On Sat, 16 Sep 2023 12:52:55 GMT, Jan Panteltje <alien@comet.invalid>
wrote:
>On a sunny day (Sat, 16 Sep 2023 04:52:06 -0700) it happened John Larkin
><jjlarkin@highlandtechnology.com> wrote in
><rj5bgitnmcvc1n3iu1nfgtufko7djs77rb@4ax.com>:
>
>>On Sat, 16 Sep 2023 05:22:45 GMT, Jan Panteltje <alien@comet.invalid>
>>wrote:
>>
>>>On a sunny day (Fri, 15 Sep 2023 13:51:44 -0700) it happened John Larkin
>>><jjlarkin@highlandtechnology.com> wrote in
>>><7ig9gi5lvb8ho1p4onrtbed451a1ftrmfn@4ax.com>:
>>>
>>>>On Fri, 15 Sep 2023 16:03:44 -0400 (EDT), Martin Rid
>>>><martin_riddle@verison.net> wrote:
>>>>
>>>>>John Larkin <jjlarkin@highlandtechnology.com> Wrote in message:r
>>>>>> On Fri, 15 Sep 2023 12:21:22 -0400 (EDT), Martin Rid<martin_riddle@verison.net> wrote:>Bartolomeo Pestalozzi
>>>>>> <bartolomeopestalozzi65@gmail.com> Wrote in> message:r>> Il giorno venerd� 15 settembre 2023 alle 15:01:44 UTC+2 John
>>>>>> Larkin ha scritto:> On
>>>>>> Fri, 15 Sep 2023 04:57:06 -0700 (PDT), Bartolomeo Pestalozzi > <bartolomeop...@gmail.com> wrote: > > >Hello, > >I am
>>>>>> looking for an
>>>>>> electric schematic of a telephonic Tone and Probe. > > > >Professional instrumet are like this: >
>>>>>> >https://www.fluke.com/en-us/product/network-cable-testers/copper/pro3000f60-kit > >I don't have the pretension nor the
>>>>>> >ambition to make a similar project. >
>>>>>> >I would like to build a simple object to identify the stremity wires. > > > > > > > >Thank you > >Umberto> Amazon has
>>>>>> >wire
>>>>>> tracer kits for around $16. I got one and it's > interesting. You can hear all sorts of e-fields.My purpose was to design
>>>>>> one,
>>>>>> anyway thanks for the indication.>>You can drive a reversed biased diode with a 555 running s a> frequency
>>>>>in the audio band. This will create a nice broad> spectrum modulated hash.>Then use a lm386 audio amp a nd attach the input
>>>>>to
>>>>>a short> antenna probe as the reciever.>I used this setup for many years, and it always works.>>Cheers>CheersThe probe should
>>>>>be
>>>>>very high impedance. Use a jfet or a cmos opampand a lot of resistance to ground.
>>>>>
>>>>>Oh, just a cap to the probe tip. The lm386 has 28db of gain. If
>>>>> it squeals when you touch the probe tip you got gain.
>>>>>
>>>>>
>>>>>Cheers
>>>>
>>>>Yikes. LM386 is an ancient bipolar part with < 50K input impedance.
>>>>Given, say, a 5 pF antenna/probe, the highpass corner frequency is
>>>>about 300 KHz.
>>>>
>>>
>>>I still have some, chip is OK, and still available I think.
>>> https://hackerstore.nl/Artikel/310
>>> say 4 USD for the complete amp, inlcuding volume knob!
>>
>>The 10K pot makes the input impeance even lower, even worse as an
>>e-field probe.
>
>You could always add a JFET or MOSFET, few more cents.
Yes, a jfet or a cmos opamp
You can make a self-biasing jfet amp with just the jfet and a source
resistor to ground. I did that for NASA. It involved rocket tests and
alligators.
