ALMA WEEKLY PROGRESS REPORT 12th March 2004 Name: Jeff Mangum IPT: AEG ATF: (1) Work on both prototype antennas included: (i) VertexRSI: (a) Radiometry: Regular observations continue. Studying pointing, focus, and beam characteristics. (b) Optical Pointing: General OPT tracking and pointing studies complete. Implemented a change to the way the pointing model is implemented by bringing the pointing model calculation over to the ALMA side of the monitor and control system. This is a far superior solution (and the one that many of us argued should have been the way to go in the first place). This was made possible by some code which Pat Wallace provided. (c) OPT fast switching, offset pointing, and settling time measurements. Have a complete dataset waiting for analysis. (ii) AEC: (a) Contractor doing punchlist work. (b) Continued with early optical pointing runs. Contractor has finished default metrology system. (2) More document updates (ATF crib sheets, system descriptions, etc.). (3) Continue to chew-away on holography system description and results document with Jaap Baars and Robert Lucas. Name: John Effland IPT: Front End *** Major Issues: Software development effort continues as a major concern. Alex Grichener and I just estimated that we need 3.6 FTE's for software development of the FEIC Test system and to complete software for the Band 6 Test System. I continue to be concerned about delivery of the 300K cartridge plates. RAL received our suggested revisions three weeks ago but they haven't yet sent an updated version for final checking. Just today I left a message with and then e-mailed Mark Harman. Gene Lauria spoke with Javier Bautista of JPL, who is the engineer actually working with the Cryo-3 devices, and he said that Sam Petty is aware that an agreement is needed but Sam's battling funding cuts and our agreement is far down his priority list. Both polarization ports have now been measured in the first cartridge containing a real OMT but the second port shows an unusual noise spike at 260 GHz. That data were measured with the other polarization port loaded, and we now plan to place mixer-preamps on both ports and remeasure. *** Progress: *** Test System for Front End Integration Center Geoff Ediss released a draft analysis of the prototype pattern measurement system. I plan to ask for a significant amount of time from Miles Solatka to work on the tilt mechanism for the OVC. *** SIS Mixers The plating lab is now able to gold plate, and they already plated a huge number of mixer blocks and temperature sensor blocks. However, the goal posts require copper plating first, and I'm promised that it will be a short period of time before that capability is ready. *** Cartridge Construction The split shell is almost complete but requires holes drilled in the outer rings. *** Mixer-Preamps Both preamps with bodies modified to accept the bias cards were tested this week and they're matched acceptably well. ACC delivered the last preamp this week but it has not been tested. *** Cartridge Test System (CTS): The mixer-preamp and load were swapped to opposite polarization ports on the OMT but the second port shows an unusual noise spike at 260 GHz. The plan is to now place mixer-preamps on both ports and remeasure. Dan Koller submitted his modified loader design to the shop, which will allow a warm cartridge assembly and the cold side of the cartridge to be inserted into the cartridge test dewar. *** Mixer Test System (MTS): While attempting to test 13/09/15, we found that these early preamps from a prototype mixer still need 100 nF caps installed. The following lists mixer production status. Each number represents a mixer-preamp assembly: mixer/preamp_left/preamp_right: 13/09/15 - tests delayed until 100 pF caps installed in preamps (imperial mounting holes) 11/14/18 - tested, missing pole pieces, (imperial mounting holes) 12/21/22 - tested, now in cartridge test system 14/23/24 - assembled and ready for test 15 - no preamps available - used with load on input in cartridge. Alex Grichener held his design review for the mixer bias supply. *** Automated LO: No report. *** Software: Alex, Geoff, and I estimate we need about 0.7 FTE's to complete the Band 6 work and 2.9 FTE's to for software for the test set for the FEIC. This information was sent to John Payne, who will attempt to obtain more help. We still need someone to begin transitioning with Alex Grichener, who is scheduled to leave in mid June. *** Band 6 PDR: Everyone basically completed their viewgraphs for the Band 6 PDR and they were uploaded today onto ALMA EDM. We also completed and uploaded all the required documents. *** Tasks to be completed last week: 1) Complete measurement of noise and sideband performance of cartridge with OMT for both ports. Complete 2) Provide John Payne listing of software development requirements Complete 3) Complete measurement of mixer 13/09/15 Incomplete - preamps need modification 4) Complete bias supply design review Complete 5) Submit PDR documents to ALMA EDM Complete 6) Complete measurement of pattern measurement concept and write-up data and analysis. Incomplete *** Tasks to be completed next week: 1) Complete measurement of one polarization from cartridge with mixers on both ports. 