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Blocking RF from intentional radiators

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  Blocking RF from intentional radiators Don Y <blockedofcourse@foo.invalid> - 2017-02-06 00:40 -0700
    Re: Blocking RF from intentional radiators whit3rd <whit3rd@gmail.com> - 2017-02-06 00:56 -0800
      Re: Blocking RF from intentional radiators Don Y <blockedofcourse@foo.invalid> - 2017-02-06 02:19 -0700
        Re: Blocking RF from intentional radiators Robert Baer <robertbaer@localnet.com> - 2017-02-08 20:22 -0800
    Re: Blocking RF from intentional radiators piglet <erichpwagner@hotmail.com> - 2017-02-06 11:57 +0000
      Re: Blocking RF from intentional radiators "Tim Williams" <tiwill@seventransistorlabs.com> - 2017-02-06 06:51 -0600
      Re: Blocking RF from intentional radiators Don Y <blockedofcourse@foo.invalid> - 2017-02-06 06:52 -0700
        Re: Blocking RF from intentional radiators Jim Thompson <To-Email-Use-The-Envelope-Icon@On-My-Web-Site.com> - 2017-02-06 07:55 -0700
          Re: Blocking RF from intentional radiators Don Y <blockedofcourse@foo.invalid> - 2017-02-06 12:38 -0700
            Re: Blocking RF from intentional radiators Tim Wescott <seemywebsite@myfooter.really> - 2017-02-06 14:18 -0600
              Re: Blocking RF from intentional radiators Don Y <blockedofcourse@foo.invalid> - 2017-02-06 14:39 -0700
                Re: Blocking RF from intentional radiators Jon Elson <jmelson@wustl.edu> - 2017-02-06 17:10 -0600
                  Re: Blocking RF from intentional radiators Don Y <blockedofcourse@foo.invalid> - 2017-02-06 17:06 -0700
                    Re: Blocking RF from intentional radiators Jasen Betts <jasen@xnet.co.nz> - 2017-02-07 04:12 +0000
                Re: Blocking RF from intentional radiators Jasen Betts <jasen@xnet.co.nz> - 2017-02-07 04:05 +0000
            Re: Blocking RF from intentional radiators Jim Thompson <To-Email-Use-The-Envelope-Icon@On-My-Web-Site.com> - 2017-02-06 14:56 -0700
              Re: Blocking RF from intentional radiators Don Y <blockedofcourse@foo.invalid> - 2017-02-06 15:18 -0700
          Re: Blocking RF from intentional radiators Robert Baer <robertbaer@localnet.com> - 2017-02-08 20:41 -0800
        Re: Blocking RF from intentional radiators Robert Baer <robertbaer@localnet.com> - 2017-02-08 20:32 -0800
      Re: Blocking RF from intentional radiators Phil Allison <pallison49@gmail.com> - 2017-02-06 06:39 -0800
    Re: Blocking RF from intentional radiators John Larkin <jjlarkin@highlandtechnology.com> - 2017-02-06 08:28 -0800
    Re: Blocking RF from intentional radiators Jeff Liebermann <jeffl@cruzio.com> - 2017-02-06 09:23 -0800
      Re: Blocking RF from intentional radiators Lasse Langwadt Christensen <langwadt@fonz.dk> - 2017-02-06 09:30 -0800
      Re: Blocking RF from intentional radiators Don Y <blockedofcourse@foo.invalid> - 2017-02-06 11:52 -0700
        Re: Blocking RF from intentional radiators Jeff Liebermann <jeffl@cruzio.com> - 2017-02-06 11:31 -0800
          Re: Blocking RF from intentional radiators Don Y <blockedofcourse@foo.invalid> - 2017-02-06 12:49 -0700
            Re: Blocking RF from intentional radiators John S <Sophi.2@invalid.org> - 2017-02-06 14:07 -0600
            Re: Blocking RF from intentional radiators "nuny@bid.nes" <Alien8752@gmail.com> - 2017-02-06 12:09 -0800
              Re: Blocking RF from intentional radiators Don Y <blockedofcourse@foo.invalid> - 2017-02-06 13:37 -0700
                Re: Blocking RF from intentional radiators "nuny@bid.nes" <Alien8752@gmail.com> - 2017-02-06 14:35 -0800
                  Re: Blocking RF from intentional radiators Don Y <blockedofcourse@foo.invalid> - 2017-02-06 15:59 -0700
            Re: Blocking RF from intentional radiators Jeff Liebermann <jeffl@cruzio.com> - 2017-02-06 17:56 -0800
        Re: Blocking RF from intentional radiators George Herold <gherold@teachspin.com> - 2017-02-06 12:03 -0800
          Re: Blocking RF from intentional radiators Don Y <blockedofcourse@foo.invalid> - 2017-02-06 13:31 -0700
            Re: Blocking RF from intentional radiators George Herold <gherold@teachspin.com> - 2017-02-06 13:29 -0800
              Re: Blocking RF from intentional radiators Lasse Langwadt Christensen <langwadt@fonz.dk> - 2017-02-06 13:32 -0800
              Re: Blocking RF from intentional radiators Don Y <blockedofcourse@foo.invalid> - 2017-02-06 15:01 -0700
                Re: Blocking RF from intentional radiators Jim Thompson <To-Email-Use-The-Envelope-Icon@On-My-Web-Site.com> - 2017-02-06 15:07 -0700
                  Re: Blocking RF from intentional radiators Don Y <blockedofcourse@foo.invalid> - 2017-02-06 15:13 -0700
                    Re: Blocking RF from intentional radiators Lasse Langwadt Christensen <langwadt@fonz.dk> - 2017-02-06 14:28 -0800
                      Re: Blocking RF from intentional radiators Don Y <blockedofcourse@foo.invalid> - 2017-02-06 15:31 -0700
                    Re: Blocking RF from intentional radiators Jim Thompson <To-Email-Use-The-Envelope-Icon@On-My-Web-Site.com> - 2017-02-06 15:59 -0700
                      Re: Blocking RF from intentional radiators Don Y <blockedofcourse@foo.invalid> - 2017-02-06 17:08 -0700
                        Re: Blocking RF from intentional radiators pcdhobbs@gmail.com - 2017-02-08 16:36 -0800
                    Re: Blocking RF from intentional radiators Clifford Heath <no.spam@please.net> - 2017-02-07 10:26 +1100
        Re: Blocking RF from intentional radiators whit3rd <whit3rd@gmail.com> - 2017-02-06 13:05 -0800
          Re: Blocking RF from intentional radiators Don Y <blockedofcourse@foo.invalid> - 2017-02-06 14:22 -0700
            Re: Blocking RF from intentional radiators kevin93 <kevin@whitedigs.com> - 2017-02-06 13:39 -0800
              Re: Blocking RF from intentional radiators Don Y <blockedofcourse@foo.invalid> - 2017-02-06 15:12 -0700
            Re: Blocking RF from intentional radiators whit3rd <whit3rd@gmail.com> - 2017-02-06 14:43 -0800
              Re: Blocking RF from intentional radiators "nuny@bid.nes" <Alien8752@gmail.com> - 2017-02-06 16:29 -0800
        Re: Blocking RF from intentional radiators Jasen Betts <jasen@xnet.co.nz> - 2017-02-07 04:19 +0000

