System Test Set 139B
System AT-8629 Banana Test Probe
77HP Toner "The Tracer"
When working with phone wiring it's common that there are a number of pairs and you want to know which one connects to a line or phone. Putting a tone on the line in question and then seeing which pair carries the tone is a good way to do this. But that would require spending a lot of time connecting a but set to all the possible pairs and if there were a hundred pairs that could take some time. So, by using a non contact probe the time to find the pair with tone can be accomplished in seconds.
Described in BSP 105-242-100 (2 Nov 1974).
Uses 2 AA batteries.
Note: When tone is applied to the two wires of a pair the twist works to minimize radiation of the tone. To maximize tone strength for use with test probes it's best to apply to one wire of a pair and something other than the other side of the same pair (such as ground, other pairs etc.).
- Line Verification w/Butt Set
- Pair ID w/AT-8629 & Butt Set
- Short Detection w/Butt Set
- Open Wire Detection w/AT-8629 & Butt Set
- Tracing Station Wire w/AT-8629 & Butt Set
- Grounded Conductor Test w/Butt Set
- Cross Test w/Butt Set
- Split Pair Test w/AT-8629 & Butt Set
- Continuity Test w/Butt Set
- Buried Service Wire ID w/AT-8629 & Butt Set
- Talk Battery w/2 phones or Butt Sets
Use KS14368 or Equivalent 1.5V Batteries.
CAUTION: See BSP-105-242-100 on use of Alkaline Batteries.
Described in BSP 105-241-100 (5 Jan 1976).
Uses 206 cylindrical 9 Volt battery (Equivalent to: Mallory TR-126, NEDA 1611, H-7D, H-6D 50.8 x 18.6 mm)
The probe requires a tone source in the range of 500 to 1200 Hz such as 76-type, KS-16900, 81A, 139A, 145A or a central office 1000 Hz tone. The tone can be applied at the CO or locally.
AT-8629 Banana Probe
Dead 206 9 Volt cylindrical battery. Equivalent to: Mallory TR-126, NEDA 1611, H-7D, H-6D 50.8 x 18.6 mm
It may be that a stack of 625 button cells will work to replace this obsolete battery. On order 24 Sep 2013 . .
Printed Circuit Board pushed out of metal cylinder (black wire broken)
This is a capacitive input high impedance probe.
This is a modern and smaller version of the Bell System 139B, but without all the test capabilities of the 139B.
Uses standard 9 V battery.
This inductive tone probe has a self contained speaker and volume control. Push to turn on, release to turn off button.
At the top there are a couple of terminals in parallel with the speaker wiring to allow connecting a handset.
This probe will detect 60 Hz AC mains hum.
Page created 13 Sep 2013.