User manual DRAKE DIGITAL VMM860AS

[. . . ] DRAKE COMPANY determines is due to: (1) Improper maintenance or repair, including the installation of parts or accessories that do not conform to the quality and specifications of the original parts. (2) Misuse, abuse, neglect or improper installation. All implied warranties, if any, including warranties of merchantability and fitness for a particular purpose, terminate three (3) years from the date of the original purchase. DRAKE COMPANY'S entire obligation with respect to this product, and the original purchaser shall have no other remedy and no claim for incidental or consequential damages, losses or expenses. [. . . ] Frequency Stability: Within ±5 kHz Output Flatness: From 54 to 864 MHz, less than 3 dB change. Output Amplitude Stability: ±1 dB Intercarrier Frequency: 4. 5 MHz Spurious Outputs (5 to 900 MHz): -60 dBc, (-15 dB A/V ratio and output level of +45 dBmV). In-Channel C/N: 65 dB typical, 4 MHz bandwidth. Broadband Noise: -78 dBc typicial, 4 MHz bandwidth @ +45 dBmV output. VIDEO Input Level for 87. 5% Modulation: Video Over-modulation LED: Input Impedance: Frequency Response: C/L Delay: Differential Gain: Differential Phase: Figure 1 F1 - POWER/ERROR Indicator Lights when the unit is connected to the required source of DC power via the rear panel DC INPUT connector. A flashing condition indicates an invalid channel setting or other conditions that would cause the unit to operate on an invalid channel. The RF output is switched off for flashing (ERROR) conditions. F2 - AUDIO Level Control The setting of this screwdriver adjustment determines the aural carrier deviation. Clockwise rotation increases the carrier deviation. F3 - VIDEO Level Control The setting of this screwdriver adjustment determines the video modulation level. CW rotation increases the modulation depth. F4 - Channel Number Switch Sets the desired operating channel for standard CATV channels 02 through 135 or Broadcast TV channels 02 through 69. See also Item F5 which sets the type of channel (CATV or Broadcast TV) and sets the leading "1" for CATV channels 100 through 135. Setting for CATV channel "125"Setting for CATV channel "25"0. 65 Vp-p to 1. 5 Vp-p. (VMM860AS only) 75 Ohms, return loss of 26 dB minimum. 30 maximum (10 to 90% APL). 2 CATV CATV +100 5 BC TV CATV +100 2 CATV 5 BC TV F6 - A/V Ratio Control This screwdriver adjustment varies the level of the aural carrier over a range from 12 to 22 dB below the visual carrier. Typically, the aural carrier should be adjusted to approximately 15 dB below the visual carrier. Clockwise rotation increases the aural carrier level. F7 - RF Output Level This screwdriver adjustment permits adjustment of the RF output level over a minimum of 10 dB range. LK (Pilot Lock) This LED indicates that the BTSC circuitry in the VMM860AS has locked to the video sync reference. F9 - Audio Overmodulation This LED illuminates when the audio input level reaches full modulation. (VMM860AS) F10 - Video Overmodulation This LED illuminates at 87. 5% video modulation. [. . . ] For normal mono audio, set switch to NORM position. If the MMTS20 BTSC stereo encoder is used, set this switch to FLAT and connect stereo audio to the MMTS20. This is the an unbalanced input for the right channel stereo audio. INTERNAL JUMPER SETTING: STD, HRC, IRC STD HRC IRC Drawing is not to scale. The power supply in the four position rack system can power up to four VMM860AG or VMM860AS modulators or any mix of fixed and agile VMM models up to four total modulators. [. . . ]