Test

When the wiring has been completed and has been checked for accuracy against the Pictorial Diagram, the tubes may be inserted, the pickup connected and the unit made ready for test. On the first test it 1b best to place the oscillator near the receiver or at least near the antenna leadln (which must not be shielded If wireless operation Is to be obtained.)

The Ctia88is of the Wireless Phonograph Oscillator must not be grounded since the signal radiates from the chassis.

The switch on the end of the chassis should be turned clock-wise to heat up the unit. (When the unit is operating the line cord will become quite warm. This is normal to the operation of thiB and certain other types of AC-DC apparatus.)

When the tubes have warmed up, usually about one minute, start a record playing and, if there is a volume control on the pickup, turn the volume control to maximum. Turn the volume control on your radio set to approximately the position used for local broadcasting stations and tune the receiver (on the broadcast range) as if looking for a local station. The phonograph record will be heard some place on the dial.

In the top of the coil can on the oscillator there is a hole through which an adjusting screw is visible. A shaft with a tuning knob also projects from this end of the coil can. Both of these adjustments are tuning adjustments on the oscillator. The former Is the rough adjustment while the knob and shaft actuate the fine adjustment.

If the phonograph signal is being interfered with by any strong signal it is a simple matter to shift the frequency of the oscillator by turning either or both adjustments, re-tuning the Bet to the new oscillator frequency until a frequency free from interference is found.

If the radio hums when the phonograph pickup arm is touched, the connections from the pickup to the Phonograph Oscillator should be reversed. (On some pickups this phenomena will not be present.)

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