Empathy List Archives

FH

Frank Hughes

Sat, Aug 18, 2012 1:12 AM

Hi,
New guy here, seeking Oracular pronouncements for my time/frequency quest!

I recently acquired an HP 3336B, and subsequently converted it to a "C" model,
as all the HAM and related equipment here is 50 ohms.

The 3336 has "Option 004: High stability frequency reference".
Operates at about 6Mhz....

I am trying to decide whether to fix the 3336 ocxo, or just use the other working
ocxo in the Agilent E8285A Spectrum Analyzer.
OR
It would really be fun to provision some type of Primary Reference and accurate 10Mhz source, and distribute the signal.

I found a bunch of them on ebay, but they are almost all in China....what is going on here?

Anyone ever had a good buying experience for this type of equipent from China?

While decending through this particular worm-hole, I realized that it would be great to have
my own NTP server via GPS too.
Found a bunch of GPS receivers w/ Ethernet and NTP server features, but none w/ ocxo, only vcxo and tcxo.
Possibly it does not matter if the reference is the Stratum-1 GPS?
Not sure what I am looking at here (obviously)

I only know a little about these topics, as where I work we have an Agilent_5071A, paired with a
Symmetricom GPS PRS system.
But as we have moved out of the old TDM and ATM technologies, we no longer need a Stratum-1 source,
(and the 5071A has used up all it's Cesium anyway). But it was fun and I learned many things.

So what I am trying to come up with now for home/shack is:

An NTP server for our LAN
A very high quality 10Mhz source to distribute to all the HP and Agilent equipment here.

I have read enough forums to become dizzy, and would be glad to buy an HP Z3815A, or
an HP Z3816A or an HP Z3801A or...
I even found an HP 55300A, but w/o the shelf it is useless,
(100 edge connector pinouts to decipher and wire manually???)

Advice much appreciated!
73
Frank
KJ4OLL

Hi, New guy here, seeking Oracular pronouncements for my time/frequency quest! I recently acquired an HP 3336B, and subsequently converted it to a "C" model, as all the HAM and related equipment here is 50 ohms. The 3336 has "Option 004: High stability frequency reference". Operates at about 6Mhz.... I am trying to decide whether to fix the 3336 ocxo, or just use the other working ocxo in the Agilent E8285A Spectrum Analyzer. OR It would really be fun to provision some type of Primary Reference and accurate 10Mhz source, and distribute the signal. I found a bunch of them on ebay, but they are almost all in China....what is going on here? Anyone ever had a good buying experience for this type of equipent from China? While decending through this particular worm-hole, I realized that it would be great to have my own NTP server via GPS too. Found a bunch of GPS receivers w/ Ethernet and NTP server features, but none w/ ocxo, only vcxo and tcxo. Possibly it does not matter if the reference is the Stratum-1 GPS? Not sure what I am looking at here (obviously) I only know a little about these topics, as where I work we have an Agilent_5071A, paired with a Symmetricom GPS PRS system. But as we have moved out of the old TDM and ATM technologies, we no longer need a Stratum-1 source, (and the 5071A has used up all it's Cesium anyway). But it was fun and I learned many things. So what I am trying to come up with now for home/shack is: - An NTP server for our LAN - A very high quality 10Mhz source to distribute to all the HP and Agilent equipment here. I have read enough forums to become dizzy, and would be glad to buy an HP Z3815A, or an HP Z3816A or an HP Z3801A or... I even found an HP 55300A, but w/o the shelf it is useless, (100 edge connector pinouts to decipher and wire manually???) Advice much appreciated! 73 Frank KJ4OLL

CA

Chris Albertson

Sat, Aug 18, 2012 2:32 AM

On Fri, Aug 17, 2012 at 6:12 PM, Frank Hughes hp_ciscovss@yahoo.com wrote:

So what I am trying to come up with now for home/shack is:

An NTP server for our LAN
A very high quality 10Mhz source to distribute to all the HP and Agilent equipment here.

Here is what I would do again,...

first get the NTP server running but use pool servers from the
Internet as the reference clocks. Get this working well before you
attempt to set up a GPS. But when you choose a computer make sure
that it has an RS-232 serial port. Accuracy is more then an order of
magnitude better then a USB hookup. It fack USB is so poor you can't
take full advantage of GPS. I use an Intel Atom board. I got the
one that uses a pasive heat sink and it only burns a very few watts.
This matters becaue it runs 24x7. A big PC can cost $40 a month to
run. The best OS to use is either BSD or Linux. These have order of
magnitude better performance than others for this purpose
Find a place for a GPS antenna. It should be able to see to the
horizon all 360 degrees. Well if you live in the USA some blockage to
the North is OK. Put it on a short mast and as a ham you know about
lightening and grounding and so on.. Don't skimp on that. 3/4 iron
plumbing pipe with a pipe flange on top makes a perfect mast and you
can run the cable down the pipe. Getting a good view of the entire
sky helps a lot. Although it can work even just looking out a
window. The 75 ohm double sheiled cable TV coax works well and is
cheap.
Buy a Trimble Thunderbolt GPS from eBay. These are the best and
easy to use and cost maybe $125. They produce a very good 10MHz
output from an internal OCXO. They also have a one pulse per second
output and of course serial rs-232
Finally connect Thunderbolt's PPS and serial data to the computer
and edit the NTP config file to add the GPS. Keep the Internet pool
servers.

Chris Albertson
Redondo Beach, California

On Fri, Aug 17, 2012 at 6:12 PM, Frank Hughes <hp_ciscovss@yahoo.com> wrote: > So what I am trying to come up with now for home/shack is: > - An NTP server for our LAN > - A very high quality 10Mhz source to distribute to all the HP and Agilent equipment here. Here is what I would do again,... 1) first get the NTP server running but use pool servers from the Internet as the reference clocks. Get this working well before you attempt to set up a GPS. But when you choose a computer make sure that it has an RS-232 serial port. Accuracy is more then an order of magnitude better then a USB hookup. It fack USB is so poor you can't take full advantage of GPS. I use an Intel Atom board. I got the one that uses a pasive heat sink and it only burns a very few watts. This matters becaue it runs 24x7. A big PC can cost $40 a month to run. The best OS to use is either BSD or Linux. These have order of magnitude better performance than others for this purpose 2) Find a place for a GPS antenna. It should be able to see to the horizon all 360 degrees. Well if you live in the USA some blockage to the North is OK. Put it on a short mast and as a ham you know about lightening and grounding and so on.. Don't skimp on that. 3/4 iron plumbing pipe with a pipe flange on top makes a perfect mast and you can run the cable down the pipe. Getting a good view of the entire sky helps a lot. Although it can work even just looking out a window. The 75 ohm double sheiled cable TV coax works well and is cheap. 3) Buy a Trimble Thunderbolt GPS from eBay. These are the best and easy to use and cost maybe $125. They produce a very good 10MHz output from an internal OCXO. They also have a one pulse per second output and of course serial rs-232 4) Finally connect Thunderbolt's PPS and serial data to the computer and edit the NTP config file to add the GPS. Keep the Internet pool servers. Chris Albertson Redondo Beach, California

BD

Bill Dailey

Sat, Aug 18, 2012 2:35 AM

On a budget get a thunderbolt... If you want plug and play get a Jackson labs Fury. I have my fury hooked up to small Ubuntu box and have a nice ntp server as well as a great reference. Also, read, read, and read some more.

Doc
KX0O

Sent from my iPad

On Aug 17, 2012, at 8:12 PM, Frank Hughes hp_ciscovss@yahoo.com wrote: