Changes

'''If the electronics are powered and the dark box is open, the siliconphotomultipliers WILL be damaged''', so it is very important to make sure electronics are off before the dark box is opened.   

'''If the electronics are powered and the dark box is open, the siliconphotomultipliers WILL be damaged''', so it is very important to make sure electronics are off before the dark box is opened.   

[[Fiber QA Troubleshooting]]

We made our testing darkbox from scratch so we had to configure electronics and troubleshoot issues with the Fiber QA Procedures. You can read the details of these effors on the [[Fiber QA Troubleshooting]] page, but they are summarized below:

Fibers will be issued a new name after QA consisting of a Roman Numeral for the bundle which they are from, followed by a number in parentheses which designates it's position within the bundle. The diagram below shows how the fibers are positioned as viewed from the light guide/SiPM side of the fibers. These are also how the histos are going to appear in the analyzer.

Fibers will be issued a new name after QA in the form of a bundle number, followed by a colon and then a fiber number. The diagram below shows how the fibers are positioned as viewed within the fibers, looking from the light guides out through the SciFis. [[File:LH-FiberTesting-QANomenclature.png|275px|center]]

[[File:LH-FiberTesting-QANomenclature.png|275px|center]]

==Procedure==

==Procedure==

[[File:LH-FiberTesting-CleanRoom.jpg|thumb|right|upright|The ventilated clean room with a workbench, the dark box, and all necessary electronics.]]

[[File:LH-FiberTesting-CleanRoom.jpg|thumb|right|upright|The ventilated clean room with a workbench, the dark box, and all necessary electronics.]]

*Before taking any fibers out of the dark room, open the [https://docs.google.com/a/uconn.edu/spreadsheets/d/1T4NUSQO_keT0QckCx4rWlbMW7Yot4vb-Z1eqrM1l94k| Fiber QA] Google Doc. Each bundle has a separate tab which you can view the alignments required for each run.

*Before taking any fibers out of the dark room, open the [https://docs.google.com/a/uconn.edu/spreadsheets/d/1T4NUSQO_keT0QckCx4rWlbMW7Yot4vb-Z1eqrM1l94k|Fiber QA] Google Doc. Each bundle has a separate tab which you can view the alignments required for each run.

*Before selecting fibers from their dark room, don a pair of powder free gloves and place the popsicle stick with the testing clamps at the table you will be working.

*Before selecting fibers from their dark room, don a pair of powder free gloves and place the popsicle stick with the testing clamps at the table you will be working. Also grab 3 kapton strips from the kapton strip box along with accompanying bolts and washers.

*Note which fibers are to be tested during the run and take only those fibers out of the dark room.

*Note which fibers are to be tested during the run and take only those fibers out of the dark room. The fibers not attached to a popsicle stick are sorted by bending bundle name.  

*If no meeting is going on in the conference room, bring the fibers in there and turn off all the lights.  

*If no meeting is going on in the conference room, bring the fibers in there and turn off all the lights.  

*Continue this process with the remaining columns.

*Continue this process with the remaining columns.

*Once the fibers are in the order they belong, begin placing them in the clamp on the popsicle stick.

*Once the fibers are in the order they belong, begin placing them in the wide clamp on the popsicle stick.

**This step will take two people.  One person should place the fibers, while the other should hold them in place once they are placed.  This way fibers will stay in their appropriate positions.   

**This step will take two people.  One person should place the fibers, while the other should hold them in place once they are placed.  This way fibers will stay in their appropriate positions.   

[[File:LH-FiberTesting-PopStickClamp.jpg|thumb|center|upright|The popsicle stick with clamp and wires to hold the fibers in place. We're working on a different model which would use mylar to hold the fibers down.]]

[[File:LH-FiberTesting-PopStickClamp.jpg|thumb|center|upright|The popsicle stick with clamp and wires to hold the fibers in place. We're working on a different model which would use mylar to hold the fibers down.]]

*Loosen the clamp and move it down over the fibers.  Tighten it enough so they do not slip but not too tight as to make it impossible to add paper spacers in the near future. Also use the wires that are going through the holes in the popscile stick to your advantage.  Tightening them around the fibers will do a good job of keeping the fibers in place.

*Loosen the clamp and move it down over the fibers.  Tighten it enough so they do not slip but not too tight as to make it impossible to add paper spacers in the near future. Also use the wires that are going through the holes in the popsicle stick to your advantage.  Tightening them around the fibers will do a good job of keeping the fibers in place.

**The fibers do not have to be flush with one another at this point.  The next step, putting in paper spacers, will move them out of alignment anyways, so do not waste time on a step that will have to be repeated.

