Electronics-Related.com
Forums

telephonic Tone and Probe schematic

Started by Bartolomeo Pestalozzi September 15, 2023
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
On Fri, 15 Sep 2023 04:57:06 -0700 (PDT), Bartolomeo Pestalozzi
<bartolomeopestalozzi65@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.
Il giorno venerd&igrave; 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.
Bartolomeo Pestalozzi <bartolomeopestalozzi65@gmail.com> Wrote in
 message:r
> Il giorno venerd&#4294967295; 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 -- ----Android NewsGroup Reader---- https://piaohong.s3-us-west-2.amazonaws.com/usenet/index.html
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&#4294967295; 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.
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&#4294967295; 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 -- ----Android NewsGroup Reader---- https://piaohong.s3-us-west-2.amazonaws.com/usenet/index.html
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&#4294967295; 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.
On Friday, September 15, 2023 at 3:30:34&#8239;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 venerd&#283; 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.
On Friday, September 15, 2023 at 3:30:34&#8239;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 venerd&#283; 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.
Almost forgot. Brief 300 page treatise on calculating capacitance to the nth degree: https://apps.dtic.mil/sti/tr/pdf/AD0727198.pdf
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&#4294967295; 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!