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#446425

On Mon, 6 Feb 2017 00:40:44 -0700, Don Y <blockedofcourse@foo.invalid>
wrote:

>How can I economically, simply and reversibly inhibit the
>RF link to a GDO?  Short the antenna?  Slip it in a
>grounded copper tube?  etc.

Put it in a DBCC.


-- 

John Larkin         Highland Technology, Inc

lunatic fringe electronics 

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#446429

On Mon, 6 Feb 2017 00:40:44 -0700, Don Y <blockedofcourse@foo.invalid>
wrote:

>How can I economically, simply and reversibly inhibit the
>RF link to a GDO?  Short the antenna?  Slip it in a
>grounded copper tube?  etc.

Garage Door Opener?
11th Commandment:  Thou shalt not abrev.

1.  Change the code to something invalid (dip switches).
2.  Detune the receiver.  A piece of ferrite near the TRF (tuned RF)
receiving coil should be sufficient.
3.  Remove the antenna.  That's won't disable the receiver but will
reduce the sensitivity.
4.  Wrap the receiver in aluminum foil.  Most receivers are on a
seperate PCB.  However, the leads are usually badly bypassed and it
will still activate if the transmitter is nearby or very powerful.
5.  Wrap the entire GDO in aluminum foil.  Messy, but probably
effective.
6.  Unplug the receiver section.  Most receivers are on a seperate PCB
or module.
7.  If unplugging the receiver is awkward, just insert a SPDT switch
in the power lead.

Now, I have a dumb question.  What problem are you trying to solve?

-- 
Jeff Liebermann     jeffl@cruzio.com
150 Felker St #D    http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann     AE6KS    831-336-2558

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#446431

Den mandag den 6. februar 2017 kl. 18.23.20 UTC+1 skrev Jeff Liebermann:
> On Mon, 6 Feb 2017 00:40:44 -0700, Don Y <blockedofcourse@foo.invalid>
> wrote:
> 
> >How can I economically, simply and reversibly inhibit the
> >RF link to a GDO?  Short the antenna?  Slip it in a
> >grounded copper tube?  etc.
> 
> Garage Door Opener?
> 11th Commandment:  Thou shalt not abrev.
> 
> 1.  Change the code to something invalid (dip switches).
> 2.  Detune the receiver.  A piece of ferrite near the TRF (tuned RF)
> receiving coil should be sufficient.
> 3.  Remove the antenna.  That's won't disable the receiver but will
> reduce the sensitivity.
> 4.  Wrap the receiver in aluminum foil.  Most receivers are on a
> seperate PCB.  However, the leads are usually badly bypassed and it
> will still activate if the transmitter is nearby or very powerful.
> 5.  Wrap the entire GDO in aluminum foil.  Messy, but probably
> effective.
> 6.  Unplug the receiver section.  Most receivers are on a seperate PCB
> or module.
> 7.  If unplugging the receiver is awkward, just insert a SPDT switch
> in the power lead.
> 
> Now, I have a dumb question.  What problem are you trying to solve?

given that it is Don that is asking I'm not sure it matters, any proposed solution won't be quite generic enough to cover all possible and impossible 
use cases from the garage door was invented till the sun burns out so it 
won't work
 
;)

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#446442

On 2/6/2017 10:23 AM, Jeff Liebermann wrote:
> On Mon, 6 Feb 2017 00:40:44 -0700, Don Y <blockedofcourse@foo.invalid>
> wrote:
>
>> How can I economically, simply and reversibly inhibit the
>> RF link to a GDO?  Short the antenna?  Slip it in a
>> grounded copper tube?  etc.
>
> Garage Door Opener?
> 11th Commandment:  Thou shalt not abrev.

Sorry, I post in a variety of groups and don't always remember what folks
will recognize as "norms".

> 1.  Change the code to something invalid (dip switches).
> 2.  Detune the receiver.  A piece of ferrite near the TRF (tuned RF)
> receiving coil should be sufficient.
> 3.  Remove the antenna.  That's won't disable the receiver but will
> reduce the sensitivity.
> 4.  Wrap the receiver in aluminum foil.  Most receivers are on a
> seperate PCB.  However, the leads are usually badly bypassed and it
> will still activate if the transmitter is nearby or very powerful.
> 5.  Wrap the entire GDO in aluminum foil.  Messy, but probably
> effective.
> 6.  Unplug the receiver section.  Most receivers are on a seperate PCB
> or module.
> 7.  If unplugging the receiver is awkward, just insert a SPDT switch
> in the power lead.
>
> Now, I have a dumb question.  What problem are you trying to solve?

I want Joe Average User to be able to cripple the "wireless" activation/control
of his opener -- without having to disassemble it *or* consult an exhaustive
compilation of "if you have model X, do this" rules.

Once crippled -- and until "restored" -- neither his remote nor any OTHER
remote should be able to affect the operation of the opener.

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#446445

On Mon, 6 Feb 2017 11:52:05 -0700, Don Y <blockedofcourse@foo.invalid>
wrote:

>I want Joe Average User

I prefer the GUM (great unwashed masses).  The problem with average is
that a few super-intelligent users nicely balance an ever growing
horde of users with limited intelligence.  If you don't like GUM, I
suggest Joe Median User, which is half way between equal numbers of
intelligent and dumb users.

>to be able to cripple the "wireless" activation/control
>of his opener -- without having to disassemble it *or* consult an exhaustive
>compilation of "if you have model X, do this" rules.
>
>Once crippled -- and until "restored" -- neither his remote nor any OTHER
>remote should be able to affect the operation of the opener.

In other words don't touch, tweak, modify, add, remove, or change
anything.  I don't think that's possible.  

I guess the minimally invasive solution would be some kind of adapter
that goes between the mechanics of the GDO and the receiver.  The
wires to a GDO are normally screw terminals so this could be a PCB
with spade lugs on one side, and screw terminals on the other.  A
simple on/off switch to turn off the power to the receiver would be
the minimum.  Presumably, the members of the GUM are qualified to
operate a screwdriver.  If you need subterfuge, a few magnetic reed
switches and some potting compound should work.

You still haven't answered my question.  What problem are you trying
to solve?

-- 
Jeff Liebermann     jeffl@cruzio.com
150 Felker St #D    http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann     AE6KS    831-336-2558

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#446447

On 2/6/2017 12:31 PM, Jeff Liebermann wrote:
> On Mon, 6 Feb 2017 11:52:05 -0700, Don Y <blockedofcourse@foo.invalid>
> wrote:
>
>> I want Joe Average User
>
> I prefer the GUM (great unwashed masses).  The problem with average is
> that a few super-intelligent users nicely balance an ever growing
> horde of users with limited intelligence.  If you don't like GUM, I
> suggest Joe Median User, which is half way between equal numbers of
> intelligent and dumb users.

I'd be happy raising the bar to the level of "folks who CAN install/replace
their own opener" -- but suspect even this is a big hurdle for many!
Despite the "See Spot!  See Spot Run!" sort of instructions that typically
accompany them (and the fact that the mechanical mounts are usually already
in place for the more common REPLACEMENT vs. NEW INSTALL.

Beyond that, having to provide make/model specific instructions as to how
to disassemble an already installed unit and modify it ("short R1 located
adjacent to ...") is just too much to codify AND too much to expect from
the user!

>> to be able to cripple the "wireless" activation/control
>> of his opener -- without having to disassemble it *or* consult an exhaustive
>> compilation of "if you have model X, do this" rules.
>>
>> Once crippled -- and until "restored" -- neither his remote nor any OTHER
>> remote should be able to affect the operation of the opener.
>
> In other words don't touch, tweak, modify, add, remove, or change
> anything.  I don't think that's possible.

The obvious solution is to interfere with the ACCESSIBLE antenna.

> I guess the minimally invasive solution would be some kind of adapter
> that goes between the mechanics of the GDO and the receiver.  The
> wires to a GDO are normally screw terminals so this could be a PCB
> with spade lugs on one side, and screw terminals on the other.  A
> simple on/off switch to turn off the power to the receiver would be
> the minimum.  Presumably, the members of the GUM are qualified to
> operate a screwdriver.  If you need subterfuge, a few magnetic reed
> switches and some potting compound should work.

But the electronics in the opener typically INTEGRATE the receiver
functionality with the "logic" to power the mechanism, sense stall
current, limit switches, etc.  You'd want to preserve that but
not allow the receiver to interact with it (i.e., initiate activity)

> You still haven't answered my question.  What problem are you trying
> to solve?

I want to disable the wireless control of the opener.  Jim's opener
has a FEATURE that allows this.  So, how do you retrofit that
feature to other openers, without requiring the opener to be
replaced or the owner/user to undertake some disassembly activity
that can potentially irreparably damage the opener?

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#446449

On 2/6/2017 1:49 PM, Don Y wrote:
> On 2/6/2017 12:31 PM, Jeff Liebermann wrote:
>> On Mon, 6 Feb 2017 11:52:05 -0700, Don Y <blockedofcourse@foo.invalid>
>> wrote:
>>
>>> I want Joe Average User
>>
>> I prefer the GUM (great unwashed masses).  The problem with average is
>> that a few super-intelligent users nicely balance an ever growing
>> horde of users with limited intelligence.  If you don't like GUM, I
>> suggest Joe Median User, which is half way between equal numbers of
>> intelligent and dumb users.
>
> I'd be happy raising the bar to the level of "folks who CAN install/replace
> their own opener" -- but suspect even this is a big hurdle for many!
> Despite the "See Spot!  See Spot Run!" sort of instructions that typically
> accompany them (and the fact that the mechanical mounts are usually already
> in place for the more common REPLACEMENT vs. NEW INSTALL.
>
> Beyond that, having to provide make/model specific instructions as to how
> to disassemble an already installed unit and modify it ("short R1 located
> adjacent to ...") is just too much to codify AND too much to expect from
> the user!
>
>>> to be able to cripple the "wireless" activation/control
>>> of his opener -- without having to disassemble it *or* consult an
>>> exhaustive
>>> compilation of "if you have model X, do this" rules.
>>>
>>> Once crippled -- and until "restored" -- neither his remote nor any
>>> OTHER
>>> remote should be able to affect the operation of the opener.
>>
>> In other words don't touch, tweak, modify, add, remove, or change
>> anything.  I don't think that's possible.
>
> The obvious solution is to interfere with the ACCESSIBLE antenna.
>
>> I guess the minimally invasive solution would be some kind of adapter
>> that goes between the mechanics of the GDO and the receiver.  The
>> wires to a GDO are normally screw terminals so this could be a PCB
>> with spade lugs on one side, and screw terminals on the other.  A
>> simple on/off switch to turn off the power to the receiver would be
>> the minimum.  Presumably, the members of the GUM are qualified to
>> operate a screwdriver.  If you need subterfuge, a few magnetic reed
>> switches and some potting compound should work.
>
> But the electronics in the opener typically INTEGRATE the receiver
> functionality with the "logic" to power the mechanism, sense stall
> current, limit switches, etc.  You'd want to preserve that but
> not allow the receiver to interact with it (i.e., initiate activity)
>
>> You still haven't answered my question.  What problem are you trying
>> to solve?
>
> I want to disable the wireless control of the opener.  Jim's opener
> has a FEATURE that allows this.  So, how do you retrofit that
> feature to other openers, without requiring the opener to be
> replaced or the owner/user to undertake some disassembly activity
> that can potentially irreparably damage the opener?
>

Geeze, what a waste of time.

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#446450

On Monday, February 6, 2017 at 11:49:25 AM UTC-8, Don Y wrote:
> On 2/6/2017 12:31 PM, Jeff Liebermann wrote:


> > You still haven't answered my question.  What problem are you trying
> > to solve?
> 
> I want to disable the wireless control of the opener.  Jim's opener
> has a FEATURE that allows this.  So, how do you retrofit that
> feature to other openers, without requiring the opener to be
> replaced or the owner/user to undertake some disassembly activity
> that can potentially irreparably damage the opener?

  No, Don, that's "defining the solution space", not the problem.

  Is there a rash of garage break-ins by crooks running through codes on generic replacement remotes or something?


