[LectronFanModerator]

Hi all,
Let’s have some retro fun with the legacy components.

I picked a random circuit of the legacy Braun Lectron Computer techniques manual.

It’s circuit 97 : Feeding a flipflop from a slow charging capacitor.

At first glance, the meter only shows the schmitt trigger switching and it really happens too fast to notice !

Let’s tweak and expand it !

I’ve added a transistor buffer and feed the slow charging to the meter.

Any idea why we use an emitter follower ? Hint: we have already used this kind in several circuits posted on this forum !

Now, you can actually see the charging voltage. I’ve also increased the charging time by using 2 resistors of 100K in series (R2 & R3).

The components chosen around T1 make the reading of the meter indicating the threshold of the schmitt trigger U1. If you build the circuit, note down the reading when the U1 gets activated. Which multiplier should be used for the reading ?

Do you think we can also use the transistor with the 100K resistor build in for T1 ?

Place your comments here !

Here’s the circuit :

Many greetings

• This topic was modified 5 years, 2 months ago by LectronFan.
• This topic was modified 5 years, 2 months ago by LectronFan.
• This topic was modified 5 years, 2 months ago by LectronFan.

[Author]

Posts