NAOJ GW Elog Logbook 3.2
Took a pic of two LED candidates:
- OP232 (the golden one)
- TSTS7100 (the silver one)
The packages seem similar forms, but be careful, positions of the anode and cathode are opposite!! to the flange's boss.
Please check the following files showing the modifications of OSEM LED and PD holders for PR2 and PR3 (hope - only) . The concept is that using already exisiting parts as far as possible anyhow!
The design will be checked by VIS people, and then a few test parts will be purchased.
Some parts of the LED assy and all parts of the PD assy have compatibilites with new (unapproved by VIS still) design of OSEM LED/PD holders in the following.
Hope they are approved immediately, and then I'd like to start with purchasing a few samples. I have already got some cost estimations from several companies and started comparison.
The reason why some parts have JGW-Dxxx, but others not is, I guess, there would be some difference in the concept for controlling things between VIS and me.
Torii-san has created a conical baffle for cutting down the ghost beam. We readjusted the scatterometer and Torii-san is again measuring the DLC sample. We will see whether the asymmetry in the data is still there or not. If yes, I guess its origin in the multiple reflections of the beam splitter.
and asked the manufacture company about the cost reduction.
Those parts are for box structres of IM and IRM.
Hope the oreder can be done soon (in low cost!)...
Some information
http://www.zairyo-ya.com/info/zaisen_tebiki_2.html
http://www.labnotes.jp/pdf2/aluminum.pdf
http://www.toyo-success.co.jp/product/characteristic_a.html
http://fa.misumi.jp/product/plate/prty.html
Meeting
About a TMS's vibration isolation system, I (and Aso-san) had a meeting with some Japanese agents of the company A today.
The vibration isolation system is an active/passive VIS leg (of course vac compatible, they said).
For example, an idea of the application is that those three legs would support an optical table for the TMS.
To do
In the next week, I will send them more detailed and compiled information of the TMS including foreseen its structure, and then they can start the cost estimation.
and asked the manufacture company about the cost reduction.
Those parts are for box structres of IM and IRM.
Hope the oreder can be done soon (in low cost!)...
Some information
http://www.zairyo-ya.com/info/zaisen_tebiki_2.html
http://www.labnotes.jp/pdf2/aluminum.pdf
http://www.toyo-success.co.jp/product/characteristic_a.html
http://fa.misumi.jp/product/plate/prty.html
From a paper from Toukoku-san (2014), I have calculated the maximum magnetic dipole moment of solblack. It is 6*10^-5 Am^2.
From this, I have rerun the program and calculated the maximum influence of a magnetized wide-angle-baffle (non-suspended). The results can be seen in the graph attached to this report.
Torii-san has measured the DLC sample and discovered a small unsymmetry between "positive" and "negative" angles.
I will try to search for en explanation.
Regarding the ghost beam. Torii-san wants to create a conical shaped baffle (blackend by candle-soot) to avoid an influence of ghost beams and, at the same time, keeping the symmetry. I think that the ND filter is in a first glance OK and we should focus on the sample holder for solblack. After this, we can think of this baffle.
Today, the enclosure of the compressor for the cryostat at the ATC was installed. It is a very tall one indeed.
The actual installation of the cryostat will take place on 26 and 27 of March.
Summary:
I soldered long pins to the geophone pre-amps to be used for the TAMA prototype test. I also made an adopter cable to convert the amphenol MIL-C-24682 10-6 connector to a D-SUB 9 so that we can connect the geophone output to the digital system.
I made three pre-amp circuits and one conversion cable. The next step is to connect the pre-amp to a geophone and connect it to the digital system through the converion cable to see if this chain of signal flow works or not.
Details:
Pre-amp circuit issue:
There are 6 pins sticking out on the pre-amp PCB. These were soldered during the in-air tests and the pins became unusable. These are ITT/Cannon 031-9074-002. I ordered 20 of them. When I got these, I found that the pins had a thick section at the end, which prevented them from inserted into the holes on the pre-amp PCB. After consulting with Okada-san of ATC, I decided to cut those unwanted section with lathe. It was a fun since it had been a long time since the last time I used lathe :-) After the machining, I soldered those pins into the pre-amp circuits.
Conversion cable:
The output from the air-tiight container (vacuum pod) of the geophone is Amphenol MIL-C-24682 10-6 (6-pin) (http://www.mouser.com/ds/2/18/26482_10-469475.pdf).
We need to make a conversion cable from Amphenol to D-SUB 9 as suggested by Mark's cabling document (http://gwdoc.icrr.u-tokyo.ac.
Amphenol <- Flat twisted pair cable -> D-SUB
(A) +14V <- Brown -> D-SUB pin 9
(E) and (F) are twisted.
Next step:
We should connect them all (including soldering of geohone output cables to the pre-amp PCB) and check if the signals are as expected.
Concerns:
Although I tried to keep the flange of the vacuum pod as clean as possible by putting on latex gloves, I think the flange and the cable, which are supposed to be put into vacuum, are not so clean. We need to clean them before installing. Also I wonder how the cables will be assembled for real KAGRA.
Resources (compiled by Mark):
(B) SIG RET <- Red -> D-SUB pin 2
(C) POWER RTN <- Orange -> D-SUB pin 5
(D) +14 <- Yellow -> D-SUB pin pin 4
(E) OUT P <- Green -> D-SUB pin 1
(F) OUT N <- Light Grey -> D-SUB pin 6
http://gwdoc.icrr.u-tokyo.ac.