Name That Ware, September 2009

The Ware for September 2009 is shown below. Click on the image for a slightly larger version.

This Ware is again a user-submitted ware. I have a sneaking suspicion that someone out there will guess this one fairly quickly, even though all the naughty bits are obscured in the photo, but I think it’s a neat one because I’ve never seen the insides of one of these before myself.

20 Responses to “Name That Ware, September 2009”

  1. MegabytePhreak says:

    I’m going to guess it is a Cesium frequency standard. From the construction I would guess it is of early eighties to early nineties in origin, from a design standpoint at least. Although I can’t rule out late seventies either.

    • MegabytePhreak says:

      OK, got it. It’s a HP 5061B Cesium beam frequency standard. Nice piece of equipment. I appears that it may be running on a replacement Cesium tube though, since HP supposedly made their own.

  2. Mastro Gippo says:

    Mh.. I’ll guess it’s the inside of a satellite, for telecommunications.

  3. It’s a Datum Cesium Clock. A friend of mine had one of these that had been surplussed (sans cesium). Here’s some background…

  4. Adam says:

    its definitely a got standard clock, but i think its more than that, its got an ovenized oscillator block. i dont think that you need to ovenize a cesium clock, maybe the just the detection electronics.

  5. Jolly says:

    It’s a Cesium Time Frequency Standard, I’m betting manfactured by Datum, complete with a Cesium Beam Tube – It looks like an old Model FTS-7103 for the tube.

  6. Serious says:

    Time-travel machine? ;-)

  7. Jesse says:

    Bunnie, you hyperlinked the pic wrong. The larger version (for everyone else) is at

  8. KE5FX says:

    I was actually going to buy a better camera to take a larger photo, but dragged my feet too long. I thought he was going to post it *next* month. :) I even set the BCD switches to 481516 in preparation for the reshoot.

    So the good news, Bunnie just saved me about $500. Which coincidentally is what this thing cost in the first place.

    //lots of interesting guesses, but nobody’s nailed it yet

  9. I think its a satellite radio or modem..

  10. oPossum says:

    GPS Satellite

  11. Brian says:

    The millisecond delay range on the thumbwheel suggests a
    time code generator/modulator for LORAN-C, IRIG, or somesuch.

    The set /hold buttons remind me of (non-cesium) timecode
    generators I’ve used in years past.

    Bottom half looks to be a cesium tube and physics package.

    Synthesizer and OCXO in the top half.

    Time delay, modulator(?), output amp in the middle.


  12. gregh3285 says:

    This is a microwave transmitter used in the Federal Telecommunication System, a separate phone system operated by the US government. The bottom sub-assembly, manufactured by Datum, is an electron tube. The unit was used at one of the switching centers.

  13. Brian says:

    Earlier, I posted:
    >The millisecond delay range on the thumbwheel suggests a
    >time code generator/modulator for LORAN-C, IRIG, or somesuch.

    On second thought, the 1985 HP catalog lists a 1 pps adjustment
    range of one second for the 5061A, so that delay adjustment
    thumbwheel looks to be part of the usual stuff in an HP 5061A

    My 1989 HP catalog gives the following cesium model timeline:

    1964 HP 5060A
    1967 HP 5061A
    1973 HP 5061A High Performance Beam option
    1986 HP 5061B

    Since John’s post ruled out MegabytePhreak’s call of a 5061B,
    that leaves the other models to look at.

    HP 5060A internals:

    Similar construction style, but a much diferent layout.

    Searching for different versions of the 5061 finds:

    1968 5061A Service Manual

    Figure 3-5, page 3-10 is very close, with BCD thumbwheels on the
    synthesizer, a different OCXO section, differences in clock set
    buttons function & location, and in the oven controller.

    1978 5061A Service Manual
    ***Caution: 25 MB FILE LINK***

    Figure 3-2, Page 3-3 of this 1978 5061A maintenance manual is
    a near match, differs in the oven and OCXO area.

    The clock set button location and functions are identical.

    1986 5061B Service Manual

    Figure 3-2, page 3-3 of this 1986 5061B maintenance manual is close;
    different BCD switch orientation, different clock switch functions.

    But the oven controller and OCXO on this one are a match…

    … So I’ll go with “mid-life production 5061A with a Datum replacement tube”


  14. charlieh0tel says:

    It is an HP 5061B with a replacement CBT by Datum.

    I have one that is the same (i.e. original CBT replaced with a Datum CBT).

  15. Interesting collection of time standards:

  16. satellite radio is cool coz you can have a signal anywhere*,-