ChannelPlus DA-500A RF Distribution Amplifier — Manual

Installation and reference manual for the ChannelPlus DA-500A — a high-power, low-noise, low-distortion RF distribution amplifier for indoor CATV and off-air antenna distribution systems.

Overview

The DA-500A amplifies RF signals with a flat response from 50 MHz to 1000 MHz, suitable for all off-air and uni-directional CATV applications including VHF (high/low bands), FM, midband, superband, hyperband, ultraband, and UHF. It uses a low-distortion push-pull circuit design built with surface-mount and strip-line technologies for high reliability and a compact footprint.

Specifications

Physical Features

• Single F-type INPUT connector
• Single F-type OUTPUT connector
• Power jack rated +15VDC, 600mA
• Compact metal enclosure — indoor use only

Installation

Simple pass-through design: connect the antenna/cable source to INPUT, and run OUTPUT to the distribution system (splitters, TVs, etc.). Connect the included power supply to the unit's power jack.

Troubleshooting: Herringbone Patterns

Wavy "herringbone" patterns on the TV picture are caused by intermodulation (IM) distortion — spurious signals ("spurs") landing in the 6 MHz band reserved for a channel. The most common cause is an over-driven distribution amplifier.

Diagnostic test: Insert a variable attenuator before the amplifier. If increasing attenuation makes the herringbone pattern disappear, the amplifier is being over-driven.

Common causes of an over-driven amp:

1. Too much gain in the system — use the variable attenuator to find a setting where signals are clean and the amp isn't over-driven.
2. Strong local FM signal — may require an FM trap installed before the amplifier.
3. Strong local TV signal — may require a tuned filter to reduce that station's signal (station management can sometimes supply filters for their neighbors).

Variable attenuators and FM traps are available at most hardware and electronics stores. For more troubleshooting tips and installation advice, visit www.channelplus.com.

Warranty

Linear LLC warrants this product free from defects in material and workmanship for 2 years from the product's date code. Warranty is limited to repair or replacement (freight prepaid to Linear LLC); no provision for labor cost or other reimbursement. Excludes damage from abuse, negligence, electrical surge/lightning, water damage, natural disasters, tampering with date codes/labels, or shipping damage. Requires a Return Product Authorization Number (RPA#) — contact Linear Technical Services at 1-800-421-1587.

Contact

ChannelPlus / Linear LLC · (760) 438-7000 · Toll-Free (800) 996-5225 · Toll-Free Fax (800) 468-1340 · www.channelplus.com