Hmmm. I managed to clean the output of the PWM and get a VERY stable output reading from the fv counter for the 1/100 level.
But I could not make it to 1/1000. I tried many ways.
First I hooked up the 1/100 board I just built to the breadboard with a 1/10. And it kept showing me the same output as the input. Very-Very strange. Logically you would expect another division. But noooo.
Then I said, blaimy, I leave only the breadboard circuit and tried to bring it down to 1/1000 as a single circuit. It didnt work because the fv counter can't count 0.x x x fv. It just stops at 0 and thats it. It actually jumps from 8 to 0. The most I could get it down was 2Hz, and I thought on a logical RC arangement of values to try for the 1/1000, that it wasnt working for the fv I had to test with, but MAYBE, it will work with the crystal.
Then I hooked up the crystal and ... nothing. I put it at 1/100 and it should have giving me something around 200kHz, what the maximum of this device could see, I was hunting for some variations at the border, but nothing. Then I tried a 14MHz crystal with also 1/100 model and it should had shown something. And it didnt. Then I tried my theoretical RC values for 1/1000 and nothing worked either. Also put both crystals and again, nothing. It was staying on 0 Hz all the time.
Then I measured the output of the circuit, oh, I used your circuit mister
@marconi with 1 transistor, and it give me 4V, so it was an output from that, no doubt.
I made so many permutations today, I am tired.
Funny story: I unhooked everything from the fv splitter circuit but I touched the input wire with my fingers. And the fv counter showed a clear 50Hz - hahahaha, I dont even have to plug it on the mains, I am vibrating at this fv anyway. Now that Im thinking it should have been 5Hz since it supposed to be splitting. I noticed sometimes, in certain conditions, the output is equal with the input of the fv splitter.
Then, I had another bright idea, to check the maximum fv of the 555 ! And I checked the internet, and it says "500-kHz to 2-MHz ", ok, then I looked in its datasheet and it says:
and I didnt find nowere the fv of the 555 mentioned in its datasheet. This values here, the 100ns are the only ones I could find and I thought I can convert that into Hz, and I did, and guess what, 100ns = 10000000Hz = 10Mhz . I beat the internet with this finding, but still not good enough for my 20MHz crystal. So.... Im screwed with this experiment. Its a test anyway. But I am not happy that logic splitting didnt work. It should had. I was counting on it. Eh well, life lesson, never expect anything.