I ordered a 10 Mhz Reference (GPS Stabilised 10 MHz Oscillator)

My plan is to use it for my Radios and for my Test bench

I'm leaning towards just buying a couple od 10-4 Distribution Amps
from Down Easy Microwave since they can be daisy chained.

I'm curious as to what others are using for a distribution amplifier.

Do I need the outputs to be Galvanically isolated?


Thank you

I looked for an amplifier / active splitter and never found a good one that was reasonably priced.  I did the math on my Trimble Thunderbolt's output, the loss through a passive splitter, and the signal requirements of my gear, and everything was in spec so I went with a passive splitter and it works great.  The Thunderbolt is feeding My Flex 5000, a HP spectrum analyzer, HP frequency counter, and two Fluke signal generators.  I can't feed anything else but what I have works great.

I'd be interested if you find something good so I can have a signal available for other stuff if needed.

Tag for more info, because I have no idea what you're talking about, Mr. Harry!  

10MHz Amplified and Filtered 4 Way divider Complete kit with enclosure.

$50 as a kit from Down East Microwave Here

Thanks, Mr_Harry!  Sorry to say my mind is going though, because I just noticed that I downloaded that PDF on June 10th of this year.    Al least I have the joy of discovering it twice now!  

Basically I have a a very accurate 10 MHz oscillator that I connect to
the reference in put on all my gear it makes the frequency dead on.

I use receive converters and transverters and each has it's on local reference oscillator.
(that in turn can lead to frequency errors as the crystal in the oscillators age requiring them
to be re-calibrated) this basically tells them all to use the same very accurate reference
oscillator eliminating any frequency errors between them and the need to re calibrate them.

It is a Nice to have thing so you know you are dead on to to something like 12 decal places

example 10.000000000000 MHz

I talked to him and he said they can be daisy chained as many as you like since they are pretty much unity gain

To add to Mr_Harry's excellent description, there are a couple of programs that let you monitor your reference.  A GPSDO is a Global Positioning System Disciplined Oscillator.  Lady Heather is one of those programs and it's amazing to watch the way it all works with the GPS satellites and all the technical details.  Bad oscillators can be disciplined just like bad people, which is why Lady Heather wears leather and carries a tool of discipline.  



Interested now, BigDaddy?  

I'm headed to the rack.  Be right back.  

ETA:  Thanks for the breakdown Mr. Harry and KwaiChangCaine.

if the passive approach works, use it.  quality 2 way and 3 way splitters suitable for use at 10MHz are available from mini-circuits and others.

if a passive approach doesn't work, there are generally two options:

1) daisy chain the instruments.  

high end scopes and the like (such as you list above) have a REF IN and a REF OUT bnc.  if the signal at REF IN is valid, REF OUT will be a buffered copy.  this way you can take a single 10MHz reference signal, connect it to the REF IN on the HP SA, then use the REF OUT to HP counter REF IN, and so on.  in general the REF OUT bnc on HP/Agilent gear provides a good enough copy for 99.9999% of typical benchtop use.   (where we don't use this approach in our performance lab is with network jitter/wander testing used for formal equipment certification tests; here the 10MHz feed from a cesium reference ("atomic") clock is applied directly at the test instrument without intervening buffers/amplifiers of any type.)

2) use a distribution amplifier.

in theory, a good reference frequency distribution amp will have a gain of 0db at 10MHz (or perhaps +1dB to help with cable losses), will not add jitter or spurious noise (sidebands) to the outputs, and will also provide infinite input-to-output and output-to-output isolation so noise introduced anywhere does not propagate through the system.   in practice, though, all amplifiers (even unity gain) contribute phase noise and spurious noise, and in addition have finite isolation characteristics.  herein lies the rub: it is essential that you understand that active components do "things" to a signal which you are expecting to be a reference (that is, very high accuracy, and very low jitter (=phase noise), wander, and drift).  whether or not the degradation introduced by the distribution amp is detrimental to your application is completely under your purview and related to what you are trying to accomplish.  

for most amateur radio applications, inexpensive distribution amps will provide excellent results.  for the most part, the parameters i would most be interested in knowing from an amp vendor are phase noise (this will show up in SSB and FM if it is bad enough) and output-to-output isolation (one of the "distribution clients" can pull the other clients around, or pollute their references).  unfortunately, minimizing phase noise and maximizing output-to-output isolation is hard to design and expensive to build.  

just as an academic side note, the specifications of laboratory reference distribution amps from Symmetricon (recently purchased by Microsemi) are linked below.  none of the Symmetricon hardware is in the realm of affordability for typical amateur radio use -- however it is useful to compare specifications with low cost or DIY kit distribution amps.

http://www.microsemi.com/products/timing-synchronization-systems/time-frequency-distribution/1u-distribution-amplifiers
PDF spec sheets:
http://www.microsemi.com/document-portal/doc_download/133406-6502b
http://www.microsemi.com/document-portal/doc_download/133413-4036b

one final note:
you can do yourself a big favor by terminating (with 50ohms) the unused outputs on any distribution amp.  this prevents internal reflections on the amplifier and generally results in quieter reference outputs.  BNC's with integral 50 ohm terminations are cheap and effective.

ar-jedi

One correction, I used the word "bad", and I think the correct term would be "naughty".  She tried to teach me that but I never caught on, maybe that's part of the reason things didn't work out...  

here is how a GPSDO works:
http://www.ar15.com/forums/t_10_22/633716__ARCHIVED_THREAD____It_s_about_Time___NIST_WWV_Radio_Reference_Signals.html&page=1#i10797506

see also
http://www.ar15.com/forums/t_10_22/673288__ARCHIVED_THREAD____I_want_a_10_MHz_Standard.html&page=1#i11515439

reminder:
just, whatever you do, DO NOT PURCHASE A SECOND REFERENCE SOURCE.

a few months later, and a lot of sleepless nights, you'll be sorry you did.  

i am telling you this from experience.  

ar-jedi

ETA

here is the post i was REALLY looking for:
http://www.ar15.com/forums/t_10_22/665017__ARCHIVED_THREAD____can_I_make_my_PLL_reference_oscillator_less_temp_sensitive_.html&page=1#i11362542

ps
just as an example:
http://fwfvq.tehfm.servertrust.com/product-p/10-4ck.htm --> http://fwfvq.tehfm.servertrust.com/v/PDF/10-4pd.pdf


http://www.microsemi.com/products/timing-synchronization-systems/time-frequency-distribution/1u-distribution-amplifiers/6502b#overview --> http://www.microsemi.com/document-portal/doc_download/133406-6502b


ar-jedi

The man with one clock always knows what time it is.  

Thank you all for the info


Now all I need is more time

sir, do you have the time now?


ps
... and how are you distributing your 10MHz ref?

ar-jedi  

Waiting on Mr_Harry's answer since I blame this on him.  

The passive one under my desk that works fine:



The active one I that I've always wanted and bought because of this thread (Serial number 223):

Sorry for the Delay in answering....  I've only slept 2 hrs in the past 36.... Oh is this going to be a nice paycheck



I went with 2 of the DEMI 10-4 Distribution amps (Kits)

Beat by 3 weeks, never mind.