Archive for April, 2011

21
Apr

slow spring

   Posted by: kevin    in gardening

The temperatures have been cool… very cool… so cool that a lot of our plants are behind already and getting farther back. Temperatures remain well below average and the little heater in the uninsulated greenhouse is going full tilt most of the time. Peas went into the ground last weekend as did some beets, but nothing has shown yet. We did get 41mm of rain last weekend in one day alone and 25mm more yesterday. At least the ground is not frozen anymore and letting a lot of it sink in.

We get a break tomorrow with a double digit day and some sun… but then several more days of cloud and rain.
Bummer.

18
Apr

Radio Jove receiver assembly

   Posted by: kevin    in astronomy


We did it. After 2? 3? years of having other things happening in life get in the way, we assembled the Radio Jove RJ1.1 Receiver Kit, a 20.1MHz radio receiver. It took us about 4 hours to wire and solder together and then about 2 hours to put it into the enclosure and test it. There were over 100 components to solder in and now I can see why the price tag for an assembled receiver is so much more than the kit!

Some of the harder parts of assembly were the identification of some of the smaller parts, with very tiny markings on them, like the picofarad capacitors, the inductors and some of the germanium diodes.

.

Luckily they started us off easy, with the soldering of 10 jumper wires first. Followed by the resistors and later on moving into the semiconductors. After a few hours and dozens of connections, Kim was soldering like a pro. When the last solder connection was done, we both inspected the board and touched up any joint that looked suspect.

A short lunch break followed by the assembly of the enclosure. Actually that was supposed to be first but we missed that instruction :)

The calibration sequence consisted of finding the 20.0 MHz oscillator signal in the powered speakers by adjusting a variable inductor L5 I believe it was, after a ten minute warmup. We noticed during that warmup, some variance in the tone. After that we, in sequence, adjusted another variable inductor (with a plastic tool to avoid interference), and two variable capacitors. Within a short time we had the strongest signal and powered everything off, cut the jumper wire that supplied power to the test oscillator and reassembled the enclosure.

The last step is to install all of this out in the observatory, cut an RG-6 coax cable to a 1/2 wavelength increment to reach out to the antenna connection, fire it up and wait for Jupiter!
Hmm.. too bad Jupiter is in conjunction with the Sun. Oh well, we can also put up another dipole antenna and study the Sun!

We tried to think back a couple of summers ago when we were watching Mark assemble the North York Astronomical Association radio jove receiver.
All in all it went very well and the next step will be installing it in the observatory and connecting it to the antenna we put up last summer.

Some notes from the assembly manual:
Radio signals from Jupiter are very weak – they produce less than a millionth of a volt (1 microvolt, 1v) at the antenna terminals of the receiver. These weak radio frequency (RF) signals must be amplified by the receiver and converted to audio signals of sufficient strength to drive headphones or a loudspeaker. The receiver also serves as a narrow filter, tuned to a specific frequency to hear Jupiter while at the same time blocking out strong earth based radio stations on other frequencies. The receiver and its accompanying antenna are designed to operate over a narrow range of short-wave frequencies centered on 20.1 MHz (megahertz). This frequency range is optimum for hearing Jupiter signals.

18
Apr

New Dew Heaters

   Posted by: kevin    in astronomy

Back last fall I was fortunate enough to win a $50 gift certificate from Kendrick Astro Instruments in Toronto at the Fall’N'Stars Star Party 2010. I had won one in the past but lost it and forgot to use it/could not find it before it expired.
This time however I ordered almost immediately. I was looking for a spare heater controller as of the two we have, one is a little flaky. I was also looking for a heating band big enough to use on our cameras and or big 2″ eyepieces.
Well, the order arrived late last week. I was not lucky in that the controller I had ordered was discontinued and the new design was not in production yet.
Here is the new Firelite micro controller (with two standard size RCA jacks), and the Dewminator (2006-L DEW-Minator Large Eyepiece Heater 10 0.8 75 x 205 mm 3″ x 8″)

Using the micro controller is going to be harder than I thought. It has a single control button, used in various ways, (push, push and hold), sequences (wait until one state occurs than push for more commands), etc. It was a way to reduce the cost of a controller down from $120 to $76 but we will wait and see for a final judgement once we use it out in the field.

