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INSTRUCTIONS FOR DRAKE MODEL 2-CQ SPEAKER/Q-MULTIPLIER

Installation with Model 2-C Receiver

bulletPlug Q-Multiplier cable into 2-CQ socket on rear of 2-C.
bulletConnect t speaker lead to jack on 2-C marked SPKR. ’
bulletWhen the Q-Multiplier is not being used, the PEAK-NOTCH switch should be on NOTCH and the ON-OFF switch should be on OFF.

Operating Instructions 

Finding the notch setting of the 2-CQ controls for the first time may present a problem, However, practicing with a strong steady carrier such as our 2-AC Crystal Calibrator should enable the operator to obtain good results if the following procedure is carried out.

bulletWith the 2-CQ switches in the ‘OFF and NOTCH positions, tune in a crystal calibrator signal on the 2-C Receiver.
bulletSet the Q-BALANCE control to about 12 o’clock and turn ON-OFF switch to ON.
bulletCarefully tune the TUNING knob for a slight null in S-meter reading. It will probably be shallow and rather broad. .’
bulletWhen the null is found, readjust the Q-BALANCE for further null. Alternately adjusting Q-BALANCE and TUNING controls should produce about 50 dB of attenuation. Leave Q-BALANCE control at this setting for all notching.

Notching out a Heterodyne on SSB or AM . P-m- ,

bulletWith the Q-BALANCE control set as described above, turn ON-OFF switch to OFF OFF. i
bulletTune in the station you wish to hear in the normal manner a s described in the 2 -C manual.
bulletWhen a heterodyne appears, turn the ON-OFF switch to ON and slowly turn TUNING knob to a ‘position where the heterodyne is eliminated. : NOTE: On AM .a heterodyne is caused by a beat between desired carrier and an interfering carrier. Removal of either will stop the heterodyne but if you notch out the carrier of the desired signal, the audio will become greatly distorted.
bulletIf the interfering carrier drifts in frequency, follow it with the Q-Multiplier TUNING  i.e., you tune the receiver for the best signal and tune the Q-Multiplier to remove the interference.

Keep in mind that the Q-BALANCE control is a balancing device when the 2-CQ is used for notching and as such it has only one correct setting. Even a few slight movement of this control from its correct setting will result in a drastic reduction attenuation. 

Peaking a CW Signal .

bulletWith the 2-C Q switches set for OFF and NOTCH, tune in a CW signal on the 2-C Receiver as described in the instruction book.
bulletNow set the 2-CQ switches to ON and PEAK and tune the TUNING control to -- the signal by noting a marked increase in the S-meter reading.
bulletSet the (Q-BALANCE control for the desired sharpness of response. Adjusting the Q-BALANCE control clockwise to .a point just short of where the unit breaks into oscillation will result in maximum selectivity for peaking purposes.

ALIGNMENT

To remove the 2-CQ from the cabinet, remove the 3 bottom screws. Pull the bottom of the unit to the rear until it is in horizontal pane. Rotate the unit about 45° and pull straight back out of the case.

bulletPlug the 2-CQ into the receiver.
bulletTurn the receiver on and tune in a strong steady carrier or a signal such as the crystal calibrator, zero beating it against the BFO
bullet Make sure the 2-CQ is switched to OFF and NOTCH and adjust L2 of the 2-CQ to peak s-meter reading.
bulletSwitch the 2-CQ to ON and PEAK turn the TUNING control until it points to the center of Its scale, and tune the Q-BALANCE control anywhere below the point of oscillation.
bulletThen adjust L1 (the coil in the aluminum can) far peak S-meter reading.

This completes the alignment procedure Return the 2-CQ to its case by reversing the removal procedure.

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No copy of text or image without a written authorization : email: JM CHERRY
Last updated on: 24 Dec 2011