AMiBA Engineering Telecon Minutes

21, Feb, 2002

Chair: K.Y. Lo

Participants: R. Martin, J. Peterson, D. Kubo (USA)

H. Wang, T.D. Chiueh, M.T. Chen, Y.J. Hwang, H.M. Jiang, W. Ho,

C.J. Ma, K.Y. Lin, P. Shaw (Taipei)

Summary

Correlator:

1. We should start by figuring out what our most important goals are for the correlator and try to save as much as work we have done so far. If we relax the band width requirement up to10 GHz instead of 20GHz, that might make much things simpler, to get 20GHz to get two of them. That might be far more feasible way than insist on 20GHz band width as one goal.

Fred suggests that's the direction we need to think harder about, and discuss more general direction and have people go through more detail to spread out the trade off thoughts. Jeff will look into the possibility of the no lag complex multiplier approach. Fred suggests to set up a separate telecon to go over more correlator issues a little bit more before March meeting at Taipei, at that time we really want to sort out issues more detail level instead of a general approach.

Besides, we need to go over the test report done by C.T. Li, and fully discuss the status of Rapadas' module and to see what we can improve on that design in a way we could actually afford to build the whole correlator. In some sense If we can do that then we much rather worry about improving on Rapadas' design than going to a complete new direction at this stage. Of course we want to see another relative approaches which not too big deviation than what we have just in case of doesn't work.

2.There is another issue we haven't paid much attention to is the signal distribution. Jeff thinks Andy Harris' proposal is a good plan in general. He will take care of that part lead the discussion as well, and Derek will lead the discussion on talking with Warwick over the test report on Rapadas' module. We need to have a separate telecon to discuss them before March meeting to focus the discussion a bit more so that at the March meeting we can make decision.

MMIC:

1. Huei got the non-linear model from TRW, but it doesn't look very good, so he decides to build our own model. He is aiming to finish all design and send to TRW by mid-march.

2. Huei, Fred, Bob and Paul had a telecon with Charles Rollence and Todd Gaier this Tuesday to discuss the collaboration of JPL/ASIAA on packaging and testing. Todd will come out a cost estimation of building 28 LNA for AMiBA by this summer in a day or two.

3. After the AMiBA site visit in early Feb, the President of Chung Shang Institute, Dr. Lieu has a micro wave engineer background and understand what we are doing , actually he is very excited and mobilizing some things in his institute. They like to help out. We need to figure out the details how they can help.

Site:

Bob sent out the site pictures around, there is an existing pad and small dome near the MLO site. We can use it for prototype and put some small electronics in there. There are already electricity power outside, and Bob needs to find out is there a three phase power source.  That site has a good view to the south, east and west, someone blocks the north, but t doesn't matter anyway for prototype. It sounds like the paper work on MLO will go on for some time, the their attitude is go ahead to start putting stuff there and worry about paper later. We need to set up a schedule for site activities, and this should be pinned down in the March meeting. Bob will follow up to draft out an agenda accordingly.

Hilo Lab:

Bob has sorted out leasing problem with CSO, now we had space start using, but the formal mechanism not in place and need more time to proceed. Mingtang will go there and take a look at the lab next week.

Vertex mount:

Bob sent out our comments on the Vertex document and asked for setting up a telecon with them on Friday or next Monday as well.

Receiver:

Mingtang

30cm dish:

The dish in Tucson is still waiting for re-measuring, the other one in Taipei will be tested together with receiver ASAP.

60cm dish:

We had three quotes in our hand, they are very different in price. Milliflect has a different design in feed lag and without shield. We need to set up a separate telecon to talk about the details.

Platform:

Philippe is in Taipei, he is working on the modeling almost half way now.

Action Items:

1. Paul/ Derek/Jeff Paul will arrange a telecon on next Tuesday morming (Taipei time) for Fred, Bob, Jeff, Derek, Warwick, C.T. to discuss the correlator issues. Derek will lead the discussion on the test report of Meridian lag correlator, and Jeff will lead the discussion on the signal distribution issue.

2. Jeff/Bob Jeff will check whether he can provide a test hexapod mount for us to use in order to gain some experiences in operation. In the mean time, Bob will find out how are things going about the 2m hexapod mount of the optical telescope in Germany.

3. Mingtnag/ Mingtang will find out whether a single phase power is okay to operate the receiver prototype at site.

4. Philippe/Paul     Philippe & Paul will arrange a telecon for Bob, Mike, Jeff in the next week to go over the issues of 30cm & 60cm dishes.

5. Bob/ Bob will discuss with Paul to set up an agenda to go over the prototype plan and work plan 2002 as well in the March 6 meeting.

6. Bob/Philippe/Mingtang/T.H.Chu/Warwick/Honmingl/ The work plans 2002 for each work package should be drafted out and sent to Paul by end-Feb, so that we could go over together in the March meting.

!!! Next meeting: Thursday, 7, March at 8:30AM Taipei time !!!