Blonder tongue CMA-b User manual

Description
The CMA-b is a low noise, single channel VHF preamplifier with excellent gain and the ability to accept a wide
range of input signal levels, making it ideal for CATV and MATV headend installations. The CMA-b mounts on
the antenna mast and power is duplexed on the downlead, eliminating a separate power supply lead.
Features
• Very Low Noise Figure
• Excellent Gain, Flat Response
• Excellent Adjacent Channel Overload Rejection
• Output Monitor Jack Permits Testing Without Service Interruption
©2007 Blonder Tongue Laboratories, Inc. All rights reserved. Specifications are subject to change without notice. Trademarks are the property of their respective owner.
651094300M
INSTRUCTION MANUAL
One Jake Brown Road
Old Bridge, NJ 08857-1000 USA
[phone] • [phone] • FAX: [phone]
www.blondertongue.com
CMA-b
Low Noise, Single Channel Preamplifier
Stock No. 4706
Gain
CMA-b ch. 2 - 6: 29 dB, 26 dB min
CMA-b ch. 7 - 13: 26 dB, 25 dB min
CMA-b FM: 24 dB, 20 dB min
Bandpass Flatness
Channels 2 - 13: 6 MHz +/- 0.25 dB
FM: 1 dB, 2 dB max.
Noise Figure
CMA-b ch. 2 - 6: Less than 3.5 dB
CMA-b ch. 7 - 13: Less than 2.5 dB
CMA-b FM: 2 dB, 3 dB max.
Input Impedance: 75 ohms
Selectivity: 12 dB down 9 MHz
from center freq.,
10 dB min.
Minimum Recommended
Input for TASO Grade 1 (Excellent
Picture)
CMA-b 2 - 6 & 7 - 13: 300 µv (-10 dBmv)
Maximum Input for Just-Perceptible Cross
Modulation
CMA-b ch. 2 - 6: 36 dBmv
CMA-b ch. 7 - 13: 28 dBmv
Maximum Input for Just-Perceptible
Intermodulation
CMA-b ch. 2 - 6: 33 dBmv
CMA-b ch. 7 - 13: 26 dBmv
Operating Ambient
Temperature Range: -40˚ F to 140˚ F
Output Monitor Jack: -20 dB (Backmatched)
Power Requirement: -21 VDC at 40 ma
Connectors (75 ohms)
Input: Type F, Output, Type F, Output Monitor: Type F
Housing: Cast Aluminum
Dimensions: 5" x 3-7/8" x 2-5/16"
Shipping Weight: 1 lb., 5 oz.
Specifications (Typical)

One Jake Brown Road
Old Bridge, NJ 08857-1000 USA
[phone] • [phone] • FAX: [phone]
www.blondertongue.com
Installation
For best signal-to-noise ratio, the CMA-Uc should be mounted close to the antenna (See Figure 1).
Figure 1
CAUTION
RISK OF ELECTRIC SHOCK
DO NOT OPEN
Returning Product for Repair (or Credit)
A Return Material Authorization (RMA) Number is required on all products returned to Blonder
Tongue, regardless if the product is being returned for repair or credit. Before returning product, please
contact the Blonder Tongue Service Department at 1-800-523-6049, Ext. 4256 or visit our website: www.
blondertongue.com for further information.
WARNING: TO PREVENT SHOCK HAZARD, DO NOT EXPOSE THIS UNIT TO RAIN OR MOISTURE
NOTE TO CATV INSTALLERS
This reminder is provided to call the CATV System Installer’s attention to Article 820-40 of the NEC that pro-
vides guidelines for proper grounding and, in particular, specifies that the cable ground shall be connected to
the grounding system of the building, as close to the point of cable entry as practical.
TO REDUCE THE RISK OF ELECTRICAL SHOCK, DO NOT REMOVE COVER
FROM THIS UNIT. NO USER-SERVICEABLE PARTS INSIDE.
REFER SERVICING TO QUALIFIED SERVICE PERSONNEL
The lightning flash with arrow-
head symbol within an equilat-
eral triangle is intended to alert
you to the presence of unin-
sulated “dangerous voltage”
within the product’s enclosure
that may be of sufficient mag-
nitude to constitute a risk of
electrical shock to persons.
The exclamation point
within an equilateral triangle
is intended to alert you to
the presence of important
operating and maintenance
(servicing) instructions in the
literature accompanying the
product.
Under no circumstances should the unit be
mounted in an unventilated area or other location
where the ambient temperature may exceed the
rated maximum given in the specifications.
Figure 1 shows the method of attaching the CMA-b to the antenna mast
All hardware required to mount the CMA-b is supplied with the unit.
Note: -21 VDC must be supplied to the CMA-b from the output
cable. Blonder Tongue's model 1526 Power Supply is designed
specifically for this purpose.
The performance of the CMA-b can be checked at the -20 dB test
jack without interrupting service. A standard 75-ohm "F" connector
is used.
CMA-b - Instruction Manual