The specs say it can handle up to 12vdc, 7 amps = 84 watts, which is a *lot*.
The 2006-L Dewminator Large heater is designed for 10 watts.

15
Apr

Food Bank powerpoint

   Posted by: kevin    in Uncategorized

A short presentation about the local Kingston Food Bank:

http://starlightcascade.ca/mission_in_partners_food_bank-kingstons_helpful.ppt

13
Apr

Tech talk for wednesday

   Posted by: kevin    in astronomy, tech

The day or two after? the allsky camera system captured a great big fireball in the sky it failed to show any images tuesday morning. We use VNC to remote desktop in and see that the CCDOPs software declared an unknown “operating system error” and hung. Restarting the laptop running windows XP (up for 30 days previous to this), fixed everything. As of this morning, all was automated again.

Last Earth Hour one of the desktop computers was powered off to conserve energy for the event. Only it did not want to turn back on again. After swapping out various pieces: memory, power supply, unplugging accessories, etc, we figured out that it was the old motherboard, salvaged from a flood back in 2008.
So out came the two hdd IDE drives, the two IDE DVDRW drives, the memory, NIC, video cards.
The power supply was old so it and the case went to ewaste recycling.

I cobbled together a new system based on a lot of other spare parts including a biostar 945GZ motherboard.
Only the problem with it was it had only two IDE connections, not four as before. What follows is a workaround to get a system up and running again.
Since we wanted two dvdrw drives and all we had were the two IDE ones, we needed a hard drive with SATA connections, which we had a spare.

*install old 80gb ide boot drive and new 500gb sata drive and one dvdrw ide drive.
*boot into linux fedora 14 live cdrom
*open a terminal, run the command “dmesg | grep -i sd” to identify which drive was which. sda was the 80gb and sdb was the 500gb.
*run the command “dd if=/dev/sda of=/dev/sdb” and about an hour later an identical clone of the 80gb drive had been copied onto the 500 gb drive.
* remove the 80gb drive and attempt to boot into the 500gb sata drive. it booted ok but windows failed on startup. Trying safe mode and other combinations all failed. Ug.
* boot into windows xpsp3 cdrom and choose 2nd repair option and basically reinstall the operating system without overwriting or reformatting the drive. 30 minutes later it boots ok.
* it is missing a lot of drivers so off to search google for “biostar 945gz 775se drivers”, find them, download them and install them. Restart.
* connect to the net, and do a windows update. 90 odd updates later, shutdown.
* install the 250gb IDE drive and restart
* create a new 300gb partition in the 500gb sata drive, format it as NTFS and start to copy all of the
data off the 250gb drive. An hour later shutdown and remove 250gb ide drive. Connect 2nd ide dvdrw drive and restart
* desktop computer is mostly where it was before the failure. All of the programs are there, installed, registered and operational.
* store the 80gb and 250gb ide drives for future use.
* fireup boinc with seti@home and run at 100% for the day to stress test the system.

The plan is to use the remaining 90gb or so at the end of the 500gb sata drive to install a dual-booting fedora linux 14 system.

The new system should use less power as it has only a single newer sata drive as opposed to two older IDE drives plus a more modern processor that should not run as hot.

10
Apr

Allsky event 2011-04-10 00:48

   Posted by: kevin    in astronomy

Was anyone observing outside after midnight early Sunday morning?
The reason I ask is that our allsky camera caught an anomaly, that if it were a meteor, was spectacular.
Below are three images, before, during and after the anomaly.


It does appear close to our chimney and we did have a fire going last night that normally produces a much smaller smoke plume than this. Perhaps it was lit up by passing car headlights.

The image itself is a 120 second exposure ending at 00:48:21 on 2011-april-10
Offhand it looks like it has the characteristics of a fireball moving east to west, starting small and growing larger over time.

One of the problems with this time lapse integration method is that you never know if you actually got the start or end of the event. Sometime in the future we will move to a better low light camera system with GPS time annotations like these
http://science.nasa.gov/science-news/science-at-nasa/2011/31mar_springfireballs/

updated:
There have been many other eyewitness reports of the fireball event early this morning
from
http://lunarmeteoritehunters.blogspot.com/2011/04/ontario-green-fireball-130-am.html