[sdiy] Gate outputs.. 0v or ground?

[Seb Francis]

Hi Mike,

Every v-trigger gate output I've ever come across is low-impedance 0V 
for "Off".

However (in most cases) v-trigger gate inputs should also assume "Off" 
for open-circuit input (i.e. if you don't have anything plugged in).  
You could achieve this is in a number of ways (e.g. switched jack socket 
connecting input to GND, pull-down resistor to GND, etc.)

Seb


Mike Beauchamp wrote:
> I have a simple question about gate inputs, but no hardware to quickly 
> check...
>
> When a gate output (or v-trigger) is LOW, it's at 0 V right? Does that
> mean it is "open circuit", or grounded, or somewhere inbetween? If
> it's inbetween, what is the resistance to gnd?
>
> I'm building a super-simple VCO and I want it to be able to respond to
> a gate signal to tell it when to actually output audio. I'm also
> working on a really simple switch that can output the gate signal, and
> I don't know if I should be grounding the output when the signal is
> LOW, or just leaving it open circuit, or having some resistance to
> ground. I'm also wondering if maybe I should be buffering my gate
> output?
>
> The way my VCO works right now, it responds to a gate signal that is
>> 2V for HIGH and GND or around 100K resistance to gnd for LOW. If I
> leave the gate input open circuted, the VCO assumes gate is also HIGH.
> So you can see how if standard gate signals go from example 5V HIGH
> and open-circuit LOW, my VCO won't make a distinction.
>
> Thanks in advance..
> Mike
>