[time-nuts] 15 volt power supply for FE-5680A on eBay

[EWKehren at aol.com]

Pete
Thank you this is valuable info. I noticed that an effort is underway to  
centralize info on the 5680. Would be nice if some one with time and software 
 expertize would combine all the information. I cut and paste what ever I 
find on  the list and will be glad to forward it to a volunteer. This kind of 
findings  should be included. 
Bert Kehren
 
 
In a message dated 1/18/2012 8:47:54 P.M. Eastern Standard Time,  
bell.peter at gmail.com writes:

One of  the regulators (the one that runs the lamp and lamp heater) is
running at  13.8V and has a 500mV dropout voltage, so there is very
little (~ 700mV)  headroom. The one that runs the cell heater is about
a volt lower and the  one that runs the analog circuits is set to 8.8V,
so has plenty of  headroom.

I suspect the lamp regulator is mostly there to reduce the  start-up
current, though - the FE-5650 has a very similar lamp circuit with  no
regulator and the only significant difference seems to be that  the
current pulled when the unit is cold is  higher.

Regards,

Pete Bell


On Thu, Jan 19, 2012 at  8:19 AM, paul swed <paulswedb at gmail.com> wrote:
> I think it is  important. The specs say 15-18V.
> So I would not drop below the spec.  Though interestingly pretty much
> everything inside the system is using  switching supplies so perhaps there
> is more room.
> The gtood  thing about the switchers is that as the input V goes up 
current
>  should go down if that helps you.
> Regards
>  Paul.
>
> On Wed, Jan 18, 2012 at 6:25 PM, Chris Albertson
>  <albertson.chris at gmail.com>wrote:
>
>> I used a variable  voltage bench supply to experiment.  tried low
>> voltage like  you are seeing on my FE5680 and I never got a lock.   The
>>  FE5680A spec sheet says 15 to 18 volts and I think you can get buy
>>  with 14.5V.  i tried 12.5 and got "nothing"
>>
>> I did  not test to find the "breaking point"  But 1/2 volt low was  OK
>> and 2.5V low was not ok.
>>
>> What I bought  is a 15V open frame supply from allelectronics.com for
>> $11.50.  It turned out to be a very high quality power supply  (Digikey
>> has the same unit for almost $40)   This PS does not  drop volts even
>> with the line input and load  well out of  spec (I tested 63VAC input
>> to a 4A load briefly)  I added an  RF "hash" filter "just because I
>> could"  and then an LM7805  and I think I'm OK.
>>
>> I thought about making a linear  supply for the cleanest power but i
>> intend to run this 24x7 and  don't like wasting so much power.
>>
>> This is the one I  bought
>>
>>  
http://www.allelectronics.com/make-a-store/item/PS-152/15VDC-2.7A-POWER-SUPPLY/1.html
>>
>>
>>  On Wed, Jan 18, 2012 at 3:05 PM, Paul F. Sehorne <paul at sehorne.org>  
wrote:
>> > How important is the 15vdc at the initial startup  2amp, and then how
>> > important at the .7 amp settled  rate?
>> >
>> > I just received two of  these
>> >  http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=280439877318
>>  >
>> > Unloaded voltage is ~15.5vdc.  At 700 ma voltage  drops to 14.3 volts 
and
>> > with 2 amp load drops to 13.3 volts  with a 2 amp load (and to 10 volts
>> with
>> > a 5 amp  load).  Supposedly rated at 6 amps.  I have only checked  one,
>> have
>> > not broken the packaging on the second  one assuming its performance 
will
>> be
>> >  similar.
>> >
>> > Will this be a problem?
>>  >
>> > Paul
>> >
>> >  _______________________________________________
>> > 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.
>>
>>
>>
>>  --
>>
>> Chris Albertson
>> Redondo Beach,  California
>>
>>  _______________________________________________
>> 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.
>>
>  _______________________________________________
> 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.

_______________________________________________
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.