1. We need to go ahead to purchase the first four units of HPF now, otherwise we will not get them by June. Leo will raise the purchase request right after meeting, and in the mean time he should clarify the timing for placing the second order is within months after receiving the first four units.
2. Regarding the possibility to use the JPL or U Mass’ design, Fred will pursue on contacting Challis Lawrence to see what he can do. As per Fred’s request, Huei will arrange a telecon with Todd and Challis Lawrence to sort out this issue as soon as Fred coming back.
3. Regarding the self- grant proposal to NSF for acquiring InP HEMT & InP HBT chips with JPL or UMass design. Bob will discuss it offline with Jeff by tomorrow.
4. Leo says that a mixer and an amplifier had been sent back to Spacek for thorough adjustment.
5. Eugene says that the Chungshung Institute has tested the Sub-harmonic mixer, but the result is much worse than the test result of AT. Eugene will follow up and sort out this problem with Chungshung Institute.
6. Fred suggests to set up a separate meeting to go over all of the MMIC issue, which including the time scale for construction, what risk involved for the packaging, the price and so on.

H.C.Lu

K.Y.Lo
H.Wang

Bob Martin

H.C. Lu

Y.J. Hwang

B.Martin

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1. Regarding the phase switch, Leo found some solid stats switches of Miteq they can operate at 14 GHz with switch speed up to 20 nano second; he thinks it quite sufficient for switching the phase at 14 GHz.
2. Warwick says that they have been a bit look at other approach; one of them is the Silicon Gemanium. There is one company, they have a new silicon gemanium process coming up with 70GHz, and it probably is ok. And the pricing is if we order $20KUSD, and will get us 10 samples of circuit abroad the size we need for multipliers. It is something they should look into, it’s a fairly small atelier to do the development in that area and see how we go. We probably get something back in 6 months or so. Warwick just starts talking with them now, and will sign a NDA with them very soon. Warwick will send that company information to Huei.
3. Bob will set up a separate meeting with Jeff and Warwick to go over the correlator issues after Warwick back.
4. Warwick will come here on April 25 to participate the MoE site visit.
   Jeff sent a version of design to Warwick, and exchanging information each other on the circuit design of correlator. He has ordered all components, and waiting for components back, it should be arrived in a month from now, and then assembling the mixers for two weeks and test them for another two weeks. In the mean while, Jeff is preceding a further test of a single mixer, looking for a low frequency noise. And he think they may succeed to reach the level of sensitivity for AMiBA, its quite challenge since they need very quiet amplifier following to do the test well. But so he didn’t seed any low frequency noise even down to 100 Hz. Warwick did some tests with a mixer as well, the mixer they just happen to have, and its noise is extremely low, and below the AMiBA sensitivity requirement. So at least we have two mixers available, and we need to wait for the final product for prototype to test with actual diagnosis been using in production.

W.Wilson

W.Wilson

B.Martin 

H.Wang
J.Peterson

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1. Mingtang will raise a purchase request for two sets of feed horn, the supplier – Thomas Keating in UK is the lowest quote from reliable sources. Price is 1,100 pounds for two, delivery in 9 to 11 weeks.
2. Jeff got two price quotes for fabrication two prototype of 30cm aperture horn-lens antenna; he also made a simple sketch. The Princeton University shop made a horn for MAP satellite; the price is around $17K USD for two prototypes. The other company made antennas for DASI, J & E in Massachusetts is interesting in production, they quoted $13KUSD for the two prototypes, and then not more than $2,900USD each for production, and 6 weeks in delivery. He will forward the quotes and sketch to Mingtang and Mal. Mal will follow up to see if he can get a beam pattern analysis to see how accurate we can simulate the lens.
3. Regarding the modeling on the circular polarization, a Mal will send a report around to everyone to look.
4. Regarding the loss calculation program for the whole system, Mal will help Leo update the calculation table through email.
5. Regarding the NRAO OMT production schedule, they are producing two prototypes, and will be delivered in July, and then test them. If everything goes well, they will produce one each per month. So by August is the earliest date we can get the OMT from NRAO.Bob will go over the shop and look at those stuffs on this Friday, and see how to speed up the production process. In the mean time, Mingtang will collect the update drawings and ask the Chungshang Institute to do it.

M.T.Chen

J.Peterson
M.Sinclair

M.Sinclair

H.C.Lu
M.Sinclair

B. Martin
M.T.Chen

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1. Eugene is collecting more data for manufacturing an alternative for the optical fiber.
2. Regarding the optical amplifier, Eugene is trying to calculate the system for the photonic LO without optical amplifier according the power level and noise level.
3. Eugene says that the essential test instrument will be delivered by end April, and will start to work by mid May or end May after training. And presently, he is working with Homin on modification of the optical PLL circuit from SAO design.

Y.J.Hwang
Y.J.Hwang

Y.J.Hwang

Ongoing
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Ongoing

1. Bob says that design study contract with Vertex is going on pretty well; most issues are sorted out for the hexapod mount design and start looking at the conventional design. They should have something by the end of April, to tell us the cost of those designs. And as for the construction time, they probably need 10 to 12 months after contracting either hexapod or conventional one. But it need more lead time to get some components for the conventional mount, e.g. the large bearings.
2. Bob will talked to the dish maker – CMA on this Friday to go over the program, and he think the two small dishes will be delivered by mid May. Now he is thinking how we check the accuracy, and start looking for a measuring firm. And another check we probably should do is the antenna range, he thinks this will be a good question for AT people, is there any range we can use or suggest something.
   There are two alternatives, one is in AT and the other one in Prof. Chu’s Lab, Mingtang says, but at this moment he is not sure how well the Prof. Lab’ lab equipped for our job. Leo will contact the person in charge the AT lab in order to get some information or suggestion on the lab. Mal will tell Leo whom he should contact.
3. Fred says that we need to consider having the 0.3m antennas surround the 1.2m antennas, and doing the correlation between 0.3m and 1.2m antennas. The advantage is that increasing the sensitivity perhaps. Ron has asked Ravi to study that more, and we also need to look into. Fred want to know is there any implication to platform. Bob will look at that in detail, he thinks it should be not a problem.
4. As for the large dishes, Bob has given the drawings to Philippe and talk together about in Boston also. Philippe will start the finite element analysis on the large dishes after back here.

B.Martin

B.Martin

H.C.Lu
M.Sinclair

B.Martin

P. Raffin

Ongoing

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H.M. Jiang

Ongoing