Aloka ProSound Alpha 10, Service Manual, Page: 114 / 405

MN2-2008, Rev.2
SECTION 4 Principle of System Operation
4 - 81
4-4-2
Tx/Rx unit
Tx/Rx unit consists of;
Probe Connector part
Tx/Rx part
Digital Beam Former part
Beam Processor part
In addition, the following module/unit are installed in Tx/Rx unit.
Independent probe connection unit: EU-9110
(Option, Ver.3.0.0. and higher)
Mechanical scanning probe connection unit:
EU-9109
(Option, Ver.4.0.0. and higher, M01705 and before)
EU-9124
(Option, Ver.4.0.0. and higher, M01706 and after)
Probe Connector part
It has connectors for electric probes (Phased array, Linear, Convex, Compound array, VOL
scanner and Motorized TEE probe).
Probe Selector board is equipped with HVS (High Voltage Switch) that select the channels
of transmission from the entire transducers when Linear/Convex probe is connected. This
board controls the HVS as well.
Unlike conventional machines, SSD-ALPHA10 doesn’t require a control cable for VOL
mode scanner and Motorized TEE probe since those controls have been included in the pin
assignment.
Furthermore, SSD-APLHA10 adopted new ID for probes that includes not only probe
code but also serial number of the probe. This ID is planted in the probe connector and a
machine reads out the information from it.
It is possible to connect conventional probes as well.
Tx/Rx part
SSD-ALPHA10 adopted different transmission method from conventional machines that it
transmits ultrasound by applying not a single pulse but a waveform. The data of Tx
waveform, focus, apodization are kept in the HDD and it is transferred to the memory of
Tx Generator, calculated in accordance with the condition of Tx/Rx setting. The Wave
Generator creates Tx waveform processing those data then passed to electric probes.
This method makes it possible to create variety of waveform based on sine curve
Received echo is amplified by Pre Amp. in Wave Generator and then, passed to TGC Amp.
in Front End Controller in order to adjust the signal level to the A/D converter at the input
of the Rx Beam Former.
In the case of STCW, the Wave Generator do the transmission in the same way. The
waveform is generated repeatedly so that it makes continuous transmission. The echo
signal is amplified by the Pre Amp. And then go through the quadrature detector in Wave
Generator. Then it passed to A/D converter in Mech. Front End and transferred to Beam
Processor 1.