[time-nuts] FE-5680 frequency jump

[Ed Palmer]

There's something in the back of my mind that MuMetal is easily 
magnetized.  If that's true, and if the FRS-C and/or FE-5680 cases are 
made of MuMetal (seems like a good chance), they should be demagnetized 
anytime they come in contact with a magnet.

Ed

On 4/5/2013 6:22 PM, EB4APL wrote:
> Thank you for the info, I used to attach a magnetic mount surface 
> thermometer to my FRS-C to check its operating temperature after 
> installing it in a box.  I think it is time to power it up and after 
> some days check it against the GPS.
>
> Regards,
> Ignacio EB4APL
>
>
> On 05/04/2013 20:59, Bob Quenelle wrote:
>> I found the cause of the 4 mHz  frequency jump.  I have an LPRO-101, an
>> FE-5680, power supplies and a Motorola M12T GPS board in a surplus case.
>> When I put the case away to work on another project I piled the hockey
>> puck antenna and lead in the case and it happened to land on the
>> FE-5680.  I noticed the antenna stuck firmly to the FE-5680 case when I
>> got the project back out.  I found I could get a 6 mHz (0.6 ppb) shift
>> comparing the frequency with residual magnetism from the magnet stuck on
>> the FE-5680 case to the frequency after demagnetizing the FE-5680 case.
>> Unintentional C field adjustment.  Dope slap, live and learn.
>> Bob