Re: ATM Mel's Dob stepper circuit

["arthur" <gw8fkb@telinco.co.uk>]

Hi Dawie,


>
>I have a few questions about the circuit :
>
>1) The Zener Diodes : Is the 5W really neccesary, because al I can find is
>2.5's. Can I maybe use two 2.5's instead of 1 5W ?
>
No unfortunatly, the zener diodes have a tolerance & the chances of finding
two with the same zener voltage is remote. The one with the lowest
zrnervoltage  will therefore conduct while the othere one floats until the
first blows! the second does the same then.

>2) On the 7802, there's no numbers or anything indicating where to put
what, all
>it has is a left, middle and right pins. When you turn it around it
switches. So
>where does what come ??
>
I'm not sure if that 7202 is correct? if its a voltage stabelizer?? looking
at thefront pins down the input [high voltage goes into the left middle pin
is ground & right pin is the stab voltage out.
>3) On die 74LS04's I know where the numbering starts, but where do they go
?
>Anything like this :
>
>1  2  3   4   5   6   7
>8  9 10 11 12 13 14
>
>or
>
>1  3  5  7  9  11  13
>2  4  6  8 10 12  14
>

the plastic pack has a n indentation in the middle of one of the shorter
sides [on top]
pin  1  ONE is  top left pin and pins numbered anticlockwise all around the
chip.


                14  13  12  11  10  9  8


                > indent
                 *  Or mark here.
                 1    2    3     4    5    6   7
>4) Any other software that would use the same circuit ?
>
Sorry not my field but will be interested in other views

>5) Anybody offended by this stupid questions ??
>
I hope not, why should they be??
arthur. gw8fkb/