[time-nuts] Anyone have a comparison of the Z3805A and a Tbolt?
lists at rtty.us
Tue Sep 7 16:42:55 UTC 2010
The "China" 3805's run on 48 volts and are internally marked Symmetricom and
marked Samsung on the outside. The cheaper "Korea" 3805's run on 24 volts
and are marked HP internally. There is about a 5 year difference in age
between the HP and the Symmetricom units.
From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On
Behalf Of Rex
Sent: Tuesday, September 07, 2010 11:56 AM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Anyone have a comparison of the Z3805A and a Tbolt?
I wonder if you are really talking about Z3805A's?
I know the double-oven version of 10811's were in the earlier Z3801A's;
never heard of one in Z3805A. I have a Z3816A and a Z3805A. They both
have MTI 260-model 5 MHz oscillators. I assume that is the "better" one
you are referring to. My Z3805A is marked Samsung, as are all the ones I
see coming from China.
The current price seems to be more like $350 than $250 for the ones
left. I think $350 is about what I paid for my Z3805A a bit over a year,
or so, back.
On 9/7/2010 4:34 AM, Bob Camp wrote:
> The "bad units" with the 10811's in them are usually marked "HP". The
> "good units" with the true DOCXO in them are normally marked
> From: "Pete Lancashire" <xyzzypdx at gmail.com>
> Sent: Monday, September 06, 2010 6:14 PM
> To: "Discussion of precise time and frequency measurement"
> <time-nuts at febo.com>
> Subject: Re: [time-nuts] Anyone have a comparison of the Z3805A and a
>> Is there an external way on the 3805's to id the desired 10811 ? S/N
>> or ?
>> Ditto on the 10811's
>> On Mon, Sep 6, 2010 at 11:31 AM, Bob Camp <lists at rtty.us> wrote:
>>> I have a couple 3805's and more than a couple TBolts.
>>> There are two 3805's, one has the double heated 10811 the other has
>>> a true
>>> double oven. The true double oven / later design is the one you want.
>>> Typically they have better TC and better ADEV at 10 seconds compared
>>> to the
>>> earlier part.
>>> The TBolt has a much better GPS receiver in it and it is far more tweak
>>> able with the Lady Heather software. It's default settings are not
>>> as good
>>> as the defaults on the 3805. With some work they can be vastly
>>> The 3805 runs on a single 24 or 48 volt supply depending on the
>>> model you
>>> get. The TBolt needs +12, +5 and -12. Battery backup is easier on
>>> the 3805.
>>> TBolts run $75 +/- 25. 3805's run $250 +/- $50. Shipping will be a
>>> bit more
>>> on the 3805.
>>> The TBolt wins in bang for the buck and fun to tweak categories. The
>>> is the better plug it in and ignore it forever box.
>>> Both will track a cesium well at 100,000 seconds and beyond. Both
>>> look a
>>> lot like GPS at 100 seconds or so. Both have some significant
>>> variation unit
>>> to unit.
>>> On Sep 6, 2010, at 11:13 AM, swingbyte <swingbyte at exemail.com.au>
>>> > Hi All,
>>> > Have been thinking of getting a GPSODO and I'm looking for advice
>>> on > what
>>> to choose. I haven't been able to find an ADEV comparison between
>>> these two
>>> units and am curious to know how their differences manifest themselves.
>>> Apart from the 12 satelites vs 8 what practical advantages are
>>> there in the
>>> 3805A over the Tbolt? With all the extra components there has to be
>>> something. I notice that the ocxo is not the large Docxo of the
>>> 3801A -
>>> which is better?
>>> > Thanks
>>> > Tim
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