Reply by Fred Bloggs●September 16, 20232023-09-16
On Friday, September 15, 2023 at 3:30:34 PM UTC-4, John Larkin wrote:
> On Fri, 15 Sep 2023 12:21:22 -0400 (EDT), Martin Rid
> <martin...@verison.net> wrote:
>
> >Bartolomeo Pestalozzi <bartolomeop...@gmail.com> Wrote in
> > message:r
> >> Il giorno venerdě 15 settembre 2023 alle 15:01:44 UTC+2 John Larkin ha scritto:> On Fri, 15 Sep 2023 04:57:06 -0700 (PDT), Bartolomeo Pestalozzi > <bartolomeop...@gmail.com> wrote: > > >Hello, > >I am looking for an electric schematic of a telephonic Tone and Probe. > > > >Professional instrumet are like this: > >https://www.fluke.com/en-us/product/network-cable-testers/copper/pro3000f60-kit > >I don't have the pretension nor the ambition to make a similar project. > >I would like to build a simple object to identify the stremity wires. > > > > > > > >Thank you > >Umberto> Amazon has wire tracer kits for around $16. I got one and it's > interesting. You can hear all sorts of e-fields.My purpose was to design one, anyway thanks for the indication.
> >
> >You can drive a reversed biased diode with a 555 running s a
> > frequency in the audio band. This will create a nice broad
> > spectrum modulated hash.
> >Then use a lm386 audio amp a nd attach the input to a short
> > antenna probe as the reciever.
> >I used this setup for many years, and it always works.
> >
> >Cheers
> >Cheers
> The probe should be very high impedance. Use a jfet or a cmos opamp
> and a lot of resistance to ground.
I'm starting to lean toward a piezo effect probe. E-field sensors based on a electric field dependent dielectric sandwiched between piezo ceramic plates have been in development for years. Also the piezo is a good way to get very high Q bandpass. It's ultra high-Z all the way. A probe made of this material does have a susceptibility to microphonics- converting vibration to electric.
Reply by Jan Panteltje●September 16, 20232023-09-16
On a sunny day (Sat, 16 Sep 2023 04:52:06 -0700) it happened John Larkin
<jjlarkin@highlandtechnology.com> wrote in
<rj5bgitnmcvc1n3iu1nfgtufko7djs77rb@4ax.com>:
>On Sat, 16 Sep 2023 05:22:45 GMT, Jan Panteltje <alien@comet.invalid>
>wrote:
>
>>On a sunny day (Fri, 15 Sep 2023 13:51:44 -0700) it happened John Larkin
>><jjlarkin@highlandtechnology.com> wrote in
>><7ig9gi5lvb8ho1p4onrtbed451a1ftrmfn@4ax.com>:
>>
>>>On Fri, 15 Sep 2023 16:03:44 -0400 (EDT), Martin Rid
>>><martin_riddle@verison.net> wrote:
>>>
>>>>John Larkin <jjlarkin@highlandtechnology.com> Wrote in message:r
>>>>> On Fri, 15 Sep 2023 12:21:22 -0400 (EDT), Martin Rid<martin_riddle@verison.net> wrote:>Bartolomeo Pestalozzi
>>>>> <bartolomeopestalozzi65@gmail.com> Wrote in> message:r>> Il giorno venerd� 15 settembre 2023 alle 15:01:44 UTC+2 John
>>>>> Larkin ha scritto:> On
>>>>> Fri, 15 Sep 2023 04:57:06 -0700 (PDT), Bartolomeo Pestalozzi > <bartolomeop...@gmail.com> wrote: > > >Hello, > >I am
>>>>> looking for an
>>>>> electric schematic of a telephonic Tone and Probe. > > > >Professional instrumet are like this: >
>>>>> >https://www.fluke.com/en-us/product/network-cable-testers/copper/pro3000f60-kit > >I don't have the pretension nor the
>>>>> >ambition to make a similar project. >
>>>>> >I would like to build a simple object to identify the stremity wires. > > > > > > > >Thank you > >Umberto> Amazon has
>>>>> >wire
>>>>> tracer kits for around $16. I got one and it's > interesting. You can hear all sorts of e-fields.My purpose was to design
>>>>> one,
>>>>> anyway thanks for the indication.>>You can drive a reversed biased diode with a 555 running s a> frequency
>>>>in the audio band. This will create a nice broad> spectrum modulated hash.>Then use a lm386 audio amp a nd attach the input
>>>>to
>>>>a short> antenna probe as the reciever.>I used this setup for many years, and it always works.>>Cheers>CheersThe probe should
>>>>be
>>>>very high impedance. Use a jfet or a cmos opampand a lot of resistance to ground.
