly resembled jobs in the field oan good results be obtained.

The final adjustment on the dial calibrations can be obtained after the power supply and the receiver are completely hooked up by tuning in on broadcasting stations. It is then a. comparatively simple operation to loosen the coupling on the flexible cable by means of the tvo set screws, rotate the dial to the proper position and routighton the so sorews.
Be sure that the screw which boids the tuning control, conduit in the tuning control housing does not bind too tightly as this may cause an excessive bind on the flexible cable. It is recommended that the Receiver be tuned on a Broadcasting station approximately 700 Kilocycles in making the above adjustment.

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