Friday, November 27, 2009

Google Groups "Cellphonia" jacked?

Forgive the kvetch. I believe that Google Groups "Cellphonia" group has been jacked and I can not remember if I created the group or not. I don't seem to be the owner. Any thoughts how to fix this problem before we call in an n-strike.

Tuesday, November 24, 2009

Seasonal Gift List 2009

Latest items (not on Amazon list :)


Digital Oscilloscope DIY Kit from SparkFun. This kit includes everything you need to build your very own, fully functional, digital oscilloscope. Once you've got it up and running, the oscilloscope features up to 5M samples/second, 8-bit resolution, up to 50Vpp max input voltage, and more! And BNC Probe Kit is a necessary signal snatcher to go with scope.


Bluetooth® Portable Rotary Phone - Black or another color from SparkFun. Links nicely to your cellphone, lessens EMF on those incoming/outgoing calls.

SolderPro 50 Butane Soldering Iron Kit

Illuminated LED Eye Loupe



Amazon wish list: http://amzn.com/w/1IMTKAY992X5M.

Book (before I discovered Amazon service):
The Book of Codes: Understanding the World of Hidden Messages (Hardcover) - Paul Lunde (Editor)

Saturday, November 14, 2009

Power Supply for Benjolin and Zeitgeist

I just received a 25W AC - DC Triple Output desktop power supply made by MEAN WELL, Model: P25A13D-R1B. Data sheet at https://www.jameco.com/Jameco/Products/ProdDS/190960.pdf. I intend to power both my Benjolin and Zeitgeist from this AC-DC supply. I also ordered the 5 pin female DIN connector from Jameco-- take a look at either Jameco part number 15844 or 29399. They were cheap enough that I ordered one of each to have a choice for the final install. At of this writing Jameco has more of these power supplies in stock and Jameco prices are the lowest, and shipping w/in USA is good.

Below I cut-n-paste as email (Nov 8, 2009) from Rob to myself and others with good advice on power supplies:

Hi all,

My recommendations for a power supply for both the Benjolin and the
Zeitgeist.

Principally I do always recommend a desktop Plug-In AC Adapter power supply similar in looks to the ones used for laptops. These are the safest devices to use in terms of hazard of electrical shock. Regrettably they are a bit hard to find. But note that if you want to do circuit bending experiments, especially when they involve body contacts, then *always* use batteries!

A good choice for a desktop power supply is one that is sold by Mouser.com:
http://www2.mouser.com/ProductDetail/Mean-Well/P50A13D-R1B/?qs=sGAEpiMZZMtpk
qKkT5w3uiB%2fqpDJDtRebgXKIecL%2f1U%3d

(Regrettably it seems to be a non-stocked item and might have a delivery
time of perhaps up to ten weeks.)

A simple 5-pole female DIN connector can be used on the enclosure of a project to connect to this power supply. By using two female connectors on the back of every enclosure one can daisy chain the power to perhaps five to ten more boxes. Desktop power supplies are the easiest to share amongst several projects, which is a definitive additional value.

When putting a power supply into the housing of a specific project I would recommend a closed frame power supply like:
http://www2.mouser.com/ProductDetail/Mean-Well/T-40B/?qs=sGAEpiMZZMu0oxGuRuN
KHzvx70GkCU%252bvmzt/DvjUqMo=

This is also a very good alternative to a desktop supply when putting this supply into its own plastic housing with several connectors to power several projects at once, thus turning it into a desktop power supply all by itself. Probably this power supply is the easiest available one, and so you might consider it if you do not succeed to find a suitable desktop power supply.

In essence it would be possible to use a frameless power supply like:
http://www2.mouser.com/ProductDetail/Mean-Well/PD-2512/?qs=sGAEpiMZZMu0oxGuR
uNKHzvx70GkCU%252bv%252bAeyeoSWfsA%3d

but I do *not* recommend an open frame power supply for ány DIY project, simply as the maybe twenty bucks extra that you pay for a closed frame supply or thirtyfive bucks extra for a desktop power supply are peanuts when at a moment in the future it does actually protect you from electrical shockand saves your life! Never take any risk with AC power!!!

Regards,
/Rob