Hello,

I finally got my circuit working... well almost.
I use a pic chip with picbasic pro, I output DTMF and this goes
through a filter shown in picbasic manual:
http://www.melabs.com/resources/pbpmanual/5_17-5_21.htm
From my scope I can see some 40v spike at the pin output and after the
filter I do not see much maybe a few volts.
This goes directly to an audio transformer.
Is it normal to have 40v spike (the signal looks pretty nice). WHen I
put a modem speaker at the pin output I can hear the dialing and maybe
a third in strenght (sound) after the filter. At the output of the
transformer I have an AC 250v capacitor. The pichip dials my phone,
and I receive maybe 50% of the calls.
Should I be using the filter? (I am not using an amplifier as
mentionned in the manual)
Is the 40v good to put directly on the transformer?
Also from the speaker I hear a lot of background noise

thanks
k
Assuming you have the correct voltages around the PIC, you have