  Mark L. Fergerson

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#446458

On 2/6/2017 1:09 PM, nuny@bid.nes wrote:
> On Monday, February 6, 2017 at 11:49:25 AM UTC-8, Don Y wrote:
>> On 2/6/2017 12:31 PM, Jeff Liebermann wrote:
>
>>> You still haven't answered my question.  What problem are you trying to
>>> solve?
>>
>> I want to disable the wireless control of the opener.  Jim's opener has a
>> FEATURE that allows this.  So, how do you retrofit that feature to other
>> openers, without requiring the opener to be replaced or the owner/user to
>> undertake some disassembly activity that can potentially irreparably
>> damage the opener?
>
> No, Don, that's "defining the solution space", not the problem.
>
> Is there a rash of garage break-ins by crooks running through codes on
> generic replacement remotes or something?

I don't want to encourage a long, digressionary evaluation of what I'm trying
to do, why, etc.  Then, have the *ninnies* grumble because of the wasted
bandwidth -- for something THEY can't fathom or in which they have no interest.

"Why" invites alternatives that I'm smart enough to have already ruled out.
And, have no desire to feel the need to justify those reasons to the ninnies.

I stated a clear problem.  I identified the constraints that govern the
solution.  The skill level, invertibility, cost constraints, etc.

If this is insufficient for folks to come up with a solution, then
knowing WHY won't help them solve THIS problem -- instead, it will
encourage them to try to solve some other, unrelated problem.

If I told you I wanted a DSRV that could operate at depths of 50 fathoms
and had a single manipulator that had to have a range of extension of 0-5
inches and the capacity to support a 5 pound weight in atmosphere, would
you need to know if I was planning on using it to retrieve old cannon balls
from the sea floor vs. *stones*?

Sure, you might be able to come up with an alternative -- knowing the intended
application.

Or, not.

Please trust me to understand MY application(s).  If you want to solve a
DIFFERENT problem -- possibly related to garage door openers -- please
feel free to posit that and its criteria.

[Hey, maybe I'm not really interested in garage door openers but just
use them as a representative example of the type of electronics, frequencies,
power levels, convenience, etc. that *are* important to me!  ;)  ]

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#446488

On Monday, February 6, 2017 at 12:37:10 PM UTC-8, Don Y wrote:
> On 2/6/2017 1:09 PM, nuny@bid.nes wrote:
> > On Monday, February 6, 2017 at 11:49:25 AM UTC-8, Don Y wrote:
> >> On 2/6/2017 12:31 PM, Jeff Liebermann wrote:
> >
> >>> You still haven't answered my question.  What problem are you trying to
> >>> solve?
> >>
> >> I want to disable the wireless control of the opener.  Jim's opener has a
> >> FEATURE that allows this.  So, how do you retrofit that feature to other
> >> openers, without requiring the opener to be replaced or the owner/user to
> >> undertake some disassembly activity that can potentially irreparably
> >> damage the opener?
> >
> > No, Don, that's "defining the solution space", not the problem.
> >
> > Is there a rash of garage break-ins by crooks running through codes on
> > generic replacement remotes or something?
> 
> I don't want to encourage a long, digressionary evaluation of what I'm trying
> to do, why, etc.  Then, have the *ninnies* grumble because of the wasted
> bandwidth -- for something THEY can't fathom or in which they have no
> interest.

  Aw, Don, this is the INTERNET- where else are we gonna go?

> "Why" invites alternatives that I'm smart enough to have already ruled out.
> And, have no desire to feel the need to justify those reasons to the ninnies.

  Well, that's nice and all, but how do you know for sure that all the alternatives you've ruled out are the only possible alternatives? I sure don't.

> I stated a clear problem.  I identified the constraints that govern the
> solution.  The skill level, invertibility, cost constraints, etc.

  Trouble is it's way too broad. I mean, there are all sorts of ways for an unskilled individual to "blind" an RF receiver but which you use depends on the band, the signal strength at the receiver, the antenna placement, the weather...

  Knowing which to use is where the skill comes in.

> If this is insufficient for folks to come up with a solution, then
> knowing WHY won't help them solve THIS problem -- instead, it will
> encourage them to try to solve some other, unrelated problem.

  Hell, there's an overload cutout on mine that auto-disables it if the motor draws too much current. A bolt stuck through the holes in the door and track works just fine to prevent unauthorized entry and harms nothing. If I want to open the door without using the remote I just pull the bolt out and hit the button.

  But that won't work for *all* GDOs.

> If I told you I wanted a DSRV that could operate at depths of 50 fathoms
> and had a single manipulator that had to have a range of extension of 0-5
> inches and the capacity to support a 5 pound weight in atmosphere, would
> you need to know if I was planning on using it to retrieve old cannon balls
> from the sea floor vs. *stones*?

  See, I might suggest a magnet instead of a claw, but first you have to tell me what the cannon balls are made of.

> Sure, you might be able to come up with an alternative -- knowing the intended
> application.
> 
> Or, not.

  But you won't know until you ask.

> Please trust me to understand MY application(s).  If you want to solve a
> DIFFERENT problem -- possibly related to garage door openers -- please
> feel free to posit that and its criteria.

  Thing is, you haven't told us what the problem *is*. Per what you say below you're asking for a noninvasive reversible one-size-fits-all method for blinding *any* RF receiver that an untrained individual can implement reliably.

  There ain't no such animal.

> [Hey, maybe I'm not really interested in garage door openers but just
> use them as a representative example of the type of electronics, frequencies,
> power levels, convenience, etc. that *are* important to me!  ;)  ]

  Then you've opened the solution space even farther. Suppose you *really* want to disable the WiFi on your laptop without getting into the settings while still leaving the laptop usable standalone? First I need to know where the antenna(s) is/are, which I can't do without opening it up, and my solution is almost guaranteed NOT to work for your class-representative GDO. Nor are there any holes to stick a bolt through...

  So here are the solution parameters I can identify; noninvasively and reversibly prevent an RF receiver from seeing enough of an incoming signal to activate a programmed response without RF electronics or mechanical expertise.

  If that was a test question on a job application I'd apply elsewhere..


  Mark L. Fergerson

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#446492

>>>>> You still haven't answered my question.  What problem are you trying
>>>>> to solve?
>>>>
>>>> I want to disable the wireless control of the opener.  Jim's opener
>>>> has a FEATURE that allows this.  So, how do you retrofit that feature
>>>> to other openers, without requiring the opener to be replaced or the
>>>> owner/user to undertake some disassembly activity that can potentially
>>>> irreparably damage the opener?
>>>
>>> No, Don, that's "defining the solution space", not the problem.
>>>
>>> Is there a rash of garage break-ins by crooks running through codes on
>>> generic replacement remotes or something?
>>
>> I don't want to encourage a long, digressionary evaluation of what I'm
>> trying to do, why, etc.  Then, have the *ninnies* grumble because of the
>> wasted bandwidth -- for something THEY can't fathom or in which they have
>> no interest.
>
> Aw, Don, this is the INTERNET- where else are we gonna go?

