> Begin forwarded message:
> Hi Sandy,
> I think that a special session at URSI would be a very good idea — too bad 
> that we just set those for 2016 last week!  We can get it on the 2017 list of 
> topics — we are also looking to gather topics for the next URSI General 
> Assembly.
> In terms of communications, as you know we have spoken about a small workshop 
> and/or a consortium-esque, and Glenn had a good list of ideas.  I think a 
> good first step is to just collect a list of interested parties who might 
> contribute/profit by such a thing.  The model I guess that I have in mind is 
> something like the open-source CASPER community (which might have some 
> hardware appropriate for this — I’m thinking of the new SNAP board that we 
> are developing).
> I’m happy to set up and maintain the interaction infrastructure (e-mail list 
> and wordpress site), as we do a number of these things.  A start would just 
> be a description of systems (and of course links to material like the great 
> stuff Aaron and Carl sent).  Unless people object, I’ll set up an e-mail list 
> and seed it with this list.   Maybe for now we call it ratlab (Radio 
> Astronomy Teaching LAB), so the list would be ratlab@lists.berkeley 
> <mailto:ratlab@lists.berkeley>, and the website would be ratlab.berkeley.edu 
> <http://ratlab.berkeley.edu/>.  Do people think this is a good start to 
> keeping a dialogue going?
> At Berkeley, we are finishing up a 4.2m dish and will be putting on one of 
> the Caltech quad ridge horns for 1.15-6.9 GHz.  We have a couple of LNA 
> options (Miteq ~35K from 1-2.5 and ~65K from 1-4).  As Carl mentioned, we 
> have new drives and we are working on the software (pointing as well as data 
> collection).  We are also refurbishing the rooftop interferometer.
> Cheers,
> Dave
>> On Aug 18, 2015, at 4:41 PM, Sander Weinreb <swein...@caltech.edu 
>> <mailto:swein...@caltech.edu>> wrote:
>> Carl,
>> Thanks very much!  I looked at the attachments and the  four  experiments
>> including the write-ups  are  an excellent  introduction to  radio
>> astronomy.
>> A question about OH.  You mention <1K antenna temperature on the strongest?
>> maser source, W49.  Is  this  with the 4.5m telescope or with  an older,
>> smaller telescope?   I assume we would need narrow bandwidth, probably 5
>> kHz, and with  a 100K Tsys it will take many minutes of integration to see
>> the signal.   We  also have RFI around 1667 and it will be a challenge to
>> get the filtering and dynamic range.  On the other  hand, the polarization
>> and multiple lines,  make this  a very instructive venture.
>> I think we have had talks at URSI about educational radio telescopes but
>> maybe should devote a session  to this at the 2017 meeting.
>> Sandy
>> -----Original Message-----
>> From: Carl E. HEILES [mailto:hei...@berkeley.edu 
>> <mailto:hei...@berkeley.edu>] On Behalf Of heiles
>> Sent: Tuesday, August 18, 2015 4:08 PM
>> To: Sander Weinreb <swein...@caltech.edu <mailto:swein...@caltech.edu>>
>> Cc: heiles <hei...@astro.berkeley.edu <mailto:hei...@astro.berkeley.edu>>; 
>> <ddeb...@berkeley.edu <mailto:ddeb...@berkeley.edu>>; 'Alan Rogers' 
>> <arog...@haystack.mit.edu <mailto:arog...@haystack.mit.edu>>; 'Han'
>> <st...@kasi.re.kr <mailto:st...@kasi.re.kr>>; 'Steve Smith' 
>> <ste...@caltech.edu <mailto:ste...@caltech.edu>>; 'Monroe Ryan M'
>> <ryan.m.mon...@jpl.nasa.gov <mailto:ryan.m.mon...@jpl.nasa.gov>>; 'Gregg 
>> Hallinan' <g...@astro.caltech.edu <mailto:g...@astro.caltech.edu>>;
>> 'Andrew Janzen' <ajan...@caltech.edu <mailto:ajan...@caltech.edu>>; 'Ahmed 
>> Akgiray'
>> <ahmed.akgi...@ozyegin.edu.tr <mailto:ahmed.akgi...@ozyegin.edu.tr>>; 
>> asoli...@caltech.edu <mailto:asoli...@caltech.edu>; 'Hamdi Mani'
>> <hamdi.m...@gmail.com <mailto:hamdi.m...@gmail.com>>; 'Joe Bardin' 
>> <jcbar...@gmail.com <mailto:jcbar...@gmail.com>>; 'glenn.caltech'
>> <glenn.calt...@gmail.com <mailto:glenn.calt...@gmail.com>>; 'GLENN WEINREB' 
>> <gwein...@gwinst.com <mailto:gwein...@gwinst.com>>; 'Anthony
>> Readhead' <a...@astro.caltech.edu <mailto:a...@astro.caltech.edu>>; 'Shri 
>> Kulkarni' <s...@astro.caltech.edu <mailto:s...@astro.caltech.edu>>
>> Subject: Re: FW: Educational 6m Radio Telescope at Caltech
>> hi sandy...
>> in our undergrad radio astro lab, we currently do four major experiments,
>> the writeups for which are attached.
