- SIGNA MR355 / SIGNA MR360
- Service Manual
- 5856356-3EN Revision 5.0
- Basic Service Documentation. Copyright General Electric Company.
- 00000018WIA306D9F20GYZ
- id_131064701.13
- Apr 23, 2020 7:18:25 PM
Receive Chain Theory
The following describes Receive Chain Theory.
Summary
Receive chain takes the low-level analog signal from the multi-coils to the Mega SW where it is amplified up to the RRx, which converts it into a digital signal that is then converted in the System Cabinet to useable data seen on the operator monitor.
Safety
| Warning | |
|---|---|
Laser Radiation Hazard! Invisible laser radiation can be emitted from disconnected
fiber-optic cables or connectors. Do not stare into the beam, point the cable or connector
ends at your eyes, or view through optical instruments. | |
| Notice | |
|---|---|
Electrostatic discharge (ESD) can cause permanent damage to electronic components. Observe the following ESD precautions: Wear a static wrist strap to ensure that any accumulated electrostatic charge is discharged from your body to the ground. Create a common ground for the equipment being worked on by connecting the static-free mat, static wrist strap, and peripheral units to that piece of equipment. | |
| Notice | |
|---|---|
The SFP optical transceiver is very sensitive to ESD. SFP latent failures can occur, in dry climates or low relative humidity, surpassing their ESD protection. Contaminant failures can occur in SFP optics and exposed glass Rx and Tx cable ends. Do not touch the exposed ends on fiber connectors. Leave the dust caps in place until you are ready to install the SFP module. Use the Fiber Optics Cleaning Kit to clean both the SFP and cable end every time they are replaced or swapped from one port to another, or when using a loopback. When working with the SFP optical transceiver or SFP Loopback, also observe the following precautions: Always use ESD protection when handling the SFP optical transceiver to prevent early failure. Always keep a protective cap on unplugged fiber connections. The SFP must be shipped in antistatic packaging. Discard any SFP shipped or stored without proper ESD protection. For more information on handling and cleaning the SFP transceiver refer to Fiber Optic Cable Devices Installation and Replacement. | |
Input
MR signals are at 64Mhz for 1.5T and the signals travel on standard coaxial cables from the Multi-Coils through the LPCA to the Mega SW. The signals are converted to 16 Mhz.
Output
The 16 Mhz signal travels between the Mega SW and receiver module via 37 pin Sub-D cables. The Receiver Module RRx contains A/D converters that digitize each of the 16 receive channels, provides digital tuning, pass band filtering and formats the data for transfer out of the scan room over a high-speed fiber optic link.
