PCB layout, Filters, SEQ uP

[Roman Sowa]

Hi all,
recently I've seen too much posts from me on the list, so here is
a compilation of my comments

First of, thank you all for nice words about my website
www.multimania.com/romcio
Now I'm more convinced that I'm doing it the right way.

PSBs - wirewrap:
Maybe I'll put a photo of my first VCO prototype on the web.
Then you'll see what wirewrap means to me - no board and works!

according to Jorgen's post:
> 1. Most software cost money. A general drawing program is useful for so
many
> other things, that you want to have it in any case.
True, they cost money, but when I played with evaluation version of Corel
Draw
I uninstaled it after two hours. Much worse for me to use than any PCB
software.

> 2. When I design the board manually, I can do sneaky things like shaving
off
> portions of pads to make room for a trace that would not otherwise fit.
The boards I
> have seen other people do are not as compact and have more wire links than
mine,
> that's a fact.
That's becouse you haven't seen mine ;-). But seriously, you can always
define other than circle pad type.

> 3. I can design the schematics symbols to look exactly like I want them. I
have
> emulated the style in Elektor magazine, for nostalgic reasons.
PCB software can do that

> 4. I can have beautiful full color parts placement diagrams. My parts
symbols look
> almost exactly like the real parts.
You make PCB or painting for art gallery?

> 5. It is good brain gymnastics to keep the routing in the head.
Occasionally I make
> a mistake, but it is necessary to build a prototype anyway. Board layout
errors are
> usually easy to correct on the prototype.
Yes, I sometimes get up from designing PCB completely exhausted. And they
always contain mistakes anyway. But with PCB software you can draw
the schematic and it will check if it matches PCB you've drawn.

Filters:
I made some time back a Windoze software which turns your mouse
drawn FIR frequency response into coefficients.
And btw uploads them to my DSP board or writes to file.
Anyone interested? Should I bother making english version? Free!

Tuning FIR filters:
Make large FIR, and sample its coeffs like you do with wavetable.
Then you get low freq filter with narrow spaced samples
and high freq filter with wide spaced coefficient samples.
Somehow I feel this description wasn't clear...

Sequencer microprocessors:
It might be overkill, but when PIC16F84 is running out of resources
I like to put 80C188 in action. Then I'm limited only but imagination.
Although it requires some extra ICs.
btw there is new PIC coming out soon. It's flash version of 16C7x
or something like that. At last!
And Hitachi makes nice uPs. 128kB of flash, free C, about 20$
don't remember part name tho...

Roman