[time-nuts] Antenna for T-bolt

[cfo]

On Mon, 02 Apr 2012 15:28:40 -0700, Bob Martin wrote:

> Bill--
> 
> The Thunderbolt wants a higher gain antenna than most standard GPS
> receivers.  I tried standard Garmin active antennas, and while they
> worked (I have a good view of the sky), signal levels could be better.
> 
> Best match probably is something like the HP/Symmetricom 58532A antenna,
> which has gain > 30dB -- most "active" GPS antennas are in the 24 - 26
> dB range.
> 
> They're not cheap, but they'll do the job.
> 
> If you have much distance to cover, feed line is of course important as
> well -- 9913, LMR 400, good quality RG6, something with low loss at 1.5
> GHz.
> 
> I'm using a 58532A feeding a Symmetricom 58535A active GPS splitter to
> run a Thunderbolt and a Datum Tymserve 2100.  Feedline is 9913 to the
> splitter, and short LMR 195 SMA cables from there.  (Yes you can find F
> to SMA adapters, on eBay, even though many will shudder at the
> concept...)
> 
> 73 Bob K6RTM
> 
> 
> 
> On Apr 2, 2012, at 15:01, time-nuts-request at febo.com
> wrote:
> 
>> ------------------------------
>> 
>> Message: 4
>> Date: Mon, 2 Apr 2012 17:39:40 -0400
>> From: "Bill Riches"
>> <bill.riches at verizon.net> To: "'Discussion
>> of precise time and frequency measurement'"
>> 	<time-nuts at febo.com>
>> Subject: [time-nuts] Antenna for t-bolt Message-ID:
>> <01ac01cd1119$1c699af0$553cd0d0$@riches-H
+0wwilmMs3R7s880joybQ at public.gmane.org>
>> Content-Type: text/plain;	charset="US-ASCII"
>> 
>> Hi guys,
>> 
>> I have asked this question several times over the past few weeks and
>> get no answer.  Have I been ostracized??!!
>> 
>> Question is that I am looking for suggestions for GPS antenna for
>> t-bolt. The antenna that I am using now is a no name and I not know
>> where it came from!  Wonder if a Garman GA-30 will work?
>> 

I think "any" 5v antenna with a 25+ dB gain would work.
But the Tbolt likes a high gain antenna.

I'm using Maxrad GPS-TMG-40 (40dB) with N-Conn , in Copenhagen.
It works reasonably fine with 25m quality 75ohm cable.
It's on the balcony , with an ok view to the south.
But absolutely no view north , so a bit of the time only 2 sats active.
LH says 
adev 1.2x e-12 on PPS
adev 5.3x e-13 on OSC

In my summerhouse i use the "mushroom like" antenna that came with the 
kit from fluke.l , but i have an extra Maxrad waiting to be mounted.


This might be a good choice "eby item : 320881667391".
Just key in the # in search

This is the symetricom as item : 300571554900


cfo