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Re: Mocking board schematics

Polymorph wrote:

On Dec 9, 4:46 pm, Steve <srk...@gmail.com> wrote:


I expect this question has been asked before, but for the life of me I
cant seem to locate the Mocking board schematics at the usual array of
apple II sites.

Does anyone have a copy by any chance they could share?

Thanks,

steve



Steve,

I've come across a few different Mockingboard schematics over the last
few years, but here is one from the reactive-micro site (done by Bill
Garber):

http://www.downloads.reactivemicro.com/Public/Apple%20II%20Items/Hardware/Mockingboard_A/Technical/Mockingboard%20Schematic.gif


In this schematic, C3 and C5 can both be omitted, since the sound
generator chip analog outputs never go negative.

Also, since these are "line level" outputs, it's a good idea to
tie the outputs to ground through, say, 10k resistors, so that
the capacitors will have a DC path to charge.  (If they are
connected to a high-impedance line input, it could be many seconds
before the output DC level "settles".)


I can also send you copies of the other schematics I've saved too when
I get home if you're interested?


Here's the parts list, too:

>http://mirrors.apple2.org.za/Apple%20II%20Documentation%20Project/Interface%20Cards/Audio/Sweet%20Microsystems%20Mockingboard/Schematics/


I always thought it would be a neat project to build one of these, but
finding parts was a little difficult.


The AY-3-8910s are hard enough to find, but the SSI-263 speech chips
are almost impossible.  It's a good thing most people don't need speech!

-michael

NadaNet and AppleCrate II: parallel computing for Apple II computers!
Home page: http://home.comcast.net/~mjmahon

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