>>>>
>>>>Oh, just a cap to the probe tip. The lm386 has 28db of gain. If
>>>> it squeals when you touch the probe tip you got gain.
>>>>
>>>>
>>>>Cheers
>>>
>>>Yikes. LM386 is an ancient bipolar part with < 50K input impedance.
>>>Given, say, a 5 pF antenna/probe, the highpass corner frequency is
>>>about 300 KHz.
>>>
>>
>>I still have some, chip is OK, and still available I think.
>> https://hackerstore.nl/Artikel/310
>> say 4 USD for the complete amp, inlcuding volume knob!
>
>The 10K pot makes the input impeance even lower, even worse as an
>e-field probe.
You could always add a JFET or MOSFET, few more cents.
Reply by John Larkin●September 16, 20232023-09-16
On Sat, 16 Sep 2023 05:22:45 GMT, Jan Panteltje <alien@comet.invalid>
wrote:
>On a sunny day (Fri, 15 Sep 2023 13:51:44 -0700) it happened John Larkin
><jjlarkin@highlandtechnology.com> wrote in
><7ig9gi5lvb8ho1p4onrtbed451a1ftrmfn@4ax.com>:
>
>>On Fri, 15 Sep 2023 16:03:44 -0400 (EDT), Martin Rid
>><martin_riddle@verison.net> wrote:
>>
>>>John Larkin <jjlarkin@highlandtechnology.com> Wrote in message:r
>>>> On Fri, 15 Sep 2023 12:21:22 -0400 (EDT), Martin Rid<martin_riddle@verison.net> wrote:>Bartolomeo Pestalozzi
>>>> <bartolomeopestalozzi65@gmail.com> Wrote in> message:r>> Il giorno venerd� 15 settembre 2023 alle 15:01:44 UTC+2 John Larkin ha scritto:> On
>>>> Fri, 15 Sep 2023 04:57:06 -0700 (PDT), Bartolomeo Pestalozzi > <bartolomeop...@gmail.com> wrote: > > >Hello, > >I am looking for an
>>>> electric schematic of a telephonic Tone and Probe. > > > >Professional instrumet are like this: >
>>>> >https://www.fluke.com/en-us/product/network-cable-testers/copper/pro3000f60-kit > >I don't have the pretension nor the ambition to make a similar project. >
>>>> >I would like to build a simple object to identify the stremity wires. > > > > > > > >Thank you > >Umberto> Amazon has wire
>>>> tracer kits for around $16. I got one and it's > interesting. You can hear all sorts of e-fields.My purpose was to design one,
>>>> anyway thanks for the indication.>>You can drive a reversed biased diode with a 555 running s a> frequency
>>>in the audio band. This will create a nice broad> spectrum modulated hash.>Then use a lm386 audio amp a nd attach the input to
>>>a short> antenna probe as the reciever.>I used this setup for many years, and it always works.>>Cheers>CheersThe probe should be
>>>very high impedance. Use a jfet or a cmos opampand a lot of resistance to ground.
>>>
>>>Oh, just a cap to the probe tip. The lm386 has 28db of gain. If
>>> it squeals when you touch the probe tip you got gain.
>>>
>>>
>>>Cheers
>>
>>Yikes. LM386 is an ancient bipolar part with < 50K input impedance.
>>Given, say, a 5 pF antenna/probe, the highpass corner frequency is
>>about 300 KHz.
>>
>
>I still have some, chip is OK, and still available I think.
