AMiBA Engineering Telecon Minutes

16, May, 2002

Chair: R. Martin

Participants: F. Patt, P. Raffin, T. Huang, P. Shaw (Hilo)

K.Y. Lo, H. Wang, T.D. Chiueh, M.T. Chen, C.T. Li, Y.J. Hwang,

H.M. Jiang, C.C. Han, C.J. Ma (Taipei)

Summary

Prototype integration test :

Mike has submitted a report to describe the tests on the full prototype interferometer. He summarized the main problems of the tests are system temperature high (160~260K over 85~106 GHz band), serious gain slop over the band (10dB), the effective is ~ 4GHz, serious 1/f noise.

He concluded that this prototype, as it stands, will be challenged to make any astromical obversations, with high Tsys, small effective bandpass and a further 30 degree degradation in signal to noise. For more details, please access the web site.

http://www.asiaa.sinica.edu.tw/amiba/priv/new/Integration_tests.html

Correlator:

Derek and C.T. made some tests on Marki M020676 biasable mixer, Mica mixer and correlator 1, they found  the Marki one has good responsivity , much lower output impededance than unbiased mixer and good squared term rejection. For more information, please access the web site.

http://www.asiaa.sinica.edu.tw/amiba/New/correlator/image/corr_mixer_eval%20051102h.pdf

http://www.asiaa.sinica.edu.tw/amiba/New/correlator/image/mbtp_summary.pdf

Receiver:

After integration tests, receiver group is working on modifying the IF configuration, checking where the excessive noise came from, and trying to figure out the serious gain slop problem.

60cm dish:

Jeff visited Miliflect to assess their ability to build 60cm dish. He wrote up a report and circulate to everybody to read and comment.  Bob thinks Miliflect dish is different with our specs, and we need to do modeling analysis on it.

Prototype mount:

Ted and Ferdinand have measured the pad for mount on site, they hopes to install the mount on site in a week or two.

Site:

Bob, Ted and Paul have surveyed the site together with Russ Schnell on Mauna Loa. Russ reconfirmed that we can use the existing pad on site for our prototype, and we pinned down the location for the final telescope.

Bob will come up with a site requirements and submit to MLO shortly, and MLO will help us to work out a detail engineering plan.

Action items:

for all/       The rehearsal for MoE site visit will take place on next Thursday starting at 10:30AM in room 716.

Speakers should follow up the agenda to prepare the presentation in PowerPoint file and send o Paul in advance. Mintang will give a talk on the AMiBA prototype explaining the goals and importance of prototype, ie to verify the design by real systems, important lesson we learned from the SMA, point out the valuable lessons we have learned already from the prototype.

for all/      As for the site visit, please update the poster according the latest data and send to Paul before May 21.

Bob/Philippe/Mintang     Bob, Philippe and Mintang will follow up to sort out the interface between platform and receiver, and modify the design and layout ASAP.

for all/        As for the 7 elements array review meeting in May 23, please send your PowerPoint file to Paul ASAP.

Next meeting:    Thursday, May 23, 8:30AM Taipei time.