[time-nuts] Digital Mixing with a BeagleBone Black and D Flip Flop

Simon Marsh subscriptions at burble.com
Tue Oct 14 12:34:16 EDT 2014


Yes, I do understand I'm asking for trouble, though I kinda expected to 
see more noise rather than less.
I guess its time to break out the soldering iron.

Cheers


Simon

On 14/10/2014 17:22, Robert LaJeunesse wrote:
> Using 74AC parts on what I think of as a pluggable breadboard (e.g. http://uk.farnell.com/jsp/search/productdetail.jsp?SKU=2295705&MER=bn-me-ca-r1-best-sto-5) is asking for trouble. The parts are RF fast and the pluggable board has not very good contact resistance and certainly more inductance and shunt capacitance than is good for RF. I would highly recommend using dead-bug style on a solid copper plane, as provided by a chunk of unetched PCB material. (Jim Williams did a few like that, see http://1.bp.blogspot.com/-y3xQiBHHzaQ/UP3mLk96qWI/AAAAAAAAAss/ZvPbfN8lmTQ/s1600/eep114.jpg.) This approach allows for extremely short lead lengths and power supply bypassing (to the plane) with a near zero lead length capacitor.
>
> Bob L.
>
>> Sent: Tuesday, October 14, 2014 at 11:32 AM
>> From: "Simon Marsh" <subscriptions at burble.com>
>> To: "Discussion of precise time and frequency measurement" <time-nuts at febo.com>
>> Subject: Re: [time-nuts] Digital Mixing with a BeagleBone Black and D Flip Flop
>>
>> ... 74AC74 ... knocked up on some pluggable breadboard
> _______________________________________________
> time-nuts mailing list -- time-nuts at febo.com
> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> and follow the instructions there.




More information about the time-nuts mailing list