Catwalker

Well, the project I started previously:

Micro controller Programmer

Is basically complete and functional, just needing expansion boards now. The big hold up was gaining access to a functional programmer in order to program it (ironic - needing a programmer to make a programmer work :))

Later this week I will make photos of the next bevy of projects, all to do with music.

じゃまた

Well, my last post was a while ago (what else is new? :) ) So I have been doing some electronics and in the next week or so will post some shots of the boards and semi - completed projects. (All of the projects I am working on right now will combine into one big project, so a bunch of sub assemblies need to be completed before I can show off the final project)

Stay tuned.

I am well known for being a despiser of all things Microsoft and Apple, therefore I need an alternative. My chosen alternative is Linux. At the moment I use the Ubuntu release. It works well and is fairly easy to manage. As a part of this I use OpenOffice, which works really well. B*U*T there are some things which are seriously in need of fixing:

• Word count is broken
• Select, cut and paste is flaky

What do I mean by word count is broken? It counts all words in a document, even the footnotes. When you do a university paper most profs won't let you include the footnotes in the number of words your document contains. Footnotes can add 1000 or more words to a document. And select and count doesn't work properly either. If I want a more-or-less accurate word count, I still have to use M$ Word to do it. Now cut and paste is flaky in that when using the mouse you select a block of text, the right click to select often the block you just selected will de-select itself, then you have to re-select it. This is no big deal, if you just remember to use the keyboard shortcut ctl-c/x depending on whether you want to copy or cut. If the good folks working on OO would fix these two hiccups I would be very happy indeed.

Well, it was time for a brief respite from summer heat and soldering bits together, so we went to a fireworks display nearby, it was a nice show, if somewhat short. (I gather a display like this can be somewhat pricey)








The display lasted about ten minutes, lots of the usual flash and bang.



(Yes, these are my photos)

 

 

 

じゃまた

A .036 carbide drill bit in my O*L*D Dremel 370 Moto Tool, I have had this old beast since about 1975 it was a Christmas present from mom and dad. It is still running strong, but doesn't even appear in the "discontinued tools" section of the Dremel web site (neither does the matching drill press stand, for that matter.) This is the smallest drill bit I have ever used.




The drilled and marked board (I decided to see if the toner transfer method would work just as well in putting the parts layout on the board, it did, more - or - less)




The board, just needs a couple of parts I forgot to order (oops)




A note - the tiny little drill bits are F*R*A*G*I*L*E I broke mine (thankfully, I was finished drilling) when I was going to take it out of the moto - tool, I dropped the tool, drill bit and all and it snapped it off....

じゃまた

Time for yet another new project, today I'm just posting part one. Part two will come later. Today I'll give some brief details about the printing of the PCB. Or "Printed Circuit Board". The project I am making isn't my own this time, but can be found here: Open Programmer It is a programmer for microcontrollers. Mainly, the Microchip PIC series.


Here are the raw materials for making the PCB, invisible is a piece of plywood (more on that a bit later) and no, the inclusion of a clothes iron is no accident. The newest tool in my staple of electronics bits and bobs. Why an iron?






Because for the first time,
I am using the
TONER.... TRANSFER.... METHOD....
as Bre Pettis from Makezine puts it.
The last time I made a PCB, it was about 17 years ago, I had no access to:

a) UV exposure boxes
b) Sensitised boards
c) developer
d) money for all of the above :)

I used to cover the copper clad board in wide strips of masking tape, draw on the pattern, cut it out with a sharp Xacto knife, paint the exposed copper with acrylic paint, let it dry, peel the tape away, patch up any damaged areas, etch the board. This worked, but it was overly time consuming, messy and couldn't really do fine traces. And the etch resist pens from Radio Shack were crap.

Check out this like: Make your own PCB's for the full explanation, the Youtube video references this site: Toner transfer method as explained by Thomas Gootee. Be very careful when using the etchant mix, I'm told it can become exothermic under the right (or should I say wrong?) circumstances, and it it needs to be used O*U*T*S*I*D*E or in a well ventilated space - it's toxic and it stinks. And if you get it on your mom's (or your wife's) stainless steel sink, you could be sleeping in the dog house. (You may be better off using ferric chloride - I was impatient so made my own etchant).

(BTW - If I were you, I wouldn't take Zander up his suggestion about amusing Law enforcement - There seems to be somewhat of a lack of a sense of humour on the part of a number of law enforcement officials --- some will be amused, others ... not so much -> just sayin :) )


I had a smallish piece of plywood, which I placed under the copper clad board, so I would n't damage anything underneateh. Here is my piece of plywood after ironing the paper pattern onto the copper clad board. It got pretty hot.







The board was hot enough to sizzle when I slid it into the bowl of hot water. As you can see, the paper is actually slightly scorched.





After about ten minutes of soaking in the hot water, I was able to carefully peel away part of the first layer of paper on the back, you can see the pattern from the paper plainly stuck to the copper clad board.





Here is the board with the paper gone ( a little bit of residue to clean up) I was surprised at the results, especially considering some of the traces are very small.




Board etched - I have deliberitely darkened the image a bit so you can see that the excess copper is gone, and the board is trimmed to size (about 2 3/4 x 4 inches) - just a couple of more things to do...



Board mostly complete, with the toner scrubbed off with acetone (use a mask, and ventilation - acetone is nasty stuff) - those couple of things to do? Clean it a bit (there are a couple of traces shorted together) and drill the holes - for that I need to get a couple of Carbide drill bits, FR4 glass epoxy and copper make quick lunches of HSS drill bits and band saw blades.


Coming up, once drilled, I will show off the completed project, and the reason I am going to all this effort.

じゃまた

It is now the 4th of July, to my American friends, take pride in this day. Your founding fathers risked quite a bit to start your republic.  233 years, it seems like a long time to us, but the U.S.A. is still young. Here's to 233 more.

Freedom Is Not Free To my American friends on memorial day, thanks. And to those who never made it back, thanks just does not cut it.

On the left is the audio amp board, on the right are the two audio amp IC's (did I mention I H*A*T*E desoldering and resoldering Integrated Circuits? Thankfully these have only ten pins :-) ) The chip on the extreme right is the good one the one to its left is the dead one.
Two electrolytics, the one on the left with the disc ceramic cap and resistor is one being replaced (there are two assemblies like this to be replaced) Notice how much shorter the new one is?
 The new one now with a disc ceramic cap and a resistor added.
The rig purring away nicely. Still some stuff to do, but it is now functional and at least I can listen in. The pile of parts in front are the bits I have replaced so far. 

 

 

 

 

 

 

 

 

 

 

じゃね