Hi Nicholas

> I don't understand the pot shown for soft sync connection, nor the
> required values for lin FM pot. If you did the mod, can you confirm
> that the typical A-100 component values will work here (b50k pot)
> Did you add the AC/DC switch or jumper And what is the soft sync
> pot for, is it a misprint

I used not a pot for the softsync input but a 47k resistor to ground
(equivalent to 50kpot fully turned clock wise). The pot is used to trim
the softsync signal in the kind of a threshold; the sync signal is fed
directly to the comparator, which triggers the unloading of C3; so if a
saw is used as sync signal the level of the sigal determines when and
how long c3 is resetted; if you use a narrow rectangle as sync signal, a
trimming is not required.

For the lin FM pot I used the 50kPot for the log FM (i simply removed R7
temporarily and connected the slider of the pot to R14. So I did not use
the cap and the switch. It depends on what you want to do with it.

> You also mentioned (I think it was you) the basic sine shaper
> Doepfer uses and a variation shown online.....those links don't seem
> to work anymore. Do you know of another example online I tried to
> find one but failed.

As far as I know there are sine shapers with several diodes in
antiparallel setup, but I do not know an online example for it.

> I don't suppose you did the A-120 input mod

I want to do so.

> Sorry to beat a dead
> horse here guys, but did YOU add the capacitor at C10 (I think, I'm
> trying to recall) as well as the resistor at R15, or just the
> resistor I've done it with the cap but haven't been home long
> enough to test it.

As far as I remember the schematic the change does make sense only, if
you have to add both (lower R and increase C). The RC pair is a passive
filter in principle. If you change only the resistor (to increase the
level of the signal), you change the cutoff frequency of this input
stage. So, to keep the frequency of this "filter" you have to increase
the capacitor.


Florian