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User Guide

Harry Munday edited this page Nov 5, 2024 · 4 revisions

User Guide

USB 3.0 - Ensure no other high bandwidth items such as card readers, capture cards, cameras etc are connected to the bus.

If your system does not have USB 3.0 you may want to pickup an USB 3.1 or 3.2 Gen 2 card, or a ExpressCard to USB 3.0 adapter.

Hardware Dips

There is 10 dips or 2 pairs of 5 for each ADC channel & amplifier.

1 = Up

0 = Down

This value is relative to the orientation of the label on each physical DIP switch i.e ON will always be at the top position of a DIP.

Important

To capture CVBS RF Ensure SW101 DIP's 1 & 4 are set to ON - this enables AC coupling.

Layout

Colour Key DIP Switch Value Description
Black Amplifier
White ADC Analogue to Digital Converter
RED DIP 1 AC/DC Coupling Pre-Termination
Green DIP 2 Bias Adjust DC Bias manual trim pot adjustment
Blue DIP 1 & 2 Input Impedance 50 Ohm or 75 Ohm etc
Violate DIP 1 AC/DC Coupling Post-Termination
Yellow DIP 3 / 4 Gain Control Negative & Positive Gain Control
Pink DIP 5 Range 1vpp or 2vpp input voltage range
Orange DIP 5 Format Signed/Unsigned sampling mode

Coupling & Input Resistance

This uses 2 DIPS all of one and 2 of the other

DIP 1 (4 Pin)

Value 1 Sets Pre-Termination

Input Termination Setting 1 2 3 4
AC Coupling 0XXX 0
DC Coupling 1XXX 1

0 AC Coupling

1 DC Coupling


Value 2 & 3 (Mirrored 2 & 1) Sets Input Impedance

Input Impedance Ohm Setting 1 2 3 4
50 Ohm 10 1 0
75 Ohm 00 0 0
37.5 Ohm 10 0 1
30 Ohm 11 1 1

75Ohm Is standard for Video applications.

50Ohm Is standard for RF applications


Value 4 Sets Post-Termination

Input Termination Setting 1 2 3 4
AC Coupling XXX0 0
DC Coupling XXX1 1

0 AC Coupling

1 DC Coupling


DIP 2 (3 Pin)

Input Impedance Ohm Setting 1 2 3
50 Ohm 10 1 0 0
75 Ohm 00 0 0 0
37.5 Ohm 10 0 1 0
30 Ohm 11 1 1 1
Zero Adjust Static XX0 0
Zero Adjust Trim Pot XX1 1

When value 3 of the 3 Pin DIP is in the 1 position the value can be adjusted with the trim pot marked zero adjust.

Input Range & Format

DIP 5 (2 Pin)

Value 1 Sets Format

Value 2 Sets Range

This DIP assigns input range, and to used Signed or Unsigned sampling

Input Range Volts Setting 1 2
1Vpp 0 1
2Vpp 1 0
Unsigned 0 0
Signed 1 1

Gain

DIP 3 & 4 (3 Pin)

There is 2 input stages and 2 operational amplifiers.

This is controlled by the DIP switches.

There is 2 Gain DIPs for Negative/Positive, you want to mirror the values on both for standard use.

Silkscreen Label Based Positions

Gain dB Setting 2 1 0
20 0 0 0 0
13 1 0 0 1
9 2 0 1 0
6 3 0 1 1
3 4 1 0 0
1 5 1 0 1
0 6 1 1 0
-1 7 1 1 1

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