2) Complete measurement of another mixer-preamp. 3) Measure the last preamp ACC sent to us and return results to them 4) Mount automated LO components on plates. 5) Get mechanical design help with FEIC tipping frame. ******************************************************************** Report from Gene Lauria IF amps: Mike Lambeth has completed two more amplifiers and they have been tested cold and are found to work as expected. These amplifiers have the 100nF capacitors mounted in the bias side of the amplifier. This was done because they are only available with soldered ends and cannot be connected with bond wires. We will be testing them for phase match when cooled on Friday. Device procurement: I spoke with Javier Bautista at JPL who is the engineer who has been giving us the Cryo-3 devices. I needed to ask him if I will be able to obtain devices so we can continue our production of our IF amplifiers, and told him the quantity that I will be needing for the whole project. He assured me that this should not be a problem, and he is going to bring this to Sam Petty who is the director of the group that has these devices so he can send them to us. Sam has not been in contact with us lately because he had to work on submitting proposals for his group, but Javier will speak to him directly and get back to me about fulfilling our requirements. Mixer testing: Unfortunately, this wasn't a productive week for mixer testing. We have mixer #13 paired up with our best matched IF amplifiers, but we weren't able to get the SSB source until Wednesday, and then we found that the connector to the mixer magnet broke. However, we now have the SSB source, and have fixed the magnet connector. We have started the cooldown Friday morning, and we will have results by Friday afternoon. We just don't have any results to report at this time. This test will determine whether the poor isolation seen in mixer #13 is related to the match of the IF amplifiers or if it is something related to the RF or IF hybrid. Lastly, I spent a lot of the week preparing for my talks on IF amplifier design and the mixer test system for the PDR which had to be submitted by Friday. I also cleaned up the documentation on the construction of the IF amplifiers for the potential vendor when they are ready to start construction. There have been many refinements to the documents and assembly procedures since they were first written and are now up to date (now in revision D). Work to do next week: 1.) Continue testing mixers and amplifiers. (Hopefully mixer #14 will be ready for testing. -It all depends on the success of finding another matched pair of amps.) 2.) Work on the mounting plate for the chopper wheel of the mixer test system. ******************************************************************** Report from Geoff Ediss Spent most of the week working on band6 PDR documents and presentations. Also reviewing band 9 PDR documents ready for the PDR next week. Completed an EDTN on solders at NRAO which should come out next week. ******************************************************************** Report from Alex Grichener A. PDR 1. Finished power point slides for the PDR B. Software Development/Support 1. Wrote a Band 6 software schedule 2. Wrote a rough draft of a software requirements document for the amplifier test system 3. Developed the user interface for the first build of the data acquisition program (Band6DAQ 1.0) C. Mixer Bias Supply 1. Held a design review 2. Spoke in person with Jeff Morris at WWW Electronics about putting the modified mixer bias circuit on a printed circuit board 3. Started porting the bias circuit schematic from AutoCAD to OrCAD ******************************************************************** Report from Neil Horner This week has been mostly report writing.. The IC was emptied and the floor waxed. The Tucson equipment came in today. We did some dicing and logging chip from SIS wafer #4 for use in mixers. Next week since the cartridge will be available I want to spend some time studying the whole structure. More mixer work as well. Name: Kamaljeet Saini IPT: Front End IPT - First Local Oscillator The following is a summary for the past couple of weeks to cover the hiatus in the weekly-summary submissions. (1.) Completed phase noise and phase drift measurements on the Band-6 AMC to study the impact of distribution of the LO reference signal as an intensity modulated signal and locking the LO driver at the YIG frequency rather than at the frequency of