User manual DRAKE DIGITAL DAR8618 QUICK GUIDE

[. . . ] The Gain and Slope controls both have a range of 10 dB minimum and operate between the preamp hybrid and the output hybrid to maintain a low noise figure over a wide range of gain and slope settings. Only the DAR8618 has a power doubled output hybrid with no input preamp and no adjustable gain and slope controls. All models have a provision for optional fixed input attenuators and equalizers. Double-sided, plated through hole, glass epoxy, printed circuit boards, and SMT are used for low losses and maximum reliability. [. . . ] Be sure to leave at least one open rack space above and below the amp to allow proper ventillation. 6) While monitoring the output levels at the Output Monitor -30 dB test port, adjust the Gain control for desired output at the high end of the band. Then monitor the lowest channel and adjust slope control to equalize this channel to the desired level (usually equal to but not higher than the high end of the band). Since there can be a slight interaction between the slope and gain settings, it is advised to repeat this step a few times to ensure the desired levels are attained. NOTE: The -30 dB input and output test ports can be used to monitor input and output levels. These are only accurate when the load is connected to the amplifier output and power is on. A WORD CONCERNING INPUT LEVELS It is important to keep the input level to the amplifier within an optimum range. If the level is too high, higher nonlinear distortion will result and if the level becomes too low, C/N might be less than desired. As a general rule, stay within the optimum input level range listed in the specifications. In general, install a fixed input attenuator if required to set the highest frequency channels in the input to within the optimum range. Then set the amplifier gain to achieve the desired output level, not to exceed the maximum output level listed in the specifications. Then, if the low frequency channels are above the optimum input level range, a fixed input equalizer can be installed to drop the low frequency channels to within this range. Use the slope control to make fine adjustments. INSTALLING FORWARD PATH INPUT ATTENUATOR Remove top cover as described below. If input levels are enough to cause a high distortion level in the input amplifier, a fixed input attenuator may be added. Choose an SXP type attenuator of the value required, and install at the location indicated below. INSTALLING AN INPUT EQUALIZER Follow the same basic procedure as described above for the input attenuator except that the equalizer is installed at the equalizer location shown below: RF INPUT OF REAR PANEL IN OUT GROUND IN GROUND OUT FIXED INPUT ATTENUATOR LOCATION A factory installed jumper is installed here for no attenuation. To install an input attenuator, remove jumper and plug in a "SXP" type attenuator rated for the same or higher frequency as the amplifier. INPUT EQUALIZER LOCATION A factory installed jumper is installed here for no equalization. If equalizer is not used, the jumper must be connected between the IN and OUT connections. 4 Specifications and Warranty SPECIFICATIONS COMMON TO ALL MODELS (unless otherwise noted) Forward Gain Adjustment Range: Slope Control Adjustment (54 MHz): Input/Output Impedances: Input and Output Monitor Ports: Fixed Input Attenuator: Fixed Input Equalizer: Hum Modulation: Frequency Coverage (return port): RF Shielding: 10 dB minimum (except DAR8618). [. . . ] - 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. Some states do not allow limitations on how long an implied warranty lasts or do not allow the exclusions or limitation of incidental or consequential damages, so the above limitation and exclusion may not apply to you. - This warranty gives you specific legal rights and you may also have other rights which vary from state to state. [. . . ]