i am glad i used a socket! i try to do that every time, it seems to avoid a world of hurt.
i tested the voltage on pin 6 and did notice a change when i turned the trimmer. the
voltage was kind of low, i am not sure what to expect there. i also noted that on pin 7, i
saw roughly the same behavior as on pin 6.
i have looked time and time again for a short, and it seems clearly lacking one...but i really
could go through my resistor values again, and will do that next. are there any in
particular i should take the most note of in this circuit?
i have re-checked my tube, and i am very confident that the pins are right. thanks for
making me look though... it was a lingering concern.
i appreciate all the help, thank you!
-michael
i tested the voltage on pin 6 and did notice a change when i turned the trimmer. the
voltage was kind of low, i am not sure what to expect there. i also noted that on pin 7, i
saw roughly the same behavior as on pin 6.
i have looked time and time again for a short, and it seems clearly lacking one...but i really
could go through my resistor values again, and will do that next. are there any in
particular i should take the most note of in this circuit?
i have re-checked my tube, and i am very confident that the pins are right. thanks for
making me look though... it was a lingering concern.
i appreciate all the help, thank you!
-michael
--- In cgs_synth@yahoogroups.com, "bbluthang" <jumpswine@...> wrote:
>
> bet you are glad you used a socket.
> With no chip in the LM358 socket, check the voltage on pin 6 of the
> socket and adjust the trimmer, does the voltage change? If so, at
> least your CV input should be okay.
>
> With the chip, if it gets hot, suspect a short somewhere or possibly
> a resistor is incorrect.
>
> Maybe it is worth mentioning, have you got the tube pins wired in
> the right order? it can be confusing (I say this from experience :-
> )) if you are new to tubes.
>
>
>
>
> --- In cgs_synth@yahoogroups.com, "prophei" <prophei@> wrote:
> >
> > --- In cgs_synth@yahoogroups.com, "bbluthang" <jumpswine@> wrote:
> > >
> > > Have you tried to set it up as per Ken`s instructions?
> > >
> > > SetInitial Gain pot to 0, no CV in, feed in an audio signal and
> > > adjust the trimmer until you cannot hear anything on the output.
> > >
> > > Once you have done this, plug in a CV signal and adjust initial
> Gain
> > > to get it VCAing as you like.
> > >
> > > If you have tried all this, and still no effect. What voltage
> are
> > > you getting on pin 1 and does it change when you adjust the
> initial
> > > Gain pot? (It should!)
> > > cheers
> > > Andrew
> >
> > i just went to test pin 1 of the lm358, and found nothing there.
> then i somehow blew the
> > ferrite bead (i had a resistor here) located next to the cv inputs
> to the board. i have no idea
> > how i did this, and want to think it was pure coincidence (tho
> this may be a rather unlikely
> > thing). all i have ever been able to measure around this ic has
> been positive and negative
> > power (on pins 8 and 4 respectively).
> >
> > i replaced the blown bead (resistor) mentioned above and then
> swapped the lm358 for a
> > 5532 i had sitting here to see what would happen. this chip gave
> me actual readings on
> > the pins. pin one was registering a 12.5. i still was unable to
> get anything to work
> > properly, and noticed that the 5532 seemed rather warm, so i
> pulled it and quit for now.
> >
> > i sit here scratching my head yet again.
> >
>