HT 30/35CD transmitters

Transcription

1 HT 30/35CD Transmitter HARRIS, the world leader in broadcast technology, proudly presents HT CD Series FM transmitters. Featuring a rugged, world-proven design, HT CD transmitters are the world s first tube transmitters to incorporate a digital FM exciter as standard with other advanced features. The result is a series of transmitters that will far exceed your current expectations without compromising your ability to meet future requirements. HT CD transmitters use a single conservatively-rated tetrode in a high-efficiency quarter-wave cavity to produce rated power. With twice the bandwidth of folded half-wave cavities, Harris quarterwave cavity has demonstrated its superior performance in many hundreds of installations worldwide. HT 30/35CD transmitters provide typical PA efficiency of 80 percent for cost-effective operation. Harris DIGIT CD Digital FM Exciter is at the heart of HT CD transmitters. Introduced in 1993, DIGIT CD is not only the first exciter to digitally generate an FM signal, but it is the first exciter that can directly accept a digital studio-standard AES3 audio signal. DIGIT CD is available with an analog input module or a digital input module: If you do not yet have a digital signal path to the transmitter, you can use DIGIT CD with the analog input for performance that surpasses the best of today s analog exciters. When you do have a digital program path to the transmitter, you can replace the analog input module with the digital input module in minutes. DIGIT CD s digital input module will give you two distinct advantages, a DSP-based stereo generator and a Digital Composite Limiter (DCL). The digital stereo generator provides unsurpassed stereo performance with stereo separation over 60dB and inaudible noise and distortion. The DCL uses proprietary look-ahead circuitry to anticipate and eliminate overmodulation peaks before they occur. The result is the loudest, cleanest signal on the dial. Among other advantages, DIGIT CD allows channels to be selected in 50Hz increments with no requirements for output tuning, is ideal for N+1 operation. Beyond unrivaled performance, HT CD transmitters provide exceptional on-air availability. Among standard features that enhance reliability and prolong component life are incremental (or ramp-up) soft-start to protect the tube when the transmitter is turned ON; loss of phase protection; automatic power control which maintains constant power despite AC line-voltage fluctuations, and automatic AC restart which returns the transmitter to the air after a power failure. Automatic VSWR foldback ensures continued operation at the highest safe power level during antenna icing conditions, and Harris FlexPatch, an internal RF patch panel, makes it easy to bypass the preamplifier, the IPA or the PA for continued operation at reduced power should an emergency occur. HT 30/35CD transmitters are engineered for straightforward operation from day one. A front-panel signal flow block diagram uses tri-color LEDs to show circuit status for instant problem recognition. A digital multimeter provides multi-digit accuracy, including proper units of measure for 48 different parameters. A non-volatile memory stores time/date of up to 56 overload events for quicker troubleshooting. IPA forward and reflected power are shown simultaneously on a dual bar-graph display for easy tuning and matching. An optically-isolated remote control command and status interface provides a ready link to standard remote control systems. HT 30/35CD transmitters are available in combined configurations for high power applications. We invite you to take a closer look at HT 30/35CD FM transmitters to see why this family provides the best performance, reliability, and value in its class.

2 HT CD SERIES DIGIT CD Digital FM Exciter Analog or Digital Field Changeable Digital Analog HT 30/35CD DIGIT is supplied with a digital AES3 or an analog input module. Modules can be changed easily in minutes. MODEL POWER RANGE POWER CONSUMPTION HT 30CD 10,000 TO 30,000W 44.8kW TYPICAL AT 30kW HT 35CD 10,000 TO 35,000W 52kW TYPICAL AT 35kW Power Amplifier HT 30/35CD transmitters use a single 4CX20,000D tetrode in a broadband quarter-wave cavity to provide superior signal performance. The power amplifier is fine-tuned without sliding, high-current RF contacts. The conservatively-rated operation of the tube also provides exceptionally long tube life. Typical PA efficiency is 80 percent. Broadband Solid-State Driver The modular, 150-watt preamplifier and 700-watt MOSFET IPA develop about 600 watts of drive for the power amplifier. Using an advanced design, the driver provides superior performance year after year with virtually no maintenance. Digit CD Digtal FM Exciter The standard exciter in all HT CD transmitters, DIGIT CD is the world s first FM exciter that can directly accept studiostandard AES3 digital audio and will allow you to deliver 16-bit digital audio with true compact disc quality to your listeners.

