3M Inductive Tone Probe - UK Vintage Radio Repair and Restoration Discussion Forum

Chaparal · 12th Mar 2011, 4:00 pm

Hi,

i'm looking for some info about a 3M Inductive Tone Probe

from 3M Telecom Systems,

used for APICS (PCM) field units ?

Assy no XE-1014-7617-6 / CE-1006-7740-6

The pen is 185mm long, 10mm diameter, cord and has a 6.3mm connector

Inside the connector is a 3 wire cable (2+GND) connected
and should be connected to a (LF) receiver (33Khz ??).

The pen is closed and has metal top (test pin)

My question is, what is inside ?

Only a transformer, an amplifier, is external power needed

I don't want to open it.

Maybe someone has used such a probe ?

pic attached

thanks
Peter

Chaparal · 28th Mar 2011, 1:43 am

Some more info,

i opened the shielded probe case.

Inside is PCB with a N-Fet (max 100 MHz) high impedance (10Meg) transistor Amp. stage, open drain, with possible utility voltage 15V.
The remaining/missing circuit is in the test equipment, i think.
Used working frequency appr. 30 MHz

How looks the missing circuit ?
For what else can the probe be used ?
Maybe input Amp for a selective voltmeter ?

Peter

12th Mar 2011, 4:00 pm	#1
Chaparal Hexode Join Date: Apr 2007 Location: Wiesbaden, Germany Posts: 333	3M Inductive Tone Probe Hi, i'm looking for some info about a 3M Inductive Tone Probe from 3M Telecom Systems, used for APICS (PCM) field units ? Assy no XE-1014-7617-6 / CE-1006-7740-6 The pen is 185mm long, 10mm diameter, cord and has a 6.3mm connector Inside the connector is a 3 wire cable (2+GND) connected and should be connected to a (LF) receiver (33Khz ??). The pen is closed and has metal top (test pin) My question is, what is inside ? Only a transformer, an amplifier, is external power needed I don't want to open it. Maybe someone has used such a probe ? pic attached thanks Peter Attached Thumbnails

28th Mar 2011, 1:43 am	#2
Chaparal Hexode Join Date: Apr 2007 Location: Wiesbaden, Germany Posts: 333	Re: 3M Inductive Tone Probe Some more info, i opened the shielded probe case. Inside is PCB with a N-Fet (max 100 MHz) high impedance (10Meg) transistor Amp. stage, open drain, with possible utility voltage 15V. The remaining/missing circuit is in the test equipment, i think. Used working frequency appr. 30 MHz How looks the missing circuit ? For what else can the probe be used ? Maybe input Amp for a selective voltmeter ? Peter Attached Thumbnails