Distribution Equipment For 400 MHz Co-Axial Communications Systems (1980)

By James R. Palmer, C-COR Electronics, Inc.

Comments on 400 MHz systems have been "on the record" in my monthly commentary newsletters. Generally, 400 MHz systems must be reduced in length from that of 300 MHz systems to produce the same quality. Perhaps as many as four times as many hubs will be required due to the reduced reach.

C-COR is very happy to design, manufacture and sell equipment for 400 MHz systems. It is going to cost more and you are going to need a lot more amplifiers. Where does C-COR stand?

  1. Mainline Passives 400 MHz splitters, directional couplers and other mainline passives devices will be in production in June. These units will take the place of the 350 MHz units now in production.
  2. Trunk Amplifiers Trunk amplifiers will be in production for shipment in September. These amplifiers will be available with TV carrier automatic level control as an option in addition to our standard modulated pilot automatic level control.
  3. Distribution and Line Extenders The single hybrid line extender for 400 MHz use is in production now, being built with 300 MHz hybrids. When a 400 MHz 33dB gain block is available from the hybrid manufacturers this unit can be immediately shipped.

We have developed a 2 hybrid line extender for 400 MHz. This unit is available to place in production if and when the necessary hybrids are available in quantity.

C-COR has near completion the development of a quad line extender. This unit will be available to start shipments in September on a first come, first serve basis.

Both hybrid manufacturers, Motorola and TRW have had difficulties in supplyinq 300 MHz hybrids to industry demands. Both have reneged on orders that had been accepted by them and have gone to allocation of their production. They are both sunplvinq sample quantities of 400 MHZ devices that are essentiaLLy 300 MHZ units tweaked to function at the 400 MHz.

I am skeptical concerning announced improvements in hybrids with lower noise figure and higher outputs. Both manufacturers have had difficulties doing development to an announced time schedule. If the historical delays in new development can be translated to the future, it is my opinion that it will be a long time before we see any improved performance.

C-COR is firmly committed to the 400 MHz product line. With three different approaches to the line extender, the item using the most solid state devices, I believe that we have a good hedge to give amplifiers to those that place early orders. Most equipment for 400 MHz requires 400 MHz hybrids and that supply is going to be slow and problematic. Our line extender with the quad does not have that problem.

By clicking the "Download Paper" button, you are agreeing to our terms and conditions.

Similar Papers

Distribution Equipment For 400 MHz Co-Axial Communications Systems
By James R. Palmer, C-COR Electronics, Inc.
A Model For Predicting Surge Characteristics Internal To Broadband Distribution Equipment
By Steven A. Grossman, C-COR Electronics, Inc.
Performance Of A 400 MHz, 54 Channel, Cable Television Distribution System
By Rezin E. Pidgeon, Jr., Scientific-Atlanta, Inc.
Specialized Test Equipment For CATV Distribution Measurements
By George P. Dixon & Thomas F. Kenly, C-COR Electronics, Inc.
An Off-Premises Converter With Multiple Signal Paths
By Charles M. Palmer, C-COR Electronics, Inc.
Rural Distribution Systems: A New Technique For Small System Trunking
By John A. Hastings, C-COR Electronics, Inc.
The Hidden Costs Of 400 MHz
By Archers. Taylor, P.E., Malarkey, Taylor & Associates, Inc.
Temperature, Temperature Design, and Automatic Level Control for CATV
By James R. Palmer
The Design, Construction, Cost And Performance The First 400 MHz Cable Television System
By Gerald Bahr, Jeff Blowers, Ed Dice, and Dan Doorn, Cox Cable Communications, Inc.
Preparations for Deploying & Lessons Learned from Deploying High Split (204 MHz) on I-CCAP, R-PHY, & R-MACPHY - High Split as a Steppingstone Towards DOCSIS® 4.0
By Craig Coogan, CommScope, Inc.; Jamie Brown, Shaw Communications, Inc.; Zoran Maricevic, Ph. D., CommScope, Inc.
More Results >>