output of the LO driver assembly. The phase noise measurements were promising, but the phase drift would impose stringent requirements on the temperature control of the AMC and PLL modules in the LO driver assembly. A report containing all the details has been prepared and is available on ALMA EDM as document number FEND-40.10.00.00-020-A-REP. (2.) Completed debugging and testing the PLL modules (that were assembled by an outside vendor) required for integration into the LO driver assemblies due to be delivered later this month to the cartridge manufacturers and for the system integration tests. (3.) Phase noise measurements were completed on the first full-up Band-6 LO driver assembly in its final configuration as per the baseline plan, prior to its shipping to Tucson for the system integration tests. A report describing the measured performance is being prepared. (4.) Document describing the Band-6 LO driver hardware shipped to Tucson for the system integration tests was completed. It is available on ALMA EDM as document number FEND-40.10.00.00-021-A-MAN. This document is also intended to be a true description of the Band-6 LO driver assembly due to be delivered to the Band-6 cartridge manufacturers later this month. (5.) IRAM has integrated the first two production version Band-7 coolable frequency triplers that were delivered to them in early January into the prototype cartridges. These frequency triplers were intended to be used (in conjunction with the LO driver assemblies due to be delivered to them later this month) in the production version of the Band-7 front-end cartridge. Therefore they have indicated a need for additional two of these units. At this time I have no more units at hand, although we are expecting the vendor to deliver some within the next month or so. More units could be supplied only after after cryogenic and other testing has been completed on these new units. (6.) Dr. Gie Han Tan has conveyed that testing of the coolable frequency multipliers should include measurement of the level of unwanted harmonic content to ensure that specifications are met. This measurement has so far not been performed and was assumed to have been met by design. At this time, we are planning to perform tests to ensure compliance with regard to this specification. This will require design and machining of some waveguide blocks. This task will be initiated in the coming week. (7.) Developing the software algorithm to enable the LO driver PLL to automatically acquire lock and implementing it as a LabVIEW vi. So far LO lock acquisition was effected manually. This task should be completed in the following week. Name: Clint Janes IPT: Back End LabView tests of 2nd LO synthesizer have uncovered small spur, investigating. The LabView screen, which connects via TCP/IP, is really sweet and is an example of how remote diagnosis can be set up. 1st LO offset generators shipped to Tucson. Wiring up bins for Tucson tests. Prototype antenna racks that arrived damaged beyond repair last November were replaced this week, so now we can wire up the racks for prototype SI. Name: Jim Pisano IPT: Computing * Successfully enabled remote testing and operation of the ATF correlator software. Utilizing ACS and CORBA connections to the CCC and CDP at the AOC, we can send commands and receive spectral output using a Python GUI in Charlottesville. There still are some timing issues that require attention, but this functionality will be extremely useful throughout the correlator software development cycle. * Verified (via our remote connection) that software support for all 3 bandwidths (2 GHz, 250 MHz, 31.25 MHz) and 3 polarization sets (single, dual, full) are functioning correctly. * Enabled writing of final spectral (or lag) results to disk on the CDP. This allows for short dump durations needed for SI tests. * Enabled writing of intermediate data products for the CDP's spectral processing. This allows us to verify that each spectral processing step is correct by comparing the results with an independent set of calculations. This testing mechanism will be utilized from April - June. * Worked on porting our ATF code base to ACS 3.0. I have had some mild success, but I'm not there yet. * Continued working on design for correlator delays. Finalized quantized delay scheme for the correlator and the data structure published by the CALC model server and subscribed to by the correlator software (CCC and CDP). * Reviewed documents regarding the software algorithms for processing the data from the tunable filter. * Researching the PVM API to utilize it as a process control mechanism within the CDP. This should allow for process monitoring and restoration in case of software failures on the CDP compute nodes. * Wrote a brief design description of the correlator simulator. I will have a summer student this summer who will work on this project.