Re: Echo IIb sound fried

[Rubywand <rubywand@swbell.net>]

Theresa Fiori writes ...
> 
> I have a Echo IIb sound card with the original speaker.... just recently
> I was moving my Apple IIe to make room for a bulletin board (it's
> cramped where my Apple IIe is). I booted everything up and I heard
> nothing from the speakers. I had to resort to using the little speaker
> under the keyboard..... please help! It worked fine before. Can anybody
> troubleshoot this? It would be a great help. Thanks.
> P.S. I wanted to remove the little speaker to sell as an extra part. How
> do I get the d**m thing out?

     We had to move the one in our II+ several years ago to make room for a
power supply replacement. Don't recall how you detatch the speaker. If a close
inspection from the top does not indicate a simply way, check for any bolts
coming in from the bottom.

     In most cases, removing the speaker is not a good idea. (We moved the one
in the II+ to a new space and used double-sided tape to reattach it.) Having
the small internal speaker in place and connected does not hurt anything; and,
it is a handy indicator of correct operation-- e.g. the BEEP you get on
startup, for Resets, etc.-- which does not depend upon having any Slot boards
plugged in.

     Echo installation includes a connection to the leads going to the internal
speaker. So, the "old Apple II sound" (like BEEPs and game sound effects) is
probably supposed to be available from the Echo. However, this does not
necessarily mean that you are free to remove the internal speaker.

     I have never installed an Echo card and do not know anything about Echo's
input circuit for the signal coming from the internal speaker. Most likely, the
input has a fairly high impedance-- that is, it 'looks like' a high resistance.
If the Echo input is coupled via a capacitor, you have what amounts to a very
high DC resistance.

     My guess is that the Apple II sound output circuit will not function
correctly with Echo unless the internal speaker is connected or some small
resistance (like a 15 Ohm resistor) is substituted for the speaker. Something
like ...


Speaker Leads

------o----------| /
                 |<  Speaker
------o----------| \

or

------o----------|
                 Z  15 - 22 Ohm resistor (about 1 Watt)
------o----------|

o = connections going to Echo


     Besides the above, the usual reason a sound card or box might not have any
output is a messed up (shorted or broken) cable. You can use an Ohm meter to
check your cables for shorts and breaks. Some sound peripherals use a battery
which needs to be replaced every so often.



Rubywand