(sigh)

>> "Why" invites alternatives that I'm smart enough to have already ruled
>> out. And, have no desire to feel the need to justify those reasons to the
>> ninnies.
>
> Well, that's nice and all, but how do you know for sure that all the
> alternatives you've ruled out are the only possible alternatives? I sure
> don't.

I'm willing to trust my appraisal of "the alternatives".  I surely wouldn't 
want to inconvenience the likes of Lasse by LISTING all of the things I've
considered!  And, the reasons why I've ruled them out...

>> I stated a clear problem.  I identified the constraints that govern the
>> solution.  The skill level, invertibility, cost constraints, etc.
>
> Trouble is it's way too broad. I mean, there are all sorts of ways for an
> unskilled individual to "blind" an RF receiver but which you use depends on
> the band, the signal strength at the receiver, the antenna placement, the
> weather...

That's why I posed a specific application instead of "how do I interfere with
RF reception".

> Knowing which to use is where the skill comes in.
>
>> If this is insufficient for folks to come up with a solution, then knowing
>> WHY won't help them solve THIS problem -- instead, it will encourage them
>> to try to solve some other, unrelated problem.
>
> Hell, there's an overload cutout on mine that auto-disables it if the motor
> draws too much current. A bolt stuck through the holes in the door and track
> works just fine to prevent unauthorized entry and harms nothing. If I want
> to open the door without using the remote I just pull the bolt out and hit
> the button.
>
> But that won't work for *all* GDOs.

I could flip the breaker and achieve a similar result.  Do we want to turn this
thread into a lengthy discussion of all the POSSIBLE ways to interfere with
the "remote" operation of the opener?  Or, do we want to look at the IMPLIED
mechanism by which I'm hoping it can be disabled?

>> If I told you I wanted a DSRV that could operate at depths of 50 fathoms
>> and had a single manipulator that had to have a range of extension of 0-5
>> inches and the capacity to support a 5 pound weight in atmosphere, would
>> you need to know if I was planning on using it to retrieve old cannon
>> balls from the sea floor vs. *stones*?
>
> See, I might suggest a magnet instead of a claw, but first you have to tell
> me what the cannon balls are made of.

And, if they aren't cannonballs but rocks, instead?

[Remember, we're on a budget not to type more characters than Lasse has the
patience to read!  :> ]

>> Sure, you might be able to come up with an alternative -- knowing the
>> intended application.
>>
>> Or, not.
>
> But you won't know until you ask.

But I've already explored the alternate solution spaces.  And, ruled those
options out.  It's easy to come up with a limitless menu of options if
you ignore ALL constraints.  Do I need "you guys" to determine that
the criteria I am applying are appropriate FOR MY APPLICATION?

I think its arrogant to presume that a poster doesn't understand their
own application domain.  And, expect them to EDUCATE you on it to "prove"
their throughness in analyzing the available options.

Then, *whine* when they type more than the THREE SENTENCES in the
original post!

Do you REALLY question every criteria/constraint your clients/employers
impose on you?  Do you wonder why you have to be at your desk certain
hours of the day?  Why the facility is located on the north side of the
street (which necessitates making a U-turn to enter the parking lot)
instead of the South?  etc.

Do you really think everyone else is incapable of coming to conclusions?

>> Please trust me to understand MY application(s).  If you want to solve a
>> DIFFERENT problem -- possibly related to garage door openers -- please
>> feel free to posit that and its criteria.
>
> Thing is, you haven't told us what the problem *is*. Per what you say below
> you're asking for a noninvasive reversible one-size-fits-all method for
> blinding *any* RF receiver that an untrained individual can implement
> reliably.

No.  I posed a specific case:
     How can I economically, simply and reversibly inhibit the RF link to a GDO?
I embelished this to show other reasons why similar things could be of
interest -- because folks couldn't relate to the simple, concise example that
I originally presented.  So they wouldn't fixate on "my" garage door opener
and the class of people in the neighborhood.  Or, *my* WiFi router. Or...

But, once you generalize, then folks complain that you've added far more
text to the description of the problem and confused them in the process.

I don't do RF.  Someone could easily and instructively have said:
     "You have to eliminate all means by which the radiated energy can
     find its way into the circuit.  These include radiated through open
     air, conducted through ungrounded surfaces, etc.  The sizes of any
     'vulnerable' openings are related to the fundamental frequency by the
     formula...  The field intensity falls off as..."

     "With these things in mind, for a GDO, the frequencies used are
     typically ... at power levels of ...  So, any opening larger
     than X needs to be obstructed and N layers of grounded shields
     need to surround the front end to ensure an attenuation below
     <whatever is typical for a GDO's receiver> at a distance of Y"
For someone "skilled in the art", this should be a piece of cake, right?
Sort of like asking me how quickly I have to clear the Rx holding register in
a UART given a particular operating bit rate and some number of competing
IRQ's at different service latencies.

> There ain't no such animal.
>
>> [Hey, maybe I'm not really interested in garage door openers but just use
>> them as a representative example of the type of electronics, frequencies,
>> power levels, convenience, etc. that *are* important to me!  ;)  ]
>
> Then you've opened the solution space even farther. Suppose you *really*
> want to disable the WiFi on your laptop without getting into the settings
> while still leaving the laptop usable standalone? First I need to know where
> the antenna(s) is/are, which I can't do without opening it up, and my
> solution is almost guaranteed NOT to work for your class-representative GDO.
> Nor are there any holes to stick a bolt through...

You'll note that I did NOT mention these examples in my OP!  I.e., I
made a deliberate effort to restrict the appication domain and the ensuing
discussion.

> So here are the solution parameters I can identify; noninvasively and
> reversibly prevent an RF receiver from seeing enough of an incoming signal
> to activate a programmed response without RF electronics or mechanical
> expertise.
>
> If that was a test question on a job application I'd apply elsewhere..

So, you wouldn't be hired at a garage door opener manufacturer because
you abstracted the question beyond what was ASKED!

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#446563

On Mon, 6 Feb 2017 12:49:10 -0700, Don Y <blockedofcourse@foo.invalid>
wrote:

>The obvious solution is to interfere with the ACCESSIBLE antenna.

