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Re: IIGS Joystick issues

Drew wrote:

On 28 Aug, 21:35, "Bill Garber" <willy4...@comcast.net> wrote:

"Drew" <GoggleD...@gmail.com> wrote in message18a818cd-aa25-4523-92f5-fe6cf926f315@r66g2000hsg.googlegroups.com">news:18a818cd-aa25-4523-92f5-fe6cf926f315@r66g2000hsg.googlegroups.com...

On 28 Aug, 20:41, Drew <GoggleD...@gmail.com> wrote:




On 28 Aug, 20:14, "Michael J. Mahon" <mjma...@aol.com> wrote:

Drew wrote:

Adding a small capacitor inside thejoystickon (at least) the
vertical axis will compensate for the lower resistance and make
it work OK.

Hi michael,...without sounding very green...how would i do that :-). I
opened thejoystickand there are 2 wires going to each axis.

An earlier responder IIRC referred to the capacitor fix.
The cap can go between the two pot lugs for the vertical
axis that have the two wires connected. I'd start with
a failrly small value, like .005uF (5nF) and see what
difference that makes.

Thanks for responding will see what i can pick up capacitor wise.
Sorry for asking the same question that Ferdinand kindly responded
to...I have been playing with lots of things with my GS and had
forgotten that he had given me detail on the possible 2nd fix if the
calibration was out :-(.
Thanks
Andrew

Hi is this the kind of thing i want

http://uk.rs-online.com/web/search/searchBrowseAction.html?method=get...

Yeah, but pretty expensive. Are you in the UK.
I can probably dig out a 5nF and mail it to you,
for free. You might want to try Electronics
Goldmine and get a assortment for a $1 or $2.

http://www.goldmine-elec.com/

Bill Garber from GS-Electronicshttp://www.garberstreet.com


Yup I am in the UK. As you probably guessed my electronics knowledge
is minimal...though i am quite handy with a soldering iron :-). I have
been looking at Maplins in the UK and they are much cheaper, just
seems to be lots of options for types of capacitors which is beyond my
knowledge and havent been able to find one that is marked as 5nF...so
might take you up on your offer (but would definatley pay the
postage :-)).


Sorry for not mentioning that component values are often not
the "round" numbers that we usually think in terms of.  4.7 is
the usual value approximating 5, considering that the tolerance
on such capacitors is usually +/- 20%, or +/-10% for "good" ones!

This application requires only an approximation--the internal timing
capacitors in the //e are 0.022uF (or 22nF), and our objective is to
slightly increase the effective value.  Paralleling the pot with 1nF
would increase the readings by about 4-5%, which would probably be
plenty (you were getting 250 out of 255).  I suggested 5nF because it
is large enough to pretty much guarantee that your joystick will go
to 255 before reaching the end of its travel, and small enough to not
create too much of a "dead zone" at the high end of its travel.

Anything between 1nF and 5nF would probably work fine with your 'stick.

And Bill is absolutely correct about the price--these caps sell for
less than $0.10 in even modest quantities!  Much more than that, and
you are paying for the package.  ;-)

This is what an electronic "junkbox" is for...  ;-)

-michael

AppleCrate II: An Apple II "blade server"!
Home page:  http://members.aol.com/MJMahon/

"The wastebasket is our most important design
tool--and it's seriously underused."