[time-nuts] Re: HP Z3801A project update

[Bob kb8tq]

Hi

One would guess that they delay going “full power” so as not to hammer the
main power supply quite so hard at start up. 

Bob

> On Jan 29, 2022, at 2:27 PM, Tom Holmes <tholmes at woh.rr.com> wrote:
> 
> HI Ed & Ed...
> 
> Thanks for the plot. The dive towards zero just before the spike s surprising; maybe a funky data point?
> 
> Anyway, I'm not doubting that the observations are correct, just curious about the timing and source of that power spike. Like maybe the controller decided it wasn't heating fast enough?
> 
> Tom Holmes, N8ZM
> 
> -----Original Message-----
> From: Ed Palmer <ed_palmer at sasktel.net> 
> Sent: Saturday, January 29, 2022 11:07 AM
> To: time-nuts at lists.febo.com
> Subject: [time-nuts] Re: HP Z3801A project update
> 
> On 2022-01-29 2:30 AM, "Tom Holmes" <tholmes at woh.rr.com> wrote:
>> Ed...
>> 
>> Very good data!
>> 
>> I am curious about one part of the warmup process. At around 7 minutes, the power jumps up radically, which you attribute to
>> the outer oven kicking in. It has often been stated on this list that the outer oven was intended for use during really cold
>> starts, which I would expect should cause it to kick on almost immediately during a very cold start. I am assuming your start
>> was from room temperature. For a room temp start, I wouldn't expect it to kick on at all  if it's purpose was as reported. Or
>> do I have the oven functions reversed?
>> 
>> Tom Holmes, N8ZM
> 
> I can confirm Ed's tests.  Attached is a similar test that I did on my 
> Z3801A.  If it matters, mine is the 24V nominal version.  My test was 
> done at 27V.  The power supply was an HP6622A with GPIB.  I wrote a 
> program to query the current being drawn each second.  The current value 
> was later converted to power.
> 
> Ed
> 
> 
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