[time-nuts] Lady Heather numbers

Garren Davis garren.davis at qlogic.com
Tue Mar 12 20:01:54 EDT 2013


I checked the current on the oven. It seems to be operating correctly. My theory is
that it worked before it was shipped. This was from the TAPR group buy. They were all
tested before shipping. The resistor probably popped of during shipping. The other
resistor popped off probably from me unsoldering the board from its standoffs and
flexing it in the process. Maybe it was a bad solder job at the factory.

Thanks for the comments.


-----Original Message-----
From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On Behalf Of Rex
Sent: Tuesday, March 12, 2013 4:35 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Lady Heather numbers

Do you think that the oven is working correctly? Is the DC current high on power-up then dropping to a steady lower value after warm-up time?

My concern is that the resistors may have unsoldered themselves because the oven ran away into an over-temp condition.

On 3/12/2013 9:55 AM, Garren Davis wrote:
> Bob,
> Took your advice and ordered another OCXO. While waiting for it I decided to cut open the
> OCXO with a bad heater that came with the thunderbolt. I found the 1 ohm resistor from the
> 12 volt pin to the heater circuit popped off its solder pads and was laying between the
> insulation and the metal enclosure. While unsoldering the circuit board to fix this the
> 1 ohm resistor in the oscillator circuit popped off its solder pads. For others that have
> OCXO's that don't work this is an easy fix. They are large surface mount resistors and easy
> to solder. Anyways I put the circuit board back in the metal enclosure but did not seal
> it. I put the OCXO back in my double oven and started a run. The enclosed picture is a 72
> hour display. Even though the DAC was still increasing it looked like the PPS had stabilized
> so I did an auto calibrate. You can see this at marker 1. That was almost two days ago.
> Questions:
> 1. Is it normal to take this long for the PPS to stabilize?
> 2. Is it normal for the DAC to keep increasing after two days?
> 3. In general what numbers would be considered good for the PPS and OSC?
> Thanks.
> Garren

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.


This message and any attached documents contain information from QLogic Corporation or its wholly-owned subsidiaries that may be confidential. If you are not the intended recipient, you may not read, copy, distribute, or use this information. If you have received this transmission in error, please notify the sender immediately by reply e-mail and then delete this message.

More information about the time-nuts mailing list