That's not a solution because the receiver will still function when
the remote control transmitter is fairly close to the receiver.  Even
if you short the antenna to ground, there will still be some pickup
through the usual plastic case to the receiver front end.

>But the electronics in the opener typically INTEGRATE the receiver
>functionality with the "logic" to power the mechanism, sense stall
>current, limit switches, etc.  You'd want to preserve that but
>not allow the receiver to interact with it (i.e., initiate activity)

Really?  Looking at the photos belched by a "garage door opener
receiver" image search:
<https://www.google.com/search?q=garage+door+opener+receiver&tbm=isch>
If find a fairly large number of garage door openers with external
receivers.  That's common because the range of the typical receiver is
so short, that locating the receiver closer to where the owner is
likely to push the transmitter button is often a necessity.  In the
devices that I've tinkered with, the receiver is in an external
plastic box, with 3 to 5 terminals.  The output (contact closure)
terminals are in parallel with the push button switch and key that
activates the door opening.  Like this:
<http://s.hswstatic.com/gif/how-to-repair-a-garage-door-6.jpg>
The main housing, that contains the motor and some electronics,
provide the features you mentioned above (as well as timing,
interlocks, safety, etc).

>> You still haven't answered my question.  What problem are you trying
>> to solve?

>I want to disable the wireless control of the opener.

That answers the question "What solutions have you proposed so far"?
Disabling the wireless is a solution to a problem which you haven't
disclosed.  As you noted elsewhere, it's not really necessary in order
to answer your question, unless you may have limited yourself to this
one solution which is neither optimum or practical.  Disclosing the
original problem allows you to investigate some of the alternatives.
Limiting acceptable answers to only those that follow your line of
reasoning is a great way stifle creativity and innovation.

>Jim's opener
>has a FEATURE that allows this.  So, how do you retrofit that
>feature to other openers, without requiring the opener to be
>replaced or the owner/user to undertake some disassembly activity
>that can potentially irreparably damage the opener?

I believe I explained how that could be done.  In case you missed it:

  I guess the minimally invasive solution would be some kind of
  adapter that goes between the mechanics of the GDO and the receiver.
  The wires to a GDO are normally screw terminals so this could be 
  a PCB with spade lugs on one side, and screw terminals on the other.
A simple on/off switch to turn off the power to the receiver would
  be the minimum.  Presumably, the members of the GUM are qualified 
  to operate a screwdriver.  If you need subterfuge, a few magnetic
  reed switches and some potting compound should work.

Basically, a box, PCB, or wiring between the main motor box, and the 3
to 5 wires that run the receiver.


-- 
Jeff Liebermann     jeffl@cruzio.com
150 Felker St #D    http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann     AE6KS    831-336-2558

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#446448

On Monday, February 6, 2017 at 1:52:22 PM UTC-5, Don Y wrote:
> On 2/6/2017 10:23 AM, Jeff Liebermann wrote:
> > On Mon, 6 Feb 2017 00:40:44 -0700, Don Y <blockedofcourse@foo.invalid>
> > wrote:
> >
> >> How can I economically, simply and reversibly inhibit the
> >> RF link to a GDO?  Short the antenna?  Slip it in a
> >> grounded copper tube?  etc.
> >
> > Garage Door Opener?
> > 11th Commandment:  Thou shalt not abrev.
> 
> Sorry, I post in a variety of groups and don't always remember what folks
> will recognize as "norms".
> 
> > 1.  Change the code to something invalid (dip switches).
> > 2.  Detune the receiver.  A piece of ferrite near the TRF (tuned RF)
> > receiving coil should be sufficient.
> > 3.  Remove the antenna.  That's won't disable the receiver but will
> > reduce the sensitivity.
> > 4.  Wrap the receiver in aluminum foil.  Most receivers are on a
> > seperate PCB.  However, the leads are usually badly bypassed and it
> > will still activate if the transmitter is nearby or very powerful.
> > 5.  Wrap the entire GDO in aluminum foil.  Messy, but probably
> > effective.
> > 6.  Unplug the receiver section.  Most receivers are on a seperate PCB
> > or module.
> > 7.  If unplugging the receiver is awkward, just insert a SPDT switch
> > in the power lead.
> >
> > Now, I have a dumb question.  What problem are you trying to solve?
> 
> I want Joe Average User to be able to cripple the "wireless" activation/control
> of his opener -- without having to disassemble it *or* consult an exhaustive
> compilation of "if you have model X, do this" rules.
> 
> Once crippled -- and until "restored" -- neither his remote nor any OTHER
> remote should be able to affect the operation of the opener.

Don,  Can I repeat Jeff's question. 
 "Now, I have a dumb question.  What problem are you trying to solve?"

If I wanted to disable my garage door opener, I'd pull the battery 
from the remote.... (I don't know why I'd want to do that.) 

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#446455

On 2/6/2017 1:03 PM, George Herold wrote:
> On Monday, February 6, 2017 at 1:52:22 PM UTC-5, Don Y wrote:
>> On 2/6/2017 10:23 AM, Jeff Liebermann wrote:
>>> On Mon, 6 Feb 2017 00:40:44 -0700, Don Y <blockedofcourse@foo.invalid>
>>> wrote:
>>>
>>>> How can I economically, simply and reversibly inhibit the
>>>> RF link to a GDO?  Short the antenna?  Slip it in a
>>>> grounded copper tube?  etc.

>>> Now, I have a dumb question.  What problem are you trying to solve?
>>
>> I want Joe Average User to be able to cripple the "wireless" activation/control
>> of his opener -- without having to disassemble it *or* consult an exhaustive
>> compilation of "if you have model X, do this" rules.
>>
>> Once crippled -- and until "restored" -- neither his remote nor any OTHER
>> remote should be able to affect the operation of the opener.
>
> Don,  Can I repeat Jeff's question.
>  "Now, I have a dumb question.  What problem are you trying to solve?"

Why does Jim's manufacturer think it is a worthwhile FEATURE to have
included on his unit?  Please ask *them* and get back to us.  I'm
sure we can come up with dozens of reasons why they should have done it
differently -- in complete ignorance of *their* criteria!  But, hey,
second-guessing is FUN, right?  :>

> If I wanted to disable my garage door opener, I'd pull the battery
> from the remote.... (I don't know why I'd want to do that.)

Why not just HIDE the remote?  Let's turn this into a really long thread
in which we posit alternative ways of disabling the *remote* without
altering the *receiver*.  Maybe pot it in a disolvable plastic -- so
we can deencapsulate it when we want to reverse the process?

