Hi Ignacio,

I got one of these units, from the same seller (actually it is the one
which is pictured). It had a broken connector and a dent in the cylinder
casing.

Luckily the unit powers up! And it generates the frequencies it should
generate.

But: the frequency tuning is a bit stiff/non-responsive and the tape
which is used in the oven is a bit old. Fixing this unit seems like a
nice winter-project ;-)

Is there anyone on the list who knows where to find the Sulzer manuals
(preferably as PDF)? As it is basically a Sulzer 2.5 / Sulzer 5.0.

Thank you, best regards, Jeroen

On 09/12/2012 01:28 AM, EB4APL wrote:

This unit on ebay is made from Racal. The complete unit, oscillator and
power supply is the MA259. It is a +/- 5 e-10 day stablity.

This equipment is only good to spend winter time or for museum. Several
newer oscillator,like HP10811/10544, have the same characteristics or
better in smaller size.
The component used ar not the best and you can have fault expecially on
the power supply.

I have a paper copy of the manual also for the Sulzer 5A (AN/URQ10).

Luciano
www.timeok@timeok.it
IZ5JHJ

Il 2012-09-13 15:31 Jeroen Bastemeijer ha scritto:

--
timeok

Luciano,

My experience is that some of these old 2.5 or 5 MHz Sulzer oscillators have vastly better performance than most 10811/10544. For example, see:
http://www.febo.com/pages/oscillators/sulzer/
http://leapsecond.com/museum/sul25-1/
http://leapsecond.com/museum/sul25-2/

While it is true that they don't always work out-of-the-box when you find them cheap on eBay, once fixed, their performance is stunning. That's why these rare old Sulzer's are highly prized.

/tvb

Yes Tom you right,
but your example is on a rare Sulzer 2.5 MHz. Another very good
reference can be an HP 106 (quasi impossible to find). This is not valid
for the Racal model as described. I have had several unit of this
standar under test and I keep one for my personal small museum. I have
also a Suzer 5 MHz, it is better than Racal but same as performance to
several others. I have an HP 107Br but it is not working and I cannot
test it at the moment.

All us are looking to find some units in flea market, old and good, but
this is a very rare event due the fact there is a large 5e-10
(OCXO)production or lower, and few top performance  products as you
describe.

good luck to us!

Luciano

Il 2012-09-14 19:32 Tom Van Baak ha scritto:

--
timeok

Welcome aboard,
there are terms that are simple to explain, the others require a more
extended study. For example, the PRN is the GPS satellite identification
number, nothing more to be said. Yes, you can then learn more but complete
meaning is that. The term ADEV requires a more extended attention than
saying: it is a measure of the oscillator stability. There are tons of
papers on the ADEV (Allan deviation), just google for it and you can really
learn a lot of things.

On Mon, Sep 17, 2012 at 5:27 PM, George Race george@mrrace.com wrote:

Dear Tom, Luciano, all,

Thank you for your comments. The Sulzer is not intended to be used as a
high accuracy standard. The oscillator fits nicely to some old radio's
;-) However, I think (not measured) that stability of the oscillator is
better then the average stability of a modern low budget oscillator.

Therefore it would be nice to have it up and running. The schematic on
the website of  Tom was very helpful. Basically it would be sufficient
for trouble-shooting/repair. However, I would like to figure out the
numbers which should be indicated by the moving coil meter on the front.

I did a quick measurement with a HP counter 53230A (without a very
stable reference). The number shown for the allen variation (after a
couple of hours) was 1.5mHz on the 5MHz signal. (Maybe this number shows
the stability of the HP....??) This number gives good hope, according to me.

Is there a source for manuals on these instruments? I checked the site
of KO4BB, unfortunately he doesn't have a PDF of the manual.

Best regards, Jeroen

On 09/17/2012 02:50 PM, Timeok wrote:

Hi Jeroen,

I have a paper copy of the SULZER 5A (the 5 MHz version) and of the
Racal. If you want I can make a paper copy and send you it by postal
service. I do not know if Tom have a pdf copy of the manuals. Me too
have these OCXO for passion. I suggest you to buy e ceep GPSDO and use
it as reference for your counter, so you can start to do accurate
measurement and compare the standard you have (or will have) in your
lab.

Let me know, for logistic use my direct email:  timeok@timeok.it

Luciano
IZ5JHJ
www.timeok.it

Il 2012-09-18 09:04 Jeroen Bastemeijer ha scritto:

--
timeok

Dear Luciano,

Thank you for your offer to make copies of the manuals. If it is OK with
you, I can make a PDF-scan of the manuals and send them to KO4BB to be
put on his website. I will contact you offlist for my address details.

Luckily enough I have a GPSDO, but... the GPSDO is at home and the
counter is at work. A challenge to get these two together ;-)

Best regards, Jeroen PE1RGE

On 09/18/2012 10:30 AM, Timeok wrote: