Wednesday, May 5, 2010

Excel: Reformatting timestamps to get a graph with time on the x axis

Time column is in decimal seconds from some completely random timebase, which I took one calibration of.

Created a column with format "Time" of type hh:mm:ss. Formula for that column was:

=TIMEVALUE(TEXT("8:21:00 AM"+(A2 - 906897)/86400, "h:mm:ss"))

i.e. A2 contains a time in seconds, at 8:21 AM the seconds were 906897, and the conversion factor is expecting decimal hours (86400 seconds per hour). Converting it with TIMEVALUE produces fraction of a day, but that is then displayed properly due to the cell formatting.

This does not address the case of crossing a date boundary. Date conversion functions are not useful because the only cell formats available for date do not include seconds.

Monday, May 3, 2010

Master Cam 9

Another search:

http://www.google.com/search?hl=en&q=autocad+to+mastercam+translator&aq=f&aqi=&aql=&oq=&gs_rfai=

Industry Links

News Feeds:

Nucleus, at hobbyspace.com, the best newspace source now that spacefellowship.com is all crapped up with NASA press releases.
http://www.hobbyspace.com/nucleus/index.php

Jeff Foust's information packed spacepolitics blog:
http://www.spacepolitics.com/

The Once and Future Moon blog:
http://blogs.airspacemag.com/moon/

Live Media:

Spacevidcast, spotty but still the most extensive coverage of newspace events:
http://www.spacevidcast.com/

Some kind of KSC voice loop available through internet radio as of 6/2010:
http://www.radioreference.com/apps/audio/?action=wp&feedId=705

Newspace projects' individual sites:

Unreasonable Rocket:
http://unreasonablerocket.blogspot.com

JP Aerospace (those crazy balloon guys):
http://jpaerospace.com/blog

Master Cam 9

Why Can't Tony Read? Found info on Master Cam 9.

The manual, "What's new in Master Cam 9":
http://www.scribd.com/doc/12359930/Master-Cam-9

Google search with results including, ironically, cracked copies on bittorrent.
http://www.google.com/search?hl=en&ei=icvVS-f3GJf0NLWd3NID&sa=X&oi=spell&resnum=1&ct=result&q=Mastercam+version+9+autocad+translation&spell=1

Sunday, April 11, 2010

Mil spec electrolytic capacitors

Trying to figure out how to specify the caps that are in the parts drawer. They are clearly mil spec. MFR on the cases are Kemet, sometimes Sprague. Other numbers from the cases don't match any searches. One has a milspec part number M390006 on it.

What I have learned is:

Vishay does sell the M390006 ones:
http://www.vishay.com/docs/40022/40022.pdf

Sprague is now a subsidiary of Vishay. They sell caps very similar looking to the mil spec ones as series 150D which are "Hermetically Sealed" Tantalums. The datasheet says "The Military equivalent to the 150D is the CSR13 which is qualified to MIL-C-39003/01" The 150 series is available plentifully.

http://www.vishay.com/docs/40015/150d.pdf

CSR13 doesn't come up on many searches, and is apparently obsolete. However, I did find a Kemet datasheet which explains the numbering very clearly

http://www.kemet.com/kemet/web/homepage/kechome.nsf/file/Tantalum%20Hermetically%20Sealed-Axial%20Catalog/$file/F3100_TaHermSeal.pdf

Furthermore, after the first page of the above, there is an explanation of Kemet's newer numbering system, which is byzantine but the parts are available plentifully.

The difference between the M390003 and the M390006 is that the former is a solid tantalum, the latter a wet tantalum, as explained on the below surpluser's page. It appears that I have a bunch of the solid ones.

http://www.smcelectronics.com/milcap.htm

Monday, April 5, 2010

ERROR (LM-20): user/host/display not on option INCLUDE list for feature "Capture" ().

Trying to debug what happened to my OrCAD license yet again.

Google searching on the above error message, directed me to this page which does a damn fine job describing the INCLUDE list and other options file parameters:

http://www.ansys.com/products/icemcfd-tech-notes/flexuser/chap5.htm

Further digging shows that this file is just my license.dat file under C:\flexlm

Naturally, there is no "Capture" feature listed because our OrCAD is a site license. There's a bunch of Actel software features listed though, and I bet that when I installed those I somehow messed up the pointer to the OrCAD license server

Thursday, April 1, 2010

iphone keyboard

Here is my first google search:

http://www.google.com/search?hl=en&source=hp&q=keyboard+for+iphone+bluetooth&aq=f&aqi=&aql=&oq=&gs_rfai=

The keyboard described in this breathless article seems not to have arrived, but one can always hope for the future.

http://www.appletell.com/apple/comment/a-bluetooth-keyboard-for-the-iphone/

The bottom line is that you have to "jailbreak" the phone to install a keyboard app, Apple will not allow installation of the bluetooth layers for keyboard interfacing. Here is a google search on the most popular hack:

http://www.google.com/search?hl=en&q=keyboard+for+iphone+bluetooth+BTStack&aq=f&aqi=&aql=&oq=&gs_rfai=

Here is a painstaking tutorial on how to download and install the hack:

http://www.iphonehacks.com/2010/01/how-to-use-a-bluetooth-keyboard-with-your-iphone.html