Development of Recent STFRF

1
Development of Recent STF-RF

• S.FUKUDA

? Evaluation test of L-band klystron TH2104A of
JHP ? Image drawing of PDS (Waveguide System) ?
Status of First Modulator (Revised plan of PNC
Modulator) ? LLRF?by Michizono in next.
2
JHP Klystron TH2104A

• TH2104A was purchased in1984 for the JHP project
  Rating of 1.296GHz, 5MW,
  600 ms,50pps.
• After the fundamental test, it was quit using at
  1993. It has been stocked in the KEK storehouse.
• Since the delivery time of new klystron (TH2104C,
  5MW) is about 11 month, we want to use the old
  TH2104A at first.
• cost saving (0.3 million for a tube).
• It is necessary to confirm the klystron operation
  ability, such as heater, cathode activity, and
  power capability.
• No long pulse modulator up to December.
• Many short pulse modulator for S-band system-gt
• This system is used for the performance
  testing of the klystron.

3
Performance test(1)

• Cathode Activity Test
• (applying dc 1kV to take an emission)

Socket for the TH2104
Thares Adapter and Spring contact socket Will
be adopted.
DC 1kV Emission test bench
Perveance for 1kV Is OK
4
Performance test(2)
No SF6 gas fill Test is limited for The
repetition of 1hz. PFN Matching was adjusted
for the lower voltage Application such as less
that 140kV. (This modulator Has a capability Up
to 500kV)
Schematic draw of the testing
Actual system of testing
5
Voltage Waveform (top) and Current waveform
(bottom)
6
High Voltage Operation Data
Output power with the function of Applied voltage
Output power with the function of Input power
Strictly speaking there are some discrepancies
from the old data. But old data was lost and
detail comparison was difficult. TH2104A is
confirmed to be operatable in STF-RF source.
7
Bird eye view of PDS in klystron gallery.
Variable short
8
PDS in tunnel
9
Pulse transformer and tank size was determined