No subject


Mon Dec 13 16:21:17 UTC 2010


could put a QFP or two on boards for those less sure of their talents.
That makes doing a run of a dozen or two of anything non bga wouldn't
be an issue. As Xtof pointed out, a controller (or a good eye) and an
old toaster oven can go a very long way. There are also 'breakout
boards' available for most QFPs that might make such a project easier.

The discussion has had me dig out the t'bolt, a few counters and a few
m of coax to do the old 'speed of light' demo. Now I want a newer,
better counter! :)

I have a stash of ~25 ATMega128's and the programmer I'd be willing to
toss at the project for example. Time, on the other hand could be
slightly harder to come by.

Bob


On Thu, Dec 16, 2010 at 3:55 PM, Bob Camp <lists at rtty.us> wrote:
> Hi
>
> If you look in detail at the ups and downs of the TAPR SDR project, it's =
not
> one I would want to emulate.
>
> If we have a few hundred people interested with cash in hand, this might
> indeed make sense.
>
> Bob
>
> -----Original Message-----
> From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On
> Behalf Of Chris Albertson
> Sent: Thursday, December 16, 2010 3:36 PM
> To: Discussion of precise time and frequency measurement
> Subject: Re: [time-nuts] Frequency counter recommendation
>
> Here is an example of doing something like this as a open source
> design by a group of HAMs
> http://www.tapr.org/kits_janus.html
> This is a software defined radio but is close to the complexity we are
> talking about here. It has a d/a converter and fpga and lots of
> surface mount parts. =A0TAPR is able to have these made and sell them
> for $180.
>
> While this is a proof by example that such a project can be done I'd
> not go this route. =A0 =A0 Better I think to design a modular system wher=
e
> the modules =A0have easy and well defined interfaces and where each =A0ca=
n
> have whatever quality specs are desired. =A0 There is a danger with
> these group project that you run into a requirements "race" to the top
> and end up with a hard to manufacture and maintain part. =A0I think the
> HPSDR project did this
>
> On Thu, Dec 16, 2010 at 11:20 AM, Bob Camp <lists at rtty.us> wrote:
>> Hi
>>
>> Yes indeed, been there done that. Not very hard at all.
>>
>> All you need is the six layer pc board (can be bought), the FPGA (Digike=
y
>> has them), a few of these and a couple of those. Spend less than $100 an=
d
>> you are in business if the PC board volume is high enough.
>>
>> In this case the next step in the business is to solder the 256 ball 1 m=
m
>> spacing BGA package down on the pc board. Not so easy without the right
>> tools...
>>
>> Bob
>>
>> -----Original Message-----
>> From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On
>> Behalf Of Don Latham
>> Sent: Wednesday, December 15, 2010 3:48 PM
>> To: Discussion of precise time and frequency measurement
>> Subject: Re: [time-nuts] Frequency counter recommendation
>>
>> OK, time-nuts, here's the gauntlet. can't "we" generate a design for a
>> PC-based FPGA or chip setup that would be generally useful as a counter?
>> We've seen thorough discussions about trigger jitter, which IMHO is the
>> fundamental problem. And isn't the PIC2 Time base from 10 MHz standard,
>> all else should be straightforward.
>> I'm not a designer, just a messer-arounder, or I'd give it a shot. Robot
>> Basic is a nice PC software maybe.
>> Don
>>
>> J. L. Trantham, M. D.
>>> I suspect that this question will lead to a discussion of Dual Mixers b=
ut
>>> as
>>> far as the counter question goes, I would recommend you consider an HP
>>> 5370B.
>>>
>>> Joe
>>>
>>> -----Original Message-----
>>> From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com]On
>>> Behalf Of Dave M
>>> Sent: Wednesday, December 15, 2010 1:55 PM
>>> To: TimeNuts
>>> Subject: [time-nuts] Frequency counter recommendation
>>>
>>> I'm a retired electronics tech and computer programmer. =A0I have a pre=
tty
>>> decently equipped shop for almost all of my projects and experiments.
>>> However, my time and frequency equipment is a bit long in the tooth. =
=A0I
>>> have
>>> a couple old HP 5328A counters (commercial version; not the military
>>> version), one with a 10544, the other with a 10811 oscillator.
>>> I have an HP Z3801A that has been operating well for several years, and
>>> recently acquired a TBolt to keep the counters in tune. =A0I also have =
a
>>> good
>>> distribution amp and =A0couple of old Montronics (Fluke) frequency
>>> comparators.
>>> What I'm looking for now, is a recommendation for a good low-cost (<$40=
0)
>>> counter that will get me on the way to performing some of the "down in
> the
>>> grass" noise, jitter and deviation tests that the more learned members =
of
>>> the group discuss. =A0I know that new equipment is far out of my budget=
,
> but
>>> I'm also aware that some of the older, now obsolete (also cheaper)
>>> equipment
>>> is quite capable of doing what I want to do. I prefer HP equipment sinc=
e
>>> manuals are much easier to find than most other brands.
>>> I'd also like recommendation for a good low-cost GPIB controller that
>>> allows
>>> me to write software to control some of my instruments. =A0I have
> experience
>>> writing software in BASIC on a Fluke 1722A controller. =A0I've seen the=
se
>>> controllers on the Bay and other online vendors, but I've not located t=
he
>>> BASIC discs for them. =A0Any advice?
>>> I realize that a counter is not the only piece that I need, but it's
> first
>>> on my list. =A0Other, more applicable equipment is on my want list, but
> will
>>> have to wait for a bit.
>>>
>>> Thanks for advice,
>>> David
>>> dgminala at mediacombb dot net
>>>
>>> _______________________________________________
>>> 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.
>>> -----
>>> No virus found in this message.
>>> Checked by AVG - www.avg.com
>>> Version: 10.0.1170 / Virus Database: 426/3317 - Release Date: 12/15/10
>>>
>>>
>>> _______________________________________________
>>> 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.
>>>
>>
>>
>> --
>> "Neither the voice of authority nor the weight of reason and argument ar=
e
>> as significant as experiment, for thence comes quiet to the mind."
>> R. Bacon
>> "If you don't know what it is, don't poke it."
>> Ghost in the Shell
>>
>>
>> Dr. Don Latham AJ7LL
>> Six Mile Systems LLP
>> 17850 Six Mile Road
>> POB 134
>> Huson, MT, 59846
>> VOX 406-626-4304
>> www.lightningforensics.com
>> www.sixmilesystems.com
>>
>>
>> _______________________________________________
>> 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.
>>
>
>
>
> --
> =3D=3D=3D=3D=3D
> Chris Albertson
> Redondo Beach, California
>
> _______________________________________________
> 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