Vytec diy interface

[Aquamaniac]

froop once bubbled...


There's not much use in measuring the voltage while the circuit is in transfer mode, as the voltage will be changing 2400 times a second!

When doing test #1, if you're measuring the voltage with the negative terminal on ground, and the positive terminal on the IO contact, the voltage should actually be -3v, not +3v as the instructions say. (+3 volts is actually impossible, if the circuit is built properly!).

If the voltage reads anywhere between about -2.5v and -5.5v you it should work OK.

When you start the PC transfer, the up and down ceiling arrows on the computer display should start flashing. This is a good indicator if something is getting through the interface..

Same thing happens when you stick your meter in the wall receptical. Its changes voltage ifinitly every .016 seconds, then it repeats itself. At one point there is actually NO voltage! The same pattern occurs 60 times every second. Amazing really.

(Im very bored)

 

[jamiei]

yes... 60 hertz I believe... take a single white chirstmas light and hook it up to a lamp cord and plug it in... then spin it around in a circle... you can then see that the bulb is actually flashing and not steady... 60 times a second. What can I say... science methods class.

 

[jamiei]

Guys, I found my problem... the blasted pin orientation was different in the last batch of transistors I bought... they must have changed it because i bought them from the same place and same stock number... well, I have about 6 interfaces available now...