Low Noise Pre Amplifier - AS 1520

Features:

Low Noise Pre Amplifier
Control Room Application
Freq.: 40 ~ 860MHz
106 Ch. Loading Capacity
Accepts High I/P Level
18dB Gain
C/N better than 54dB
Good CSO, CTB characteristics
Dual Output
Mains –cum- Power pass
Voltage Selection LED
Plug-in Slope Card

Why Use Low Noise Pre Amplifier AS 1520:

Calculations for combiner losses with 30dB Hybrid Amplifier at headend:
Step 1: Average output level of modulator = 108dBµV
Step 2: Losses due to two combiners in series (Approx.) = 28dB
Step 3: Net output after combiners = 108 – 28 = 80dBµV
Step 4: Gain of Ordinary Hybrid Amplifier = 30dB
Step 5: Net O/P level after Hybrid Amplifier = 80 + 30 = 110 dBµV

This Output will result in Intermodulation & poor C/N. Even with the help of Gain Control of the amplifier, it may no be possible to avoid intermodulation.

To overcome this problem, Sharp Vision is manufacturing a Low Noise Pre Amplifier AS 1520. The gain is 18dB with high C/N & Low Noise Figure. Now the above calculations will stand as follows:
Step 3: Net output after combiners = 108 – 28 = 80dBµV
Step 4: Gain of AS 1520 = 18dB
Step 5: Net O/P after AS 1520 Amplifier = 80 + 18 = 98dBµV

This Output will have a high C/N, Low Noise & No Intermodulation – The result is a much better picture quality for the networks with high cascade.

Specifications:

Gain : 18dB
Adjustable Gain : 0~20dB Adjustable
Output Level : 100dBµV
Slope (Fixed) : 9/12/15dB (Optional) (Standard 0dB) (for 550/750/860MHz)
Flatness : + 0.2dB
Return Loss : > 14dB
Noise Figure : < 7dB
Monitor : -20dB
Mains Voltage : 220VAC + 10%, 50Hz
Power Pass : 30/40/50/60 VAC (Selection with Slide Switch)