Or, hire someone to stand on a ladder with the power cord in his hand
and plug/unplug the appliance based on whether or not you want to operate
in any of a VARIETY of different circumstances?!  :>

How about I rephrase my question:
    "How can I economically, simply and reversibly inhibit the
     reception of radio signals by a receiver?"

(Which invites:  What *sort* of receiver?  What frequency band?  What power
level(s)? etc.  I tried to avoid those questions by suggesting a GDO
as representative of the class of devices that are of interest to me)

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#446468

On Monday, February 6, 2017 at 3:31:09 PM UTC-5, Don Y wrote:
> On 2/6/2017 1:03 PM, George Herold wrote:
> > On Monday, February 6, 2017 at 1:52:22 PM UTC-5, Don Y wrote:
> >> On 2/6/2017 10:23 AM, Jeff Liebermann wrote:
> >>> On Mon, 6 Feb 2017 00:40:44 -0700, Don Y <blockedofcourse@foo.invalid>
> >>> wrote:
> >>>
> >>>> How can I economically, simply and reversibly inhibit the
> >>>> RF link to a GDO?  Short the antenna?  Slip it in a
> >>>> grounded copper tube?  etc.
> 
> >>> Now, I have a dumb question.  What problem are you trying to solve?
> >>
> >> I want Joe Average User to be able to cripple the "wireless" activation/control
> >> of his opener -- without having to disassemble it *or* consult an exhaustive
> >> compilation of "if you have model X, do this" rules.
> >>
> >> Once crippled -- and until "restored" -- neither his remote nor any OTHER
> >> remote should be able to affect the operation of the opener.
> >
> > Don,  Can I repeat Jeff's question.
> >  "Now, I have a dumb question.  What problem are you trying to solve?"
> 
> Why does Jim's manufacturer think it is a worthwhile FEATURE to have
> included on his unit?  Please ask *them* and get back to us.  I'm
> sure we can come up with dozens of reasons why they should have done it
> differently -- in complete ignorance of *their* criteria!  But, hey,
> second-guessing is FUN, right?  :>
> 
> > If I wanted to disable my garage door opener, I'd pull the battery
> > from the remote.... (I don't know why I'd want to do that.)
> 
> Why not just HIDE the remote?  Let's turn this into a really long thread
> in which we posit alternative ways of disabling the *remote* without
> altering the *receiver*.  Maybe pot it in a disolvable plastic -- so
> we can deencapsulate it when we want to reverse the process?
> 
> Or, hire someone to stand on a ladder with the power cord in his hand
> and plug/unplug the appliance based on whether or not you want to operate
> in any of a VARIETY of different circumstances?!  :>
> 
> How about I rephrase my question:
>     "How can I economically, simply and reversibly inhibit the
>      reception of radio signals by a receiver?"
> 
> (Which invites:  What *sort* of receiver?  What frequency band?  What power
> level(s)? etc.  I tried to avoid those questions by suggesting a GDO
> as representative of the class of devices that are of interest to me)

Wow.. I'm sensing some hostility Don.  
Is it a one of or something for all GDO's?  
What's wrong with telling the application?  

I've got a colleague, who will come and ask me some very specific question.  
Often when we back out the problem, we'll find a solution that has nothing to 
do with the original question.  

George H. 

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#446470

Den mandag den 6. februar 2017 kl. 22.29.55 UTC+1 skrev George Herold:
> On Monday, February 6, 2017 at 3:31:09 PM UTC-5, Don Y wrote:
> > On 2/6/2017 1:03 PM, George Herold wrote:
> > > On Monday, February 6, 2017 at 1:52:22 PM UTC-5, Don Y wrote:
> > >> On 2/6/2017 10:23 AM, Jeff Liebermann wrote:
> > >>> On Mon, 6 Feb 2017 00:40:44 -0700, Don Y <blockedofcourse@foo.invalid>
> > >>> wrote:
> > >>>
> > >>>> How can I economically, simply and reversibly inhibit the
> > >>>> RF link to a GDO?  Short the antenna?  Slip it in a
> > >>>> grounded copper tube?  etc.
> > 
> > >>> Now, I have a dumb question.  What problem are you trying to solve?
> > >>
> > >> I want Joe Average User to be able to cripple the "wireless" activation/control
> > >> of his opener -- without having to disassemble it *or* consult an exhaustive
> > >> compilation of "if you have model X, do this" rules.
> > >>
> > >> Once crippled -- and until "restored" -- neither his remote nor any OTHER
> > >> remote should be able to affect the operation of the opener.
> > >
> > > Don,  Can I repeat Jeff's question.
> > >  "Now, I have a dumb question.  What problem are you trying to solve?"
> > 
> > Why does Jim's manufacturer think it is a worthwhile FEATURE to have
> > included on his unit?  Please ask *them* and get back to us.  I'm
> > sure we can come up with dozens of reasons why they should have done it
> > differently -- in complete ignorance of *their* criteria!  But, hey,
> > second-guessing is FUN, right?  :>
> > 
> > > If I wanted to disable my garage door opener, I'd pull the battery
> > > from the remote.... (I don't know why I'd want to do that.)
> > 
> > Why not just HIDE the remote?  Let's turn this into a really long thread
> > in which we posit alternative ways of disabling the *remote* without
> > altering the *receiver*.  Maybe pot it in a disolvable plastic -- so
> > we can deencapsulate it when we want to reverse the process?
> > 
> > Or, hire someone to stand on a ladder with the power cord in his hand
> > and plug/unplug the appliance based on whether or not you want to operate
> > in any of a VARIETY of different circumstances?!  :>
> > 
> > How about I rephrase my question:
> >     "How can I economically, simply and reversibly inhibit the
> >      reception of radio signals by a receiver?"
> > 
> > (Which invites:  What *sort* of receiver?  What frequency band?  What power
> > level(s)? etc.  I tried to avoid those questions by suggesting a GDO
> > as representative of the class of devices that are of interest to me)
> 
> Wow.. I'm sensing some hostility Don.  
> Is it a one of or something for all GDO's?  
> What's wrong with telling the application?  
> 
> I've got a colleague, who will come and ask me some very specific question.  
> Often when we back out the problem, we'll find a solution that has nothing to 
> do with the original question.  
> 

http://xyproblem.info/

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#446478

On 2/6/2017 2:29 PM, George Herold wrote:
>> (Which invites:  What *sort* of receiver?  What frequency band?  What power
>> level(s)? etc.  I tried to avoid those questions by suggesting a GDO
>> as representative of the class of devices that are of interest to me)
>
> Wow.. I'm sensing some hostility Don.