> https://hackerstore.nl/Artikel/310
> say 4 USD for the complete amp, inlcuding volume knob!
The 10K pot makes the input impeance even lower, even worse as an
e-field probe.
Reply by Jan Panteltje●September 16, 20232023-09-16
On a sunny day (Fri, 15 Sep 2023 13:51:44 -0700) it happened John Larkin
<jjlarkin@highlandtechnology.com> wrote in
<7ig9gi5lvb8ho1p4onrtbed451a1ftrmfn@4ax.com>:
>On Fri, 15 Sep 2023 16:03:44 -0400 (EDT), Martin Rid
><martin_riddle@verison.net> wrote:
>
>>John Larkin <jjlarkin@highlandtechnology.com> Wrote in message:r
>>> On Fri, 15 Sep 2023 12:21:22 -0400 (EDT), Martin Rid<martin_riddle@verison.net> wrote:>Bartolomeo Pestalozzi
>>> <bartolomeopestalozzi65@gmail.com> Wrote in> message:r>> Il giorno venerd� 15 settembre 2023 alle 15:01:44 UTC+2 John Larkin ha scritto:> On
>>> Fri, 15 Sep 2023 04:57:06 -0700 (PDT), Bartolomeo Pestalozzi > <bartolomeop...@gmail.com> wrote: > > >Hello, > >I am looking for an
>>> electric schematic of a telephonic Tone and Probe. > > > >Professional instrumet are like this: >
>>> >https://www.fluke.com/en-us/product/network-cable-testers/copper/pro3000f60-kit > >I don't have the pretension nor the ambition to make a similar project. >
>>> >I would like to build a simple object to identify the stremity wires. > > > > > > > >Thank you > >Umberto> Amazon has wire
>>> tracer kits for around $16. I got one and it's > interesting. You can hear all sorts of e-fields.My purpose was to design one,
>>> anyway thanks for the indication.>>You can drive a reversed biased diode with a 555 running s a> frequency
>>in the audio band. This will create a nice broad> spectrum modulated hash.>Then use a lm386 audio amp a nd attach the input to
>>a short> antenna probe as the reciever.>I used this setup for many years, and it always works.>>Cheers>CheersThe probe should be
>>very high impedance. Use a jfet or a cmos opampand a lot of resistance to ground.
>>
>>Oh, just a cap to the probe tip. The lm386 has 28db of gain. If
>> it squeals when you touch the probe tip you got gain.
>>
>>
>>Cheers
>
>Yikes. LM386 is an ancient bipolar part with < 50K input impedance.
>Given, say, a 5 pF antenna/probe, the highpass corner frequency is
>about 300 KHz.
>
I still have some, chip is OK, and still available I think.
https://hackerstore.nl/Artikel/310
say 4 USD for the complete amp, inlcuding volume knob!
Reply by Fred Bloggs●September 15, 20232023-09-15
On Friday, September 15, 2023 at 3:30:34 PM UTC-4, John Larkin wrote:
> On Fri, 15 Sep 2023 12:21:22 -0400 (EDT), Martin Rid
> <martin...@verison.net> wrote:
>
> >Bartolomeo Pestalozzi <bartolomeop...@gmail.com> Wrote in
> > message:r
> >> Il giorno venerdě 15 settembre 2023 alle 15:01:44 UTC+2 John Larkin ha scritto:> On Fri, 15 Sep 2023 04:57:06 -0700 (PDT), Bartolomeo Pestalozzi > <bartolomeop...@gmail.com> wrote: > > >Hello, > >I am looking for an electric schematic of a telephonic Tone and Probe. > > > >Professional instrumet are like this: > >https://www.fluke.com/en-us/product/network-cable-testers/copper/pro3000f60-kit > >I don't have the pretension nor the ambition to make a similar project. > >I would like to build a simple object to identify the stremity wires. > > > > > > > >Thank you > >Umberto> Amazon has wire tracer kits for around $16. I got one and it's > interesting. You can hear all sorts of e-fields.My purpose was to design one, anyway thanks for the indication.
