Olson Technology OTM-3000-CV - Manual (Page 5)

025-000041 REV C Page 5
6) AUDIO MODULATION ADJUSTMENT
A) Connect an audio source of 300mV p-p (minimum) to the balanced audio input connector (600 ohms
input Z) on the rear panel. The source should be typical of the program material to be carried.
B) Rotate the audio modulation level adjust control slowly clockwise until the audio overmodulation LED
just begins to blink. CAUTION: Overmodulation can result in severe distortion in some TV sets. Set
this control at peak program levels.
7) RF AND AURAL CARRIER LEVEL ADJUSTMENT
A) Using a field strength meter, set the video carrier to the desired level with the RF output level adjust
control.
B) Tune the field strength meter to the aural carrier (4.5MHz above the video carrier).
C) Adjust the aural carrier level control to the desired level, typically 15dB below the video carrier.
CAUTION: Reducing the visual/aural carrier ratio to less than 15dB can result in high out-of-band
spurious signals in adjacent channels.
8) MISCELLANEOUS
A) The OTM-3000 CV is BTSC stereo compatible. It is shipped in the “mono” mode. To defeat pre-
emphasis, in order to use a composite BTSC baseband input signal, move the internal jumper plug
from W2 “PRE” to W2 “BY”. This plug is located in the left front area of the circuit board.
B) This unit is equipped with video and audio I.F. loops. Both loops are connected with two type F short
jumpers. If these become disconnected or misplaced, then the OTM-3000 CV will not perform
properly.
C) If a scrambling unit is utilized with the OTM-3000, follow the instructions associated with the scram-
bler. The video I.F. output level is +40dBmV, and the audio carrier level is determined by the aural
carrier level adjustment - typically +17dBmV @ 15dB A/V ratio.
D) This unit is equipped with a 0.5A slo-blo fuse. For continued safety and to maintain proper perfor-
mance of the unit, please replace only with an equivalent fuse.
E) A -20dB test point (type F connector) is provided in the rear panel.