crchisholm wrote:I think I got a dead speakjet. I tried to use the simple demo circuit and got nothing from the chip. The demo schematic shows a 120 ohm speaker and I think they must mean 12 ohm. I didn't have a 12 ohm but tried a 10 and an 8 and neither gave me anything. Did I screw up or is it possible the chips is just dead?
I think they were serious about the 120 ohm speaker. I think this would be a headphone type speaker.
An 8 ohm speaker might have ruined you chip.
I used mine with a Veho 260 powered speaker. I think you could use the SpeakJet's output to drive the "line in" port of a computer speaker.
I posted a video of my SpeakJet chip driving the Veho 360 in post #9 of this thread.
http://forums.parallax.com/showthread.p ... ost1107447
The picture of the breadboard isn't very clear, but it might help you some.
I connected the SpeakJet's output to the tip of the 1/8" connector and the sleeve to ground.
It's often a good idea to have the signal pass through a capacitor before it connects with the speaker so it only passes the AC portion of the signal.
IIRC, I was able to get sound from the Veho speaker by both directly driving it from the SpeakJet chip and also with the speaker capacitively coupled with the SpeakJet chip.
FYI, Parallax has just come out with a new text to speach module, the Emic II.
http://www.parallax.com/StoreSearchResu ... fault.aspx
It costs a little more than using the SpeakJet and TTS256 chips combined, but it produces much better quality speech and has nine different voices.
Monday is the first day they'll be shippping these.
