http://c64mags.untergrund.net/wiki/index.php?action=history&feed=atom&title=The_Link_09_ElectronicsThe Link 09 Electronics - Revision history2026-05-03T18:07:16ZRevision history for this page on the wikiMediaWiki 1.19.0http://c64mags.untergrund.net/wiki/index.php?title=The_Link_09_Electronics&diff=6282&oldid=prevJazzcat: Created page with "<pre> electronics £££££££££££££ by GURU/TSR in this montly chapter, i will be giving you ideas and theory for useful electronic circuits. ..."2013-01-09T10:16:27Z<p>Created page with "<pre> electronics £££££££££££££ by GURU/TSR in this montly chapter, i will be giving you ideas and theory for useful electronic circuits. ..."</p>
<p><b>New page</b></p><div><pre> electronics<br />
£££££££££££££<br />
<br />
<br />
by GURU/TSR<br />
<br />
<br />
<br />
<br />
<br />
<br />
<br />
<br />
<br />
<br />
<br />
in this montly chapter, i will<br />
be giving you ideas and theory for<br />
useful electronic circuits.<br />
<br />
for those of you who don't know<br />
a capactior from a potentiometer from a<br />
pile of shit, return to the menu as this<br />
is NOT your chapter<br />
<br />
<br />
<br />
this month i will show you how to make<br />
a simple crossover network for speakers<br />
<br />
a crossover network is a circuit that<br />
acts as a filter. it filters out HIGHER<br />
frequency signals from LOWER frequnecy<br />
signals and send them off to the correct<br />
speaker ie. high freq. to tweeters, low<br />
freq. to woofers.<br />
<br />
crossovers are used so as to<br />
increase to performance of speakers,<br />
especially at higher volumes.<br />
<br />
only two types of components are<br />
needed for most crossovers, capacitors<br />
and coils.<br />
<br />
a capacitor in series with a tweeter<br />
will filter out low freq. signals<br />
<br />
a coil in series with a woofer will<br />
filter out high freq. signals<br />
<br />
non-polarised, non-electrolytic<br />
capacitors are recomended for this type<br />
of work so greencaps, paper caps, or<br />
even bi-polar electros are usable.<br />
<br />
<br />
coils.... thats another story, i have<br />
searched the catalogues of many major<br />
electronics distributors and have only<br />
found one that sells coils - JAYCAR<br />
ELECTRONICS - , although they are rather<br />
expensive at around $5.50 each.<br />
<br />
if you prefer, you can get old<br />
power transformers, and experiment with<br />
using the secondary winding as straight<br />
out coils (thats all they are after all)<br />
<br />
<br />
or, you can wind your own.<br />
<br />
about 210 turns on an air cored wooded<br />
rod (16mm long, 12mm diam.) will give an<br />
inductance of 0.5 MILLIhenrys<br />
<br />
as above but with 300 turns will give<br />
you about 1.0 MILLIhenrys<br />
<br />
you can also use this formula to work<br />
out sizes etc.:<br />
<br />
2 2<br />
l=0.2a n /(3a+9b+10c)<br />
<br />
where:<br />
<br />
l=inductance in MICROhenries<br />
a=average diameter of coil in inches<br />
b=length of the coil in inches<br />
c=radial depth of the winding in inches<br />
n= total turns of wire<br />
<br />
OFF THE SUBJECT OF COILS<br />
<br />
<br />
the basic circuit diagram of a crossover<br />
<br />
<br />
##<br />
""""""[][][]"";""""##"""""""<br />
# coil ! ## #tweeter<br />
!+ # ! cap. # +!<br />
! #""# input #""# !<br />
! # # # # !<br />
! # # ! # # !<br />
! #""# ! #""# !<br />
!+ """""""""""""";""""""""""""" +!<br />
woofer<br />
<br />
<br />
<br />
the following table will show you<br />
what coil and cap. to use for certain<br />
cut-off frequencies (depending on<br />
the characteristics of your speakers)<br />
<br />
<br />
for 8 ohm<br />
<br />
<br />
hz coil(mh) hz cap(uf)<br />
<br />
250 4.0 2000 10.0<br />
500 2.0 3000 6.8<br />
750 1.47 4000 4.7<br />
1000 1.0 5000 4.4<br />
2000 0.47<br />
<br />
<br />
if you are using a 4 ohm system,<br />
half the coil's value and double the<br />
cap's value.<br />
<br />
<br />
<br />
<br />
<br />
if you need more information<br />
(proper diagrams), on<br />
this or any other topics<br />
<br />
ie reset switches<br />
parallel copiers<br />
old old computers (pre- c64)<br />
<br />
then please contact me<br />
<br />
<br />
GURU/TSR<br />
-code swap<br />
xxxxxxxxxxxxxxx -code letters<br />
teralba nsw 2284 -elect. swap<br />
australia -elect. letters<br />
-elect. info<br />
<br />
<br />
<br />
<br />
THIS CHAPTER WAS NOT BORING<br />
<br />
AND WAS NOT A WASTE OF TIME<br />
<br />
<br />
<br />
fire if you dare</pre></div>Jazzcat