> >
> >You can drive a reversed biased diode with a 555 running s a
> > frequency in the audio band. This will create a nice broad
> > spectrum modulated hash.
> >Then use a lm386 audio amp a nd attach the input to a short
> > antenna probe as the reciever.
> >I used this setup for many years, and it always works.
> >
> >Cheers
> >Cheers
> The probe should be very high impedance. Use a jfet or a cmos opamp
> and a lot of resistance to ground.
On Friday, September 15, 2023 at 3:30:34 PM UTC-4, John Larkin wrote:
> On Fri, 15 Sep 2023 12:21:22 -0400 (EDT), Martin Rid
> <martin...@verison.net> wrote:
>
> >Bartolomeo Pestalozzi <bartolomeop...@gmail.com> Wrote in
> > message:r
> >> Il giorno venerdě 15 settembre 2023 alle 15:01:44 UTC+2 John Larkin ha scritto:> On Fri, 15 Sep 2023 04:57:06 -0700 (PDT), Bartolomeo Pestalozzi > <bartolomeop...@gmail.com> wrote: > > >Hello, > >I am looking for an electric schematic of a telephonic Tone and Probe. > > > >Professional instrumet are like this: > >https://www.fluke.com/en-us/product/network-cable-testers/copper/pro3000f60-kit > >I don't have the pretension nor the ambition to make a similar project. > >I would like to build a simple object to identify the stremity wires. > > > > > > > >Thank you > >Umberto> Amazon has wire tracer kits for around $16. I got one and it's > interesting. You can hear all sorts of e-fields.My purpose was to design one, anyway thanks for the indication.
> >
> >You can drive a reversed biased diode with a 555 running s a
> > frequency in the audio band. This will create a nice broad
> > spectrum modulated hash.
> >Then use a lm386 audio amp a nd attach the input to a short
> > antenna probe as the reciever.
> >I used this setup for many years, and it always works.
> >
> >Cheers
> >Cheers
> The probe should be very high impedance. Use a jfet or a cmos opamp
> and a lot of resistance to ground.
It's obviously a directional E-field probe working strictly with coupling capacitance. The probe tip, pickup, is oriented perpendicularly to infinite line of charge and connects to a circuit in an insulated probe case. The capacitance between the circuit common, of what has to be a high impedance transconductance preamp, and the user's body and back to the infinite line cable completes the circuit. The probe tip geometry must be the best they could do cheaply to create the greatest sensitivity of probe orientation relative to the cable. My guess is they're working with a charge amplifier. And there's something up with probe tip geometry that creates a very rapid rolloff for frequencies below 1kHz.
Note they state this works on lines up to 10 miles length. The cheap amazon stuff is stretching it to make 1000 ft, and the positional discrimination between cables probably isn't very good.
Reply by John Larkin●September 15, 20232023-09-15
On Fri, 15 Sep 2023 16:03:44 -0400 (EDT), Martin Rid
<martin_riddle@verison.net> wrote:
>John Larkin <jjlarkin@highlandtechnology.com> Wrote in message:r
>> On Fri, 15 Sep 2023 12:21:22 -0400 (EDT), Martin Rid<martin_riddle@verison.net> wrote:>Bartolomeo Pestalozzi <bartolomeopestalozzi65@gmail.com> Wrote in> message:r>> Il giorno venerd� 15 settembre 2023 alle 15:01:44 UTC+2 John Larkin ha scritto:> On Fri, 15 Sep 2023 04:57:06 -0700 (PDT), Bartolomeo Pestalozzi > <bartolomeop...@gmail.com> wrote: > > >Hello, > >I am looking for an electric schematic of a telephonic Tone and Probe. > > > >Professional instrumet are like this: > >https://www.fluke.com/en-us/product/network-cable-testers/copper/pro3000f60-kit > >I don't have the pretension nor the ambition to make a similar project. > >I would like to build a simple object to identify the stremity wires. > > > > > > > >Thank you > >Umberto> Amazon has wire tracer kits for around $16. I got one and it's > interesting. You can hear all sorts of e-fields.My purpose was to design one, anyway thanks for the indication.>>You can drive a reversed biased diode with a 555 running s a> frequency
>in the audio band. This will create a nice broad> spectrum modulated hash.>Then use a lm386 audio amp a nd attach the input to a short> antenna probe as the reciever.>I used this setup for many years, and it always works.>>Cheers>CheersThe probe should be very high impedance. Use a jfet or a cmos opampand a lot of resistance to ground.
