[time-nuts] Thunderbolt Supply

Bob Camp lists at rtty.us
Tue Feb 15 13:04:54 UTC 2011


Hi

The same board with all the logic crud on it has the 10 MHz signal amps on it. Same supply / same ground for it all. There very much is a practical limit here.

Bob


On Feb 15, 2011, at 4:47 AM, Magnus Danielson wrote:

> On 02/15/2011 04:18 AM, Charles P. Steinmetz wrote:
>> Bob wrote:
>> 
>>> If all you are doing is running a Thunderbolt, you don't need a supply
>>> that's more quiet than most batteries.
>> 
>> Most batteries are *very* quiet -- it takes heroic measures to get *any*
>> actively regulated supply into that ballpark. Indeed, one might be
>> tempted to run a Tbolt off of three batteries, each one charged by a
>> low-noise, high-impedance current source that puts out about .05 CV more
>> than the Tbolt draws. One could even turn the charging off for short
>> periods of "minimal noise" operation, if the batteries were suitably
>> sized. However, in either case I would be concerned that the drift of
>> one or more of the battery voltages (poor absolute regulation) might
>> introduce another source of XO drift -- but I have not tried it.
> 
> This has gone overboard. The T-bolt generates digital noise all by itself. It's the OCXO which would benefit most from a clean supply and isolation from the rest of the T-bolt except that temp-sensor.
> 
> Providing ultra-clean supplies to the digital logic would be overkill, as it would mess it up itself anyway.
> 
> Cheers,
> Magnus
> 
> _______________________________________________
> 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_lists.febo.com mailing list