3 HT 30/35CD Block Diagram DIGIT CD is available with either an analog input module or a digital input module. If you do not yet have a digital signal to your transmitter, the analog input module will give you a level of performance that exceeds the best analog exciters. And, when you are ready, you can change to a digital input module in minutes. Cooling System A high-efficiency, low-velocity direct drive air system provides ample cooling for the PA tube and driver while maintaining extremely low ambient noise levels. Flexpatch RF Patching This internal RF patch panel makes it easy to bypass the preamplifier, IPA or even the PA for continued operation in an emergency. Power Supplies The HT 30/35CD includes a very conservatively-rated high voltage power supply in a separate cabinet for flexibility of installation. Transmitter Control A microprocessor-based controller with discrete logic back-up is located on the front panel. Adjustable/metered filament voltage control is also provided. Automatic power control maintains constant incoming voltage to the transmitter despite line-voltage fluctuations. Proportional VSWR foldback ensures operation at the highest safe power level under antenna icing conditions, and automatic AC restart returns the transmitter to the air after AC power failure. A standard ramp-up soft-start feature provides protection to the tetrode when the transmitter is turned ON. Remote Control Interface Each HT CD transmitter features an optically-isolated remote control command and status interface which is compatible with major remote control systems. Status Information A front-panel signal flow block diagram uses tri-color LEDs to show circuit status for instant problem recognition. A digital multimeter provides multidigit accuracy, including proper units of measure, for 48 different parameters. A non-volatile memory stores time/date of up to 56 overload events for quicker troubleshooting. IPA forward and reflected power are shown simultaneously on a dual bargraph display for easy tuning and matching.

4 Make These HT 30/35CD benefits yours: Advanced tetrode technology and Harris DIGIT CD Digital FM Exciter enable HT CD transmitters to deliver the true 16-bit CD-quality sound preferred by today s listeners. DIGIT CD s field-changeable analog and digital input modules let broadcasters upgrade to an all-digital air-chain in minutes. Single, rugged long-life tetrode in Harris broadband quarter-wave cavity proven to offer superior performance in installations on six continents. Typical PA efficiency of 80 percent reduces operating costs. Standard automatic power control, ramp-up soft-start, proportional VSWR foldback and other features provide top on-air reliability. Harris FlexPatch RF patching keeps HT CD transmitters on the air in emergencies. Straightforward controls and front-panel displays simplify operation for any user. Accessible interface provides direct link to standard remote control systems. Highly efficient air system maintains extremely low ambient noise levels. Backed by broadcasting s most extensive factory support, including 24-hour technical assistance, around-the-clock parts, and comprehensive training. Manufactured under ISO 9001 Quality Standard. HARRIS WORLD FIRSTS IN DIGITAL BROADCAST TRANSMITTERS 1987 Harris introduces Digital Amplitude Modulation technology used in DX Series medium wave broadcast transmitters Harris demonstrates prototype digital FM exciter Harris introduces DIGIT, world s first digital FM exciter Harris introduces AES3 input module, which allows DIGIT to directly accept digital studio-standard audio Harris introduces second-generation DIGIT CD Digital FM Exciter Harris introduces world s first uncompressed digital 950 MHz STL, CD Link Harris Platinum Z becomes the first solid-state FM transmitter to amplify a digital IBOC signal.

5 Harris Broadcast Communications Division Headquarters Harris Broadcast Communications Serving Broadcasters In More Than 150 Countries With Next Level Solutions Since 1922, Harris has set the pace worldwide for the broadcast industry. Our more than 60 major "firsts" in RF technology have changed the way the world sees and hears itself and our innovations have extended to support for our customers as well. We pioneered around-the-clock technical service and parts, and we are the only transmitter manufacturer to sponsor a full-time Broadcast Technology Training Center. Beyond the radio and television transmission products we manufacture, we are the world's leading supplier of studio equipment and a leader in the design and integration of custom systems. You can count on Harris for any level of support you desire, from a single piece of equipment to a fully integrated broadcast system. We welcome the opportunity to be of service. Broadcast Communications Division 4393 Digital Way Mason, OH USA phone: broadcast@harris.com Copyright 2000 Harris Corporation ADV. 951A 12/00

6 Radio Systems Products HT CD Series 30 kw and 35 kw FM Transmitters with Harris DIGIT CD Digital FM Exciter