Schematic differences are odd indeed. However, I'd suspect at it's age, you've likely got a "leaky" portamento cap that needs replacing. Looks like 15uf on my prints. A bad 741 is also possible. And if anyone else has ever been inside this guy, they may had put wires on the wrong pins.
Hope that helps.
--- In emlsynth@yahoogroups.com, "steve13dejesus" <sdejesus13@...> wrote:
>
> Hi all,
>
> I have an EML 101, S/N 278, that is in perfect condition except for some strange behavior in the glide circuit. With the glide knob fully counter clockwise, everything works as expected. With the glide knob turned even slightly clockwise, I get no sound except for some very low frequency clicking.
>
> I looked inside the unit and compared it to the hand drawn schematic and the nicely modernized version of same drawn by David Hillel Wilson. My glide circuit shows significant differences from the schematic.
>
> The glide pot in mine is a 10 Meg mod pot instead of the 1Meg shown in the schematic. It tests fine both across the fixed leads and from the wiper to each fixed lead.
>
> There is a diode connected between the common connection of the wiper and one fixed lead and ground (the front panel itself) that is not present on the schemo.
>
> I can find the wires that go from the two fixed leads of this pot to the Glide switch jack. Following other wires from these fixed leads on the pot to the circuit board and trying to relate their connection points to the two op amps shown flanking the pot in the schemo shows more differences, like a cap between the left hand op amp pin 6 and the pot and also a 1k resistor connected to that cap.
>
> Does anyone know what I am looking at here? It looks like a whole different glide circuit than what is in the schemo. Was there another version? None of the circuitry looks like it has been modified - all of the construction looks to be of the same vintage and quality. Any idea what is going on when I turn the knob?
>
> Many thanks for any info you can share.
>
> Steve DeJesus
>