>
>Oh, just a cap to the probe tip. The lm386 has 28db of gain. If
> it squeals when you touch the probe tip you got gain.
>
>
>Cheers
Yikes. LM386 is an ancient bipolar part with < 50K input impedance.
Given, say, a 5 pF antenna/probe, the highpass corner frequency is
about 300 KHz.
Reply by Martin Rid●September 15, 20232023-09-15
John Larkin <jjlarkin@highlandtechnology.com> Wrote in message:r
> On Fri, 15 Sep 2023 12:21:22 -0400 (EDT), Martin Rid<martin_riddle@verison.net> wrote:>Bartolomeo Pestalozzi <bartolomeopestalozzi65@gmail.com> Wrote in> message:r>> Il giorno venerd� 15 settembre 2023 alle 15:01:44 UTC+2 John Larkin ha scritto:> On Fri, 15 Sep 2023 04:57:06 -0700 (PDT), Bartolomeo Pestalozzi > <bartolomeop...@gmail.com> wrote: > > >Hello, > >I am looking for an electric schematic of a telephonic Tone and Probe. > > > >Professional instrumet are like this: > >https://www.fluke.com/en-us/product/network-cable-testers/copper/pro3000f60-kit > >I don't have the pretension nor the ambition to make a similar project. > >I would like to build a simple object to identify the stremity wires. > > > > > > > >Thank you > >Umberto> Amazon has wire tracer kits for around $16. I got one and it's > interesting. You can hear all sorts of e-fields.My purpose was to design one, anyway thanks for the indication.>>You can drive a reversed biased diode with a 555 running s a> frequency in the audio band. This will create a nice broad> spectrum modulated hash.>Then use a lm386 audio amp a nd attach the input to a short> antenna probe as the reciever.>I used this setup for many years, and it always works.>>Cheers>CheersThe probe should be very high impedance. Use a jfet or a cmos opampand a lot of resistance to ground.
On Fri, 15 Sep 2023 12:21:22 -0400 (EDT), Martin Rid
<martin_riddle@verison.net> wrote:
>Bartolomeo Pestalozzi <bartolomeopestalozzi65@gmail.com> Wrote in
> message:r
>> Il giorno venerd� 15 settembre 2023 alle 15:01:44 UTC+2 John Larkin ha scritto:> On Fri, 15 Sep 2023 04:57:06 -0700 (PDT), Bartolomeo Pestalozzi > <bartolomeop...@gmail.com> wrote: > > >Hello, > >I am looking for an electric schematic of a telephonic Tone and Probe. > > > >Professional instrumet are like this: > >https://www.fluke.com/en-us/product/network-cable-testers/copper/pro3000f60-kit > >I don't have the pretension nor the ambition to make a similar project. > >I would like to build a simple object to identify the stremity wires. > > > > > > > >Thank you > >Umberto> Amazon has wire tracer kits for around $16. I got one and it's > interesting. You can hear all sorts of e-fields.My purpose was to design one, anyway thanks for the indication.
>
>You can drive a reversed biased diode with a 555 running s a
> frequency in the audio band. This will create a nice broad
> spectrum modulated hash.
>Then use a lm386 audio amp a nd attach the input to a short
> antenna probe as the reciever.
>I used this setup for many years, and it always works.
>
>Cheers
>Cheers
The probe should be very high impedance. Use a jfet or a cmos opamp
and a lot of resistance to ground.