Sorry, George.  I'm tired of the "why do you need it" crowd.  Followed by
the "why is this such a long post/thread" comments.

I post in a fair number of online forums and USENET is the only place where
"Why" is the first word out of folks' mouths.  It makes me wonder if they're
all STARVED for intellectual stimulation -- or, simply unable to imagine
problems that don't lie in their immediate areas of expertise.

> Is it a one of or something for all GDO's?

I'm looking for a *technique*.  I can replace GDO with any number of other
wireless devices and present a similar question.  GDO's are just easy examples
to reference with which folks will *probably* have some experience.

Would you prefer I discuss a wirelessly-controller manipulator used in the
manufacture of explosive pellets?  Would you NEED to know the use for those
pellets before answering?

> What's wrong with telling the application?

Because then someone will want to know why I didn't consider THIS
solution or THAT solution.  And, I really don't feel the need
to HAVE TO explain my design choices to someone who is just playing
Monday morning quarterback.

> I've got a colleague, who will come and ask me some very specific question.
> Often when we back out the problem, we'll find a solution that has nothing to
> do with the original question.

 From *my* personal experience, here, I end up being coerced into justifying
every possible decision that I ruled out, then chided for being too "picky".

By folks who weren't able to contribute anything to the solution!

Do you grill your marketing people as to the actual sales projections that
they used to justify a particular feature's inclusion in a new product design?
How happy would you be if THEY came over and grilled you about why you
mounted a particular component in a particular portion of the PCB?  Or,
if your purchasing guy required justification (to satisfy his own personal
curiosity -- perhaps under the guise of "I might be able to find an
alternate/cheaper source") for your selection of a particular component
or vendor?

C'mon, it's a simple question.  I can rewrite it to apply to any number of
wireless products/applications.  And, it doesn't change the nature of the
problem posed!  Or, encumber the presentation in ways that effectively
LIMIT the solution to exactly the area that I've presented.  Would you
then want to examine why each of these constraints were placed on the
problem?  All that just to avoid answering the question asked?

"Mary has 6 apples.  She gives 2 to Dave.  How many apples does Mary have?"

"Why apples?  Why not oranges?  And, what about Bob?  Does Mary hold a grudge 
against Bob?  Why?  Or, is Mary having a fling with Dave?  And, does *Sue*
know???"

Answer:  4.

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#446480

On Mon, 6 Feb 2017 15:01:52 -0700, Don Y <blockedofcourse@foo.invalid>
wrote:

>On 2/6/2017 2:29 PM, George Herold wrote:
>>> (Which invites:  What *sort* of receiver?  What frequency band?  What power
>>> level(s)? etc.  I tried to avoid those questions by suggesting a GDO
>>> as representative of the class of devices that are of interest to me)
>>
>> Wow.. I'm sensing some hostility Don.
>
>Sorry, George.  I'm tired of the "why do you need it" crowd.  Followed by
>the "why is this such a long post/thread" comments.
>
>I post in a fair number of online forums and USENET is the only place where
>"Why" is the first word out of folks' mouths.  It makes me wonder if they're
>all STARVED for intellectual stimulation -- or, simply unable to imagine
>problems that don't lie in their immediate areas of expertise.
>
>> Is it a one of or something for all GDO's?
>
>I'm looking for a *technique*.  I can replace GDO with any number of other
>wireless devices and present a similar question.  GDO's are just easy examples
>to reference with which folks will *probably* have some experience.
>
>Would you prefer I discuss a wirelessly-controller manipulator used in the
>manufacture of explosive pellets?  Would you NEED to know the use for those
>pellets before answering?
>
>> What's wrong with telling the application?
>
>Because then someone will want to know why I didn't consider THIS
>solution or THAT solution.  And, I really don't feel the need
>to HAVE TO explain my design choices to someone who is just playing
>Monday morning quarterback.
>
>> I've got a colleague, who will come and ask me some very specific question.
>> Often when we back out the problem, we'll find a solution that has nothing to
>> do with the original question.
>
> From *my* personal experience, here, I end up being coerced into justifying
>every possible decision that I ruled out, then chided for being too "picky".
>
>By folks who weren't able to contribute anything to the solution!
>
>Do you grill your marketing people as to the actual sales projections that
>they used to justify a particular feature's inclusion in a new product design?
>How happy would you be if THEY came over and grilled you about why you
>mounted a particular component in a particular portion of the PCB?  Or,
>if your purchasing guy required justification (to satisfy his own personal
>curiosity -- perhaps under the guise of "I might be able to find an
>alternate/cheaper source") for your selection of a particular component
>or vendor?
>
>C'mon, it's a simple question.  I can rewrite it to apply to any number of
>wireless products/applications.  And, it doesn't change the nature of the
>problem posed!  Or, encumber the presentation in ways that effectively
>LIMIT the solution to exactly the area that I've presented.  Would you
>then want to examine why each of these constraints were placed on the
>problem?  All that just to avoid answering the question asked?
>
>"Mary has 6 apples.  She gives 2 to Dave.  How many apples does Mary have?"
>
>"Why apples?  Why not oranges?  And, what about Bob?  Does Mary hold a grudge 
>against Bob?  Why?  Or, is Mary having a fling with Dave?  And, does *Sue*
>know???"
>
>Answer:  4.

Cranky!  Cranky!  Will get you nada!
		
                                        ...Jim Thompson
-- 
| James E.Thompson                                 |    mens     |
| Analog Innovations                               |     et      |
| Analog/Mixed-Signal ASIC's and Discrete Systems  |    manus    |
| STV, Queen Creek, AZ 85142    Skype: skypeanalog |             |
| Voice:(480)460-2350  Fax: Available upon request |  Brass Rat  |
| E-mail Icon at http://www.analog-innovations.com |    1962     |

     Thinking outside the box... producing elegant solutions.

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#446482

On 2/6/2017 3:07 PM, Jim Thompson wrote:
> Cranky!  Cranky!  Will get you nada!

Being concise and polite wasn't getting me anything, either!  :>

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#446486

Den mandag den 6. februar 2017 kl. 23.13.20 UTC+1 skrev Don Y:
> On 2/6/2017 3:07 PM, Jim Thompson wrote:
> > Cranky!  Cranky!  Will get you nada!
> 
> Being concise and polite wasn't getting me anything, either!  :>

I doubt anyone ever described you as concise ;)

take it how ever you want but every question you ask seems end the same way, 
you writing walls of text on why every solution proposed is useless 
because it isn't generic enough to cover all previous,current, and future
use cases for all possible manufacturers of possibly yet to be invented 
devices 

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