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Chapter 5. Wideline Module Tests
32
UNITY
INOVA Solids Hardware Installation 01-999044-00 C0501
2. Enter the following parameters to observe the transmitter pulse along the transmitter
pathway:
nt=1e5 pw=100 dm='n' rof1=30 rof2=0.2 alfa=0
sw=1e5 at=0.001 tpwr=63
.
3. On the solids cabinet control panel (see Figure 7 ), set the LO BAND switch to
HI POWER . Enter
go
.
4. Confirm that the transmitted signal level at J25 rf input on the AMT M3201 is 54
dBm or less.
5. Halt the acquisition with
aa
and replace the cables.
Testing the Solids Observe Transmitter RF Signal Path
1. The broadband amplifier requires no tuning but must be properly terminated by a 50-
ohm load at all times. To verify its operation, switch the LO BAND to HI POWER
and observe the rf using a 500-W, 30-dB attenuator and additional attenuation as
required. Check the output at the magnet observe port as described in steps
5 and 6
below.
2. Confirm that the blanking gate cable is connected as described below for the
appropriate amplifier and required gate logic.
3. Turn on the AMT amplifier at the front panel and check that all interlocks go out.
Only the light labeled POWER should be lit. If the status lights labeled PULSE
WIDTH and/or DUTY CYCLE are lit, move jumper J2 on the Solids Relay Driver
board to short the middle and bottom pins.
4. Confirm that the minimum full power output in the pulsed mode is 1 kW (60 dBm).
This should not require adjustment of the amplifier gain.
5. Observe the pulse shape using a 8-ms pulse width. Do not confuse the rf pulse rise
and fall times with the amplifier turn-on time of 15 µs and turn-off time of 3 µs. The
pulse droop for an 8-ms rf pulse would be 3% or less.
6. Confirm the absence of any amplifier gating/blanking transient pulses coincident
with the external amplifier gating signal.
Decoupler Transmitter Performance
Confirm that the decoupler transmitter output to the probe normal as for liquids high band
when the amplifier switch is in the LO POWER position. The decoupler should perform as
HI BAND
CW
PULSE
TEMP
DUTYCYC
P WIDTH
OVER DR
LO BAND
CW
PULSE
TEMP
DUDTCYC
P WIDTH
OVER DR
OFF ON
SHUT OFF CAUTION
LO
POWER
HI
POWER
HI
POWER
PLATE
CURRENT
GRID
CURERENT
- + - +
LO
POWER
HI BAND
LOBAND
STATUS
HI POWER ENABLE
AC
POWER
Figure 7. High-Power Amplifier Control Panel on Solids Cabinet