[time-nuts] HP E1938A Oscillator

[Ed Palmer]

On 7/5/2013 3:00 AM, Bruce Griffiths wrote:
> Magnus Danielson wrote:
>> Hi Perry,
>>
>> On 07/05/2013 07:23 AM, Perry Sandeen wrote:
>>>
>>>
>>> List,
>>>
>>> I was looking on Ebay for some HP E1938A
>>> oscillators
>>>
>>> What I found listed were:
>>>
>>> HP E1938A 10 MHz Quartz Oscillator with EFC on PC
>>> board. $100 Fluke.l
>>>
>>> HP E1938-60201 Ovenized Crystal Oscillator  (on a PC board) $100 
>>> Tomy Chou
>>>
>>> HP E1938A Ovenized Crystal Oscillator  W/O a PC board for $50 and 
>>> free shipping from  2010bluebook.
>>> My question is thus:  What does the PC board do?  All I need is a HP 
>>> EFC oscillator that would
>>> be better that my HP 10811-60111’s.
>>>
>>> Do I need to worry that the E1938A’s without the
>>> board maybe of lessor quality than the others?
>>>
>>> Fluke.l says his units are good but not stellar.  The other venders 
>>> say they have tested the
>>> units and guarantee them to be good.  If
>>> so, would it get better with aging?
>>>
>>> So what does the collective wisdom/experience of
>>> the group think?  TIA
>>
>> Don't get the puck only. Pulling it from the board with all it's 
>> support functions, including oven controller etc. was a bad move. Do 
>> look at the material online to see what I mean.
>>
>> Cheers,
>> Magnus
>>
> However the pucks can be a useful replacement when an E1938A 
> oscillator fails as one of mine did.

I noticed that the circuit board and the puck are labelled with each 
other's serial number and that various pucks are labelled with 
significantly different temperature values.  When you change pucks or 
boards do you have to adjust or reprogram the board to match the new puck?

Ed