No subject


Mon Dec 13 16:21:17 UTC 2010


to take ownership of the project and run with it, make the web site,
write some golas and build "something" that works.  Only then do other
jump in and help.

It really would be good to have a Time and Frequency Instrumentation
Project as currently the state of the art seem to be that you simply
buy something from a Chinese eBay reseller.  This is hardly what I'd
cal "innovation."

On Thu, Dec 16, 2010 at 7:44 PM, Bob Bownes <bownes at gmail.com> wrote:
> Very good points.
>
> For the core counter, are you talking about an interval counter or a
> more generic two input, tell the CPU what to do with the inputs kind
> of model? :)
>
> USB certainly would be the interface of choice, but serial also has
> it's place. The joy is there is less software to write. That engenders
> a whole discussion about a standalone counter vs a PC based counter.
> Fine example is the two VNA projects out there. One of them requires a
> whole bunch of ugly USB drivers to work and it isn't even recognized
> by a Mac for example. You can still do spiffy GUI front ends and
> USB<->serial adaptors are going to be around for a while. Or you use
> an Arduino core and don't worry about drivers. Gonna be a religious
> war I suspect. Standalone model circumvents all that. :)
>
> I suspect a number of input modules could be described. Prescalers,
> amplifiers, attenuators, terminations, filters, all come to mind
> looking at the input options on gear on the bench. I have a nice
> variant on the VE2ZAZ design already done that would get it up to
> ~18Ghz.
>
> Again, several core synthesizers could be defined based on
> requirments. GPSDO, 10Mhz in, txco all come to mind.
>
> Define a power supply that doesn't exceed 12v and you are in pretty
> good shape. COT technology would be a good choice.
>
> The point about the TAPR bus and enclosure is also a great one. PC
> cases are nice, but bulky. Last thing I want is another one of those
> kicking around. 1U rackmount would be nice, but makes the module
> design difficult. 2U much easier, but harder to come by cheap cases.
>
> I think an overall target design would be the place to start. PICTIC
> II is also a good place to start. Shoot for a 10x improvement? :)
>
> I'm not all that fond of Wiki's but if there are people serious about
> the project, I can put one up. Main mailing list certainly isn't the
> place to design it. All that said, I don't know enough to design it
> alone, but I have the ability to fabricate prototypes and can build to
> someone else's specs. And I'm serious about wanting a better counter
> than my 5328. :)
>
> Bob
>
>
>
> On Thu, Dec 16, 2010 at 9:53 PM, Chris Albertson
> <albertson.chris at gmail.com> wrote:
>> You can't do anything, not even guess at a price until you have a list
>> of requirements written down. =A0And they need to be detailed.
>>
>> I would break the project down into a set of sub-projects possably like =
this
>>
>> 1) The "core" counter, just counts, no pre scaler, no display or
>> reference oscillator. connects to computer with USB.
>> 2) A display and control panel to the instrument can be independent of
>> a computer.
>> 3) The "front end" pre-scaler or other kind of signal conditioning unit.
>> 4) A core frequency synthesizer, no display and so on like the core coun=
ters
>> 5) A A/C mains based power supply
>> 6) A battery based power supply to be used in place of or in addition to=
 #4
>>
>> If these parts all worked together or at least used the same size PCB
>> people could get a chassis and start out simple and cheap and build up
>> a larger system over time. =A0 I was going to build a radio this way
>> once, I may still do it. =A0My idea was to make each card or modular the
>> same size as a hard disk drive. =A0Then I could use an old sever chassis
>> intended for hold SCSI disk drives to hold the cards and each card
>> would have knobs and controls on one end and electrilcal connectors of
>> the other. =A0Id use a standard scsi 50-pin ribon cable as a backplane
>> for serial control (i2c) and power. =A0Today I'd use a SATA backplane as
>> the form factor. =A0They can be pushed into a rack from the front
>> Something like this :
>> http://www.sansdigital.com/images/stories/products/HDDRACK5/hddrack5_1.j=
pg
>>
>> The mistakes made by the HPSDR people were that each card is far to
>> complex. =A0So much so that few people could understand and contribute
>> to the design and the cards are mostly un-build-able at the hobby
>> level. =A0and also they did not select an off the self backplane and
>> enclosure. =A0For most people sheet metal bending is not easy, So you'd
>> want to specify a common and cheap off the shelf chassis type.
>>
>> So,... the first step is to list out the cards and write specs for
>> each and design it so it is an expandable system =A0 =A0A Wiki works bes=
t
>> for this, not an email list.
>>
>> On Thu, Dec 16, 2010 at 5:15 PM, Alan Hochhalter <alanh137 at comcast.net> =
wrote:
>>> One way to find out if people are interested enough to pledge some mone=
y up
>>> front is something like this project
>>>
>>> http://www.kickstarter.com/projects/bushing/openvizsla-open-source-usb-=
protocol-analyzer
>>>
>>> Alan
>>>
>>> On 12/16/2010 12:55 PM, Bob Camp 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 mig=
ht
>>>> indeed make sense.
>>>>
>>>> Bob
>>>>
>>>> -----Original Message-----
>>>> From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] O=
n
>>>> 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 w=
here
>>>> the modules =A0have easy and well defined interfaces and where each =
=A0can
>>>> 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 th=
e
>>>> HPSDR project did this
>>>>
>>>> On Thu, Dec 16, 2010 at 11:20 AM, Bob Camp<lists at rtty.us> =A0wrote:
>>>>>
>>>>> 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 (Dig=
ikey
>>>>> has them), a few of these and a couple of those. Spend less than $100=
 and
>>>>> 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 mm
>>>>> spacing BGA package down on the pc board. Not so easy without the rig=
ht
>>>>> 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 count=
er?
>>>>> We've seen thorough discussions about trigger jitter, which IMHO is t=
he
>>>>> fundamental problem. And isn't the PIC2 Time base from 10 MHz standar=
d,
>>>>> all else should be straightforward.
>>>>> I'm not a designer, just a messer-arounder, or I'd give it a shot. Ro=
bot
>>>>> 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 Mixer=
s
>>>>>> but
>>>>>> 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 =
pretty
>>>>>> 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 ha=
ve 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
>>>>>> (<$400)
>>>>>> 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 membe=
rs
>>>>>> of
>>>>>> the group discuss. =A0I know that new equipment is far out of my bud=
get,
>>>>
>>>> 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 s=
ince
>>>>>> manuals are much easier to find than most other brands.
>>>>>> I'd also like recommendation for a good low-cost GPIB controller tha=
t
>>>>>> 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 =
these
>>>>>> controllers on the Bay and other online vendors, but I've not locate=
d
>>>>>> the
>>>>>> 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
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10
>>>>>>
>>>>>>
>>>>>> _______________________________________________
>>>>>> time-nuts mailing list -- time-nuts at febo.com
>>>>>> To unsubscribe, go to
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>>>>>> and follow the instructions there.
>>>>>>
>>>>>
>>>>> --
>>>>> "Neither the voice of authority nor the weight of reason and argument=
 are
>>>>> 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.
>>>>>
>>>>
>>>>
>>>
>>>
>>> _______________________________________________
>>> time-nuts mailing list -- time-nuts at febo.com
>>> To unsubscribe, go to
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>>> 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.
>>
>
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> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-=
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>



--=20
=3D=3D=3D=3D=3D
Chris Albertson
Redondo Beach, California



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