Setting The Dose Rate For Zoom Format; Concluding Steps - Siemens SIREMOBIL Iso-C Troubleshooting Manual

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X
Apply fluoro briefly until the generator finishes regulating the automatic fluoro adjust-
ment.
Select KV STOP at the system operating console.
Switch on fluoro.
Set the dose rate with the [+kV] and [-kV] keys. (Dose rate * grid correction factor).
The resulting KV value should be between 70 to 80 kV. If necessary, change the prefil-
tration and set the dose rate again using keys [+kV] or [-kV]. Refer to the table.
Switch off fluoro.
Remove the dose measurement chamber from the I.I. input screen.
X
Switch on fluoro.
Press the [>0<] at the system operating console. This starts the automatic adjustment
procedure for the TV-iris collimator.
Wait until the message "done" appears in the "AUTO REGULATION" line.
The "BRIGHTNESS DEVIATION" value is shown in the "BRIGHTNESS DEVIATION"
line and should be 0 ± 3 .
Switch off fluoro.

Setting the dose rate for zoom format

also see the note in the previous section *
KV-STOP remains selected.
Center the dose measurement chamber on the I.I. input screen and attach.
Select the I.I. zoom format (refer to "I.I. ZOOM STATUS"). The KV values remain the
same. The mA values, however, are automatically increased by a factor of 1.41.
Use the [mA+] and [mA-] keys to set the dose rate for the zoom format (dose rate *grid
correction factor).
Press the [>0<] key on the system operating console. This starts the automatic adjust-
ment procedure for the TV-iris collimator.
Wait until the message "done" appears in the "AUTO REGULATION" line.
The "BRIGHTNESS DEVIATION" value is shown in the "BRIGHTNESS DEVIATION"
line and should be 0 ± 3. Also see the note on the previous page *
Switch off fluoro.
Select the next level of dose rate (LOW / MID / HIGH) and repeat the dose rate setting
for the survey and zoom format for this level.

Concluding steps

After setting all dose rates for the survey and zoom formats, click "Stop Update" and
wait until "CAL" disappears from the 7-digit indicator on the right-hand side of the oper-
ating console. The TV- iris collimator values are stored to the EE-PROM of the host.
Press ESC on the service PC to return to the main menu.
Select the "Data, Backup..." menu.
SIREMOBIL Iso-C SPR2-230.840.01.01.02
08.08
Adjustments / Programs
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