Changes considered for production tubes.

Remove resistors between the final dynode stage and the anodes, R18 - R33.

This is to be compatible with QIE/SMQIE.

Charge-up problem?

SMQIE has to determine the ground level and thus the anode level. Cause a difference from the HV ground?

Add a 300-Ohm resistor between HV shield and anode shield?

Anode pin output instead of cables. Like one in H7546 (64 ch), but with individual ground pins.

H8711 drawings : 1 - 2 (HV is also a pin), 3 - 4 (HV coax cable)

Use the tapered voltage divider for a factor of 10 better pulse linearity (dynamic range).

The ratios will be 1.5 : 1.5 : 1.5 : 1 : 1 ... 1 : 2 : 3.6.

This should ease the space-charge effects at the last synode stages,

though the overall gain will be reduced by roughly a factor of 5 (at -800 V).

Design proposal : Sept 2002
H8711A-10MOD drawings : Electrical - Mechanical

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Oct 17, 2002. Order placed for ten H8711A-10MOD tubes.
To be shipped from Hamamatsu to Tsukuba on Dec 20, 2002.
Final drawings: Mechanical - Electrical

Delivered on Dec 24, 2002.
Tube data by Hamamatsu: Data sheets - Anode uniformity - Mechanical drawing - Electrical drawing

Pictures: (including the interface PC board prototype)

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Real size of the anode pixels (Aug 30, 2002)

PMT box design as of Nov 2002 (from Bob Miller, MSU)
And a matching HV connector candidate 11 SHV-50-3-1 on the PMT side.

Nov 14, 2002 :
A further modification of the pins is being asked so that we can attach TSW-type connectors
(e.g. TSW-108-07-?-D) on the PMT.
This is under consideration by Hamamatsu.

Feb 14, 2003 :

H8711A-10MOD (21B-030A) drawings : pdf file

(both mechanical and electrical, though no change to electrical)