[sdiy] Now tube type (6SN7) flip-flop circuit.. Follow up...

[Donald Tillman]

> On Feb 1, 2024, at 7:20 AM, Jean-Pierre Desrochers <jpdesroc at oricom.ca> wrote:
> 
> The problem I have is the following :
> For example if you look at the 2nd freq divider,
> To produce a going down pulse at V3-pin 5 you need
> A going up pulse generated by the preceding FF stage output.. here V4-pin2. Ok.
> But to make all the following freq dividers ‘in phase’ each FF’s
> should produce a going up pulse at their outputs to drive the next connected pre-driver/inverter..
> (FF’s outputs are : V5-pin2, V7-pin 5,  V9-pin 2 and… oupss !!! they chose V10-pin 2 instead of  V10-pin 5 !!!) Why ???

Each divider stage uses three triodes.  And a 6SN7 has two triode sections.  So, 1-1/2 tubes per divider stage.  The tube sections are interchangeable, so the specific pin numbers aren't important.  Perhaps they found it easier to wire them one way or another.

> Despite the fact Hammond chose pin2 instead of pin5 of V10 on the last FF,
> And following my first interrogation on transistor FF’s on how they start at first
> How can I understand what makes all these freq dividers allign ?

The divider stages don't actually "align" as such.  It doesn't matter what state they start in.

Each divider stage is responsible for changing state, from whatever that state was, when its input from the previous state goes high.  

So for any given divider stage, from his point of view, all the previous divider stages go through their stuff, twice.

  -- Don
--
Donald Tillman, Palo Alto, California
https://www.till.com