[time-nuts] STUPID QUESTION: Lucent KS-24361, HP/Symmetricom Z3809A, Z3810A, Z3811A, Z3812

Anthony Roby aroby at antamy.com
Tue Nov 18 11:49:52 EST 2014


If you search through the recent messages, you'll see a link to a set of photos I posted.  This one https://drive.google.com/file/d/0B5tlecUITRBLc3JyMElTdUwzMHM shows the front of the units. J7 provides the GPS power.

Anthony

-----Original Message-----
From: time-nuts [mailto:time-nuts-bounces at febo.com] On Behalf Of Don Murray via time-nuts
Sent: Tuesday, November 18, 2014 10:30 AM
To: time-nuts at febo.com
Subject: [time-nuts] STUPID QUESTION: Lucent KS-24361, HP/Symmetricom Z3809A, Z3810A, Z3811A, Z3812

Hello all...
 
Just getting up to speed on the KS-24361...
 
My stupid question (s)...
 
Where does the GPS antenna connect??
 
Does the GPS antenna port power the antenna?
 
Need a replacement for my dead HP Z3816A...   ;-(
 
TIA...
 
 
 
73
Don
W4WJ 

 
 
In a message dated 11/18/2014 3:26:52 A.M. Central Standard Time, mark at alignedsolutions.com writes:

One of  my Z3805's (with the double oven 10811 ocxo iirc) also performs 
similarly at  times to the 58503A mentioned by Said.   From an adev perspective 
 it's close to my BVA at some tau's (around a hundred seconds or so  iirc.) 
 At times though the output seems to "jump" in  frequency.   My other Z3805 
from the same source doesn't work as  well.

None of the 10811's in my various pieces of test gear (some of  which I basically purchased to get the 10811's) worked all that well from an  Adev perspective.  I used to buy HP5328 counters on the usual auction  site with 
10811's and the 500MHz C channel for quite low prices.     At least I still have 
a nice collection of frequency counters.


Sent  from my iPad

On 2014-11-17, at 1:23 PM, Said Jackson via time-nuts  <time-nuts at febo.com>
wrote:

> Correct on all counts  Bob.
> 
> My two 58503A units from China are great for both ADEV  and PN
measurements, better than anything else I have as a combo (I have  Wenzel ULNs for even lower PN testing but they don't have any usable  ADEV).  I also have a costly BVA and it can't compete against the HP  unit.
> 
> Those 10811s just rule.
> 
> In fact my  only complaint about the 58503A are the 60Hz related small
spurs you can see  in the plots...
> 
> Bye,
> Said
> 
> Sent From  iPhone
> 
>> On Nov 17, 2014, at 12:28, Bob Camp  <kb8tq at n1k.org> wrote:
>> 
>> Hi
>>  
>> The 58503 is a Z3801 with a pretty instrument style package put  
>> around
it - right?
>> 
>> If so, it might / should   have a 10811 in it rather than an MTI OCXO. 
The 10811 is rated for -155 dbc at  100 Hz. That is much better than the noise floor that the MTI ??s seem to  produce at 100 Hz. About the only other GPSDO OCXO that gets to that level is  the one in the original TBolts . There you very much have to deal with spurs.  That make the noise floor of limited use in a practical system. 
>>  
>> Bob
>> 
>>> On Nov 17, 2014, at 2:26 PM,  SAIDJACK at aol.com wrote:
>>> 
>>> Hi  Bob,
>>> 
>>> yes, the 10MHz plot is rotten, no doubt.  The 15MHz plot is quite 
>>> good
till about 40Hz offset, then it becomes pretty  rotten too.
>>> 
>>> Here is one of my 58503A units  (using the 10811 OCXO) as a
comparison.. measured against our DROR-IIA (this  plot was actually done to show the DROR-IIA PN, but since that unit actually  has less noise and spurs than the 58503A we can simply use it as the reference  for this purpose).
>>> 
>>> The good news is that  getting the close-in phase noise to be good 
>>> is
very hard to do and the unit  delivers that out-of-the box already. Filtering out the noise and spurs above  40Hz offset is pretty easy to do. It should be fairly straight forward to  cobble up a small PN filter for those units to get rid of the noise and spurs  above 40Hz offset.
>>> 
>>> bye,
>>>  Said
>>> 
>>> In a message dated 11/17/2014 09:31:46  Pacific Standard Time,
kb8tq at n1k.org writes:
>>>  Hi
>>> 
>>> Here ??s the phase noise on the 15 MHz.  There are a few spurs, and 
>>> an
very real hump out at the likely frequency of  the Lucent switcher.  The 15 MHz is pretty clean compared to most /all of  the other units I ??ve seen on the surplus market. 
>>>  
>>> I would not multiply this up to 40 GHz with a broadband  multiplier. 
>>> I
would be quite happy to run it into a PLL with a rational  bandwidth. You will beat the noise on the output with a fairly simple VHF VCXO  past 100 Hz. 
No reason to have a bandwidth outside the 20 to 80 Hz range.  
>>> 
>>> Math:
>>> 
>>> 15  MHz to 150 MHz -> 20 log (N) -> 20 db.
>>> 
>>>  -140 dbc / Hz shown below at 100 Hz offset -> -120 dbc/Hz
>>>  
>>> You can get numbers better than -120 dbc/Hz at 100 Hz offset  out of 
>>> a
number of pretty simple VHF VCXO circuits. Bert has one that seems to  work fine for him. 
>>> 
>>> Bob
>>>  
>>> <DROR-IIA_Phase_Noise.png>
>> 
>  _______________________________________________
> time-nuts mailing list  -- time-nuts at febo.com To unsubscribe, go to
https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> and follow the  instructions there.
>  

_______________________________________________
time-nuts mailing  list -- time-nuts at febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the  instructions there.
_______________________________________________
time-nuts mailing list -- time-nuts at febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.


More information about the time-nuts mailing list