[time-nuts] HP 5061A Cesium Beam Reference For Sale

Skip Withrow skip.withrow at gmail.com
Tue Apr 25 16:55:40 EDT 2017

Hello Time-Nuts,

I acquired a number of 5061A and 5061B chassis (some with tubes, some
without) plus a number of tubes - all in various states of unknown working
condition.  After going through the tubes to find working ones I have
started to piece together working units.

I currently have a 5061A working that is excess to my needs.  I went
through the chassis and replaced or repaired any non-functional modules,
selected a random working tube (this one is very old, but is working fine),
set the A11 oven temperature, electron multiplier voltage, hot wire ionizer
voltage, loop gain, and 2nd harmonic level.  And have set the C-field to
put the unit on frequency (or nearly so, 95ns in 41.6 hr = 6.34x10E-13).  I
have the 41 hour plot that I can send to prospective buyers, as well as
pictures of the unit.

The 5061A has 5MHz, 1MHz, and 100kHz outputs (the 5061B adds 10MHz), but
there is a 10811 oscillator in the unit that does have 10MHz coming out of
it.  This unit does have the battery option, but the battery is deader than
a door-nail.  There are no top or bottom covers, or rack mount flanges.

I'm offering it to the time-nut community at what I believe is a reasonable
price - $750 plus shipping from Denver, CO.  If interested, please contact
me OFF LIST.  List member Paul Swedberg has a previously resurrected unit
and he seems to be having fun with it.

Thanks in advance.

Skip Withrow

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