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We are able to see mean differences of about 700 mV as shown in Bens spice simulations. Though only when measuring at R26 later at the Kapton Flex the general signal amplitude has lowered.


2020.02.12, 20 Ohm modified resistor (ERROR: RESISTOR IS ON TRIGGER PINS NOT CLOCK PINS THEREFORE OBVIOUSLY NOTHING CHANGES ON THE CLOCK SIGNAL)

The cassette board was modified by adding a 0201 20 Ohm SMD resistor on top of the Kapton Flex connector on the board between pins 34 and 36 which correspond to the clock lines of the left KPiX.

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By mistake the pins 10 and 12 which correspond to the clock lines of another KPiX were not equipped with a 20 Ohm resistor. Though this can be used to study the effect of the 20 Ohm resistor on the clock dampening.

Based on Bens spice simulations this resistor should dampen the clock peak to peak down to 100 mV.

When probing it with a single high ohmic probe on the Kapton Flex the results are not as expected.

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This picture shows the clock signal on the supposedly dampened KPiX 1 location

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While this picture is on the non dampened connection. As one can see there is basically no difference. The picture show on the other hand that the resistor was placed correctly.

Furthermore, measurements of the line resistance give the following results when measuring between pins 34 and 36 with the Kapton Flex connected we get a resistance of 15 to 16 Ohm which can be calculated by

1/R34-36 = 1/R1 + 1/R2 + 1/R3

While when measuring between pins 10 and 12 we get a resistance of (TODO)

Where R1 is the newly added 20 Ohm resistor, R2 is the 100 Ohm resistor on the Kapton Flex and R3 is a generally measured resistance between the pins when no Kapton Flex is connected. I.e. the on board resistance.

R1 = 20 Ohm

R2 = 100 Ohm

R3 = 700 Ohm (question) Was measured but I am not sure if it is correct

When calculating R34-36 we get as calculated resistance 16.27 Ohm which seems to indicate that our measurement is correct.

this was an error from uwes side as those are the trigger pins not the clock pins. The pictures are still nice but no conclusions should be drawn from any measurements.

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