**The fibers do not have to be flush with one another at this point.  The next step, putting in paper spacers, will move them out of alignment anyways, so do not waste time on a step that will have to be repeated.

*The next step is to put spacers in the middle of the s-bend in the fibers for both columns and rows.   

*The next step is to put spacers in the middle of the s-bend in the fibers for both columns and rows.   

*Now it is time to make the face of the scintillating fibers flush with one another.  This job also takes two people.

*Now it is time to make the face of the scintillating fibers flush with one another.  This job also takes two people.

**One person should be holding a rigid piece of material along the popsicle stick where the fibers protrude while another person goes through each fiber and one by one pushes it in to the material.   

**One person should be holding a rigid piece of material along the popsicle stick where the fibers protrude while another person goes through each fiber and one by one pushes it in to the material.   

*Once each fiber has been pushed into the rigid material, the fibers should be held in place by twisting the wire tightly around them.  The rigid material should be carefully moved away to determine if the fibers are flush.  If not, repeat the process again.

*Once each fiber has been pushed into the rigid material, the fibers should be held in place by re-tightening the metal strap and adding the kapton strips.  The rigid material should be carefully moved away to determine if the fibers are flush.  If not, repeat the process again.

**Kapton strips should be placed around the "up-stream" bundle and around both bundles at the end of the popsicle stick.

*After you are sure that the fibers are properly separated and flush with each other, make sure the wires and clamp is tight so that no fibers can change position.  

*After you are sure that the fibers are properly separated and flush with each other, make sure the wires and clamp is tight so that no fibers can change position.  

*'''Check that all electronics are off before opening the dark box! Have a grad student or lab technician remove the board after opening the dark box.''' Carefully unscrew the main dark box opening and dock the popsicle stick into place by tightening the two screws underneath the popsicle stick to secure it into place. The wood has been depressed in the place where the popsicle stick should be. '''Do not modify the position of the pulsar at any point during the loading process!'''

*'''Check that all electronics are off before opening the dark box! Have a grad student or lab technician remove the board after opening the dark box.''' Carefully unscrew the main dark box opening and dock the popsicle stick into place by tightening the two screws underneath the popsicle stick to secure it into place. The wood has been depressed in the place where the popsicle stick should be. '''Do not modify the position of the pulsar at any point during the loading process!'''

{|style="margin: 0 auto;"

{|style="margin: 0 auto;"

| [[File:LH-FiberTesting-Pulsar1.jpg|thumb|center|upright|Image of the fibers, mirror and pulsar from the main opening of the dark box.]]

| [[File:LH-FiberTesting-Pulsar1.jpg|thumb|center|upright|Image of the fibers, mirror and pulsar from the main opening of the dark box.]]

| [[File:LH-FiberTesting-Pulsar2.jpg|thumb|center|upright|Image of the fibers, mirror and pulsar from along the fibers.]]

| [[File:LH-FiberTesting-Pulsar2.jpg|thumb|center|upright|Image of the fibers, mirror and pulsar from along the fibers.]]

|}

|}

 

*Guide the fiber ends over the edge and using the Google Document, place the fibers into the chimney in the correct order. '''Have a grad student or lab technician check the fibers at this step. The fibers cannot be too far into the chimneys or else they will damage the SiPMs when the board is replaced. A grad student or lab technician must put the SiPM board back into place.'''

*Guide the fiber ends over the edge and using the Google Document, place the fibers into the chimney in the correct order.  

*'''Have a lab technician check the fibers at this step.''' The fibers cannot be too far into the chimneys or else they will damage the SiPMs when the board is replaced.  

*'''A grad student or lab technician''' must put the SiPM board back into place. Do not just use your thumbs to push in the pre-amp boards as it may bend the backplane. Gently slide the board into place and screw in the chimney support until it is flush against the chimney.

[[File:LH-FiberTesting-InsideDarkBox.jpg|thumb|center|upright|View of the fibers from the main opening of the dark box. Black plastic separates the scintillating fiber end and pulsar from the chimneys and SciPMs.]]

[[File:LH-FiberTesting-InsideDarkBox.jpg|thumb|center|upright|View of the fibers from the main opening of the dark box. Black plastic separates the scintillating fiber end and pulsar from the chimneys and SciPMs.]]

*Close the main dark box opening and ensure that it is light sealed.  

*Close the main dark box opening and ensure that it is light sealed.  

*Turn on the electronics and begin the fiber test.

*Turn on the power supply for the pulser and the op-amp first. Check that the voltages remain constant at 1.5 V and 10 V. Next turn on the power supply for the pre-amps and backplane electronics.

 

**It takes 7-8 minutes from the time the run begins to complete. If the run does not finish in this time, something has gone wrong. Notify a grad student.