[time-nuts] Oscilloquartz BVA has been sold. Thank you all who expressed an interest.

[Mark Spencer]

Pondering the backup power issues for my BVA a bit more,  I am thinking a dedicated DC battery bank (maybe 5 or 6 nominal 6 volt batteries in series) powering a suitable linear regulator circuit is probably the direction I will go in.  I suspect there are more elegant and or simpler approaches but I think from my perspective as a hobbyist this is probably the best direction for me.  

I like the idea of using a diode arrangement to facilitate changing the power source for the BVA.   I expect I will also add some form of over voltage protection as well.

I need to ponder the likely voltage drops in the voltage regulator and diodes along with the voltages the batteries will provide as they discharge under load.  

It seems I have another winter project.

Thanks all for the suggestions.


Mark Spencer
mark at alignedsolutions.com
604 762 4099

> On Sep 25, 2020, at 7:16 AM, Magnus Danielson <magnus at rubidium.se> wrote:
> 
> Hi,
> 
> On 2020-09-24 23:47, Tom Van Baak wrote:
>>> Next time I power down mine is to integrate a new supply and back-up
>> 
>> May I recommend PowerPole connectors and frequent use of diode-OR. For
>> details see:
>> 
>> http://leapsecond.com/pages/powerpole/diode-or.htm
>> 
>> I got the inspiration when my Dad was in the hospital and I saw how
>> they did IV tubes with multiple injection points. It seemed so simple,
>> clever, reliable. Details [1] and graphic photo [2].
>> 
>> So now I use diode-OR "Y" connectors on all my long-term standards. It
>> allows me to replace either power supply live without interruption at
>> any time. Come to think of it, they call it an IV in the hospital. And
>> here in my lab the I is about 0.18 and V is 24 so my IV is 4 watts. ;-)
> That's how we do it in Telecom, but on the 48V level. I managed to drive
> my company into do it with 48V all the way to the various boards,
> because that way the protection switching out there handled multiple
> faults. Also, for some reason there is this line of DCDC converters from
> 48V to about anything. We kept doing that since, even if the diodes now
> been replaced with MOSFETs to lower losses.
> 
> If you look into say the 5065A that's how it's done there too.
> 
> As for power-pole, those are great connectors, but I need to keep 12V,
> 24V and 48V in the lab, so I need to get the different color codes not
> to interchange them. You usually react when you see a yellow-black
> trying to mate with a red-black. So, I recommend folks to do the same.
> Once one got started with the Anderson PowerPole, it becomes more and
> more a solution.
> 
> But yeah, thanks for reminding me that I need to progress on the
> power-pole and power supply projects. I'll do that after the PiDP-11
> project.
> 
> Cheers,
>