[sdiy] Moog Taurus 1 schematic questions

[Kevin Lightner]

>Hello folks
>
>I've been trying to decipher the Moog Taurus 1 schematic at 
>Synthfool. The schematic contains some mystery resistors (R204, 
>R206, R208 in VCA EG) that have no values shown and only the text 
>"Not on board" shown in the marginal. What should their values be?
>
>Am I correct in that "sustain" is actually simply "volume" and that 
>the EGs are always AR?
>
>Also, what's with the IC*** gray components that seem to contain a 
>precision resistor and trimmer? Can I just replace them with normal 
>resistors?
>
>Antti
>
>"No boom today. Boom tomorrow. There's always a boom tomorrow"
>   -- Lt. Cmdr. Ivanova


Some trimmers have integral resistors on them.
Film on ceramic 1% types.
Standard Cermet trims can be used, however you will have to make your 
own resistors externally.
Keep in mind that these resistors need to be 1% or better and 
matching either to spec or to adjacent like trim replacements is 
recommended.

I'm not totally sure on the "sustain" issue, but it might be so.
There are several things that are weird on T1's.
For example, the two attack stages have different ranges, the pedals 
are wired in daisy-chained fashion requiring ALL pedals below a 
desired not to have their contacts closed, they're linear vcos (and 
can be dropped down an octave very easily by replacing their caps 
;-), don't necessarily trust their "use a 4066 instead of a 4016" 
talk, leds suck current and can be replaced with better ones, etc.

Usually unmarked resistors in Moog's point to their usage of resistor networks.
Some are standard types with all resistors the same values and 
paralled or serially wired with taps.
Others follow log values or are simply custom made.


-- 
Regards,
Kevin Lightner

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