>> the first lab is devoted to bench experiments and learning about digital
>> sampling. the lab in in two halves, and in fact we treat it as two separate
>> labs. the first half uses test equipment; the second uses a horn on the
>> roof, baseband complex sampling with the students writing their own software
>> to get the power spectrum fromthe time series. i regard this first lab,
>> which covers the basics of sampling and Fourier tranforms, as absolutely
>> crucial for anybody who intends to pursue a technical career, and also
>> everything that follows in the lab course.
>> the second lab uses our 12 GHz interferometer (freq chosen so that we can
>> look at the strong methonal masers--which we haven't gotten to yet).
>> baseline is about 12 m. students do vlbi fringe fitting to determine
>> accurate declinations of sources like Ori A (well, more accurately, the
>> combination (baseline times cos delta). also look at fringe amplitude
>> modulation to determine angular diameters of the sun and the moon.
>> the third lab uses our 4.5m dish located about a half hour away to map HI
>> 21-cm line, look at OH, and look at pulsars. Haven't done OH successfully
>> yet because of equipment problems, but hope to do so this coming year, and
>> include polarization. hope to get to pulsars this coming year, but that
>> requires some programming for our FPGA spectrometer and might not happen
>> this year.
>> generally, course philosophy is that students must write their own software.
>> we use IDL. these days, Python would be more approppriate, but at my age I'm
>> not going to learn yet another language. anyway, the programming experience
>> gained helps the students a lot in REU research programs and getting a
>> flavor of instrumentation for later career use.
>> if you desire, you can find some more info (handouts, writeups, etc) on my
>> web page astro.berkeley.edu/~heiles/ <http://astro.berkeley.edu/~heiles/>
>> it strikes me that if you can't do OH simply because of resolution of your
>> spectrometer, then this is an excellent project for them to do direct
>> voltage sampling on and they could do their own FT power spectra with
>> arbitrary resolution. this would be very instructive. 
>> bandwidths can be small so you can keep up with the data rate and disk files
>> don't need to get too big. many OH masers are highly polaarized, so a good
>> excuse for them to learn polarization basics. W49 is a particulary good
>> example. Also there are very strong OH masers associated with IR stars, also
>> polarized.
>> our telescopes are pointed now by commercial motor controllers, thanks to
>> dave deboer. doing this well (or even at all) is difficult. i suspect alan
>> has a simpler and cheaper alernative. also, our telescopes are home grown;
>> the hardest part is the pointing hardware and software...
>> good luck and have fun! there are some other similar labs...i know UW at
>> madison has one. we ought to convene a get-together so we can exchange
>> ideas...
>> --c
>> On Sun, 16 Aug 2015, Sander Weinreb wrote:
>>> (Corrected email address for Heiles)
>>> From: Sander Weinreb [mailto:swein...@caltech.edu 
>>> <mailto:swein...@caltech.edu>]
>>> Sent: Sunday, August 16, 2015 10:31 PM
>>> To: carl heiles (hei...@vermi.berkeley.edu 
>>> <mailto:hei...@vermi.berkeley.edu>) 
>>> <hei...@vermi.berkeley.edu <mailto:hei...@vermi.berkeley.edu>>; Alan Rogers 
>>> (arog...@haystack.mit.edu <mailto:arog...@haystack.mit.edu>) 
>>> <arog...@haystack.mit.edu <mailto:arog...@haystack.mit.edu>>
>>> Cc: Dave Deboer (ddeb...@berkeley.edu <mailto:ddeb...@berkeley.edu>) 
>>> <ddeb...@berkeley.edu <mailto:ddeb...@berkeley.edu>>; 'Han'
>>> <st...@kasi.re.kr <mailto:st...@kasi.re.kr>>; Steve Smith 
>>> (ste...@caltech.edu <mailto:ste...@caltech.edu>) 
>>> <ste...@caltech.edu <mailto:ste...@caltech.edu>>; Monroe, Ryan M (382F) 
>>> <ryan.m.mon...@jpl.nasa.gov <mailto:ryan.m.mon...@jpl.nasa.gov>>
>>> Subject: Educational 6m Radio Telescope at Caltech
>>> Carl and Alan,
>>> I need some advice from old salts about how to demonstrate radio 
>>> astronomy observing techniques to new graduate students.
>>> We are paying some attention to the  6m  telescope on the roof of the 
>>> EE building at  Caltech  and are trying to make it into  a good 
>>> teaching instrument.  The front-end covers 1.3 to 1.7 GHz with about 
>>> 100K Tsys on two linear  polarizations and we recently installed a 
>>> Roach 1 spectrometer with two 500 MHz bandwidth channels  and 60 kHz 
>>> resolution. There is much RFI and a lesson we want to teach is how to work
>> around it.
>>> Our weakest link is the software to integrate telescope pointing with 
>>> receiver output.  We are working on developing a convenient system   
>>> but I wonder if it already exists on other  small telescopes.  Do you 
>>> have any suggestions for integrated telescope and  data taking  
>>> control system we should look  at?
>>> A second  topic  is  what to observe with the  telescope as 
>>> educational demonstrations.    We can certainly map galactic hydrogen 
>>> and  look at  the stronger continuum sources.  The spectrometer can 
>>> cross correlate the two linear polarizations and we could get into 
>>> polarization measurements. Do you have suggestion  for observations?
>>> I would like to observe OH  (again, since I have not observed it or 
>>> followed what has  been done since 1963 !).   Where is a good summary 
>>> of the observations?   I think  our 60 KHz resolution is too  broad 
>>> and we will need to improve it by a factor of 10 or more.
>>> Sandy

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