Heathkit Model AD-1309

Pink/White Noise Generator

Calibration Procedure

· Set the POWER OUTPUT switch (on front of unit) full counter-clockwise to the OFF position.

· Disconnect all external components from the front panel terminals.

· Install a fresh 9-volt battery

· Calibration is required only when used with a real-time spectrum analyzer.

Ancillary Equipment Needed

Spectrum Analyzer

Shielded cable

* * * * * * *

HIGH FREQUENCY ADJUSTMENT

Refer to PICTORIAL 4-1

Construction manual page 20

(    )         Set the spectrum analyzer power switch to the ON position and allow the unit time to stabilize.

(    )         Set the spectrum analyzer input attenuator to the 1 dB/div scale.

(    )         Connect a shielded cable to the external input jack of the spectrum analyzer.

(    )         Connect the shielded cable to the generator’s pink noise output jack J2.

(    )         Set the generator’s POWER OUTPUT control to the ON position.

(    )         Adjust the POWER OUTPUT control clockwise until a meaningful display is shown on the spectrum analyzer.

(    )         Adjust the spectrum analyzer external input attenuator control as necessary.

· If the spectrum analyzer display shows a flat response from 1 kHz to 20 kHz – no calibration is needed.

· If a .0022 uF capacitor is installed into the two sockets at C3 on the circuit board, adjust trimmer R1 as necessary to obtain the flattest frequency response.

· If there is unacceptable high-frequency roll off with no capacitor at C3 – continue as follows:

(    )         Insert a .0022 uF Mylar capacitor into the two sockets labeled C3 next to the 10 uF electrolytic capacitor C4 on the circuit board.

(    )         Adjust the trimmer R1 on the circuit board through its range until the flattest frequency response is displayed on the spectrum analyzer.

· If the frequency response obtained using C3 is NOT an improvement or too much high-frequency boost is generated – remove capacitor C3. Calibration is now completed. Go to the last five steps marked * below.

· If the frequency response obtained using C3 is an improvement – solder capacitor C3 into the two sockets.

(    )         Adjust the trimmer R1 on the circuit board through its range until the flattest frequency response is displayed on the spectrum analyzer.

(    )*       Set the generator’s POWER OUTPUT control to the OFF position.

(    )*       Disconnect the shielded cable from the generator’s pink noise output jack J2.

(    )*       Disconnect the shielded cable from the external input jack of the spectrum analyzer.

(    )*       Set the spectrum analyzer power switch to the OFF position.

(    )*       Calibration procedure is complete.