Repository navigation
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 (or newer) you may want to buy a USB 3.1 or 3.2 Gen 2 card, or a ExpressCard to USB 3.0 adaptor.
Connect power & data interface
To confirm data is being set over YUV, open your MS21xx device inside OBS or FFplay etc, or run misrc_capture directly.
Connect an input signal, adjust your gain and DC offset pot(s) until the terminal is no longer reading out a clipping samples warning.
Do a test capture to ensure your basic config is working, then fine tune up or down your gain, however it's best to start with -1 dB or 0 dB gain, with 12-bits resolution you have a very high latitude for amplification range
Important
To capture CVBS or Composite Baseband RF Ensure SW101 DIP's 1 & 4 are set to 0 these enable AC coupling, your DC offset will have to be tightly calibrated also.
There are 10 dips or 2 pairs of 5 for each ADC channel & amplifier path.
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.
| 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 |
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 | 01 | 0 | 1 | ||
| 75 Ohm | 00 | 0 | 0 | ||
| 37.5 Ohm | 10 | 0 | 1 | ||
| 30 Ohm | 11 | 1 | 0 |
75Ohm Is standard for Video applications. (also stock for ADA4857 Amplifyers)
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 | 1 | ||
| Zero Adjust Trim Pot | XX1 | 0 |
When value 3 of the 3 Pin DIP is in the 0 position the value can be adjusted with the trim pot marked zero adjust next to the input BNC.
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 |
DIP 3 & 4 (3 Pin)
There are 2 input stages and 2 operational amplifiers.
This is controlled by the DIP switches.
There is 2 Gain DIPs for Negative/Positive bias, you want to mirror the values on both + / - dips 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 |
