Should a BBD pass signal without a clock?

Started by strungout, August 12, 2021, 07:53:10 PM

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strungout

Just to makes sure.

I've built a boss BF-2. If I jumper pin 3 (input) and pin 7/8 (combined outputs), the signal makes it to the circuit output, but with the BBD in (MN3207) nothing comes out at pin 7/8. The bias trimpot does vary the voltage to pin 3 but, I can't bias it because I can't hear it. I know the BBD works, I popped it in my flangelicious and it worked just fine. So, it's my connections. But that question in the title's been bugging me...
"Displaying my ignorance for the whole world to teach".

"Taste can be acquired, like knowledge. What you find bitter, or can't understand, now, you might appreciate later. If you keep trying".

ElectricDruid

No, a BBD can't pass a signal without a clock. And not without a good quality clock at that. In order for it to get from one end to the other of a 3207 in a reasonable state, over a thousand individual hand-overs from one set of caps to the other set have to occur. If both sets of switches are on at once, your signal will die the "death of averaging". It's more-than-somewhat amazing that it ever works at all, tbh.

Tom

strungout

Alright, thanks Tom.

So, this means my clocks are shit. Merde.
"Displaying my ignorance for the whole world to teach".

"Taste can be acquired, like knowledge. What you find bitter, or can't understand, now, you might appreciate later. If you keep trying".

PRR

#3
Bucket brigade at work:

https://www.youtube.com/watch?v=EGWEIvMsWhg

Here, the bucket-passers have brains and can see each other. In a dumb chip, you have to shout "Now! - Now! - Now!" to keep the bucket passes in sync and not colliding. If you don't "Now!", the first guy just stands there waiting for a sign.
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anotherjim

If you measure both BBD clock pins for DC volts, a good clock signal will show about half the supply voltage. Both clocks should give identical results.

Mark Hammer

#5
Quote from: strungout on August 12, 2021, 08:20:11 PM
Alright, thanks Tom.

So, this means my clocks are shit. Merde.
Maudit horloge!!

Car c'est Québec, d`habitude un des syndicats serait probablement en grêve.  :icon_wink:

Vivek

Quote from: strungout on August 12, 2021, 08:20:11 PM
Alright, thanks Tom.

So, this means my clocks are shit. Merde.

Digital clocks dont have any hands on experience !!

strungout

lol thanks for the laughs, guys!

That firemen competition is intense.

I ended up getting Steve's last few BL3102s. Those should work. At least I know they'll be good. I'm getting a refund for the other chips I bought (only 4/10 MN3207 work and none of the 10 MN3102 do).
"Displaying my ignorance for the whole world to teach".

"Taste can be acquired, like knowledge. What you find bitter, or can't understand, now, you might appreciate later. If you keep trying".

ElectricDruid

Quote from: strungout on August 14, 2021, 02:45:44 PM
(only 4/10 MN3207 work and none of the 10 MN3102 do).

Ouch! That *is* a pretty sh!t ratio! Those are not good parts!