Phone receivers & 9 volt battery

[jmellc]

This goes back a ways, probably only geezers like me will remember.

Back in the 70's, a few people I worked with made up telephone handsets to talk during long wire pulls, also used them to ring out wires in a conduit if markers had come off. One receiver had a 9 volt battery taped to it and 2 leads with alligator clips. Other receiver just had the 2 leads. For talking, a roll of bell wire was usually stretched between pull points. For ringing out, one party clipped to the conduit and 1 wire. Other party clipped to conduit and tried 1 wire at a time until they connected.

Very old school in today's world but I could still use such a setup in a few situations. We all have smart phones now but we can run batteries down and don't always get good reception in some buildings. Would be especially good for ringing out.

Does anyone recall how these were wired?

 

[GoldDigger]

Battery and both receivers in series. The phone handsets will be on the order of several hundred ohms. If separate leads are accessible for mike and speaker in handset, again put them in series.

 

[LarryFine]

Old phone microphones used carbon particles to turn sound waves into a varying resistance, requiring a DC power source. The field usage you described had everything in a single series loop, so both parties heard both voices.

Modern microphones emit small electrical signals that must be amplified, requiring electronics and a power supply. Your best bet would be to try to acquire a couple of old-fashion telephones or at least the handsets from them.

 

[gaelectric]

I still have a set of these. Haven't used them since Nextel. Used to use them to ring out sub feeds on multi family when no one wanted to mark the cables.

 

[Hv&Lv]

This goes back a ways, probably only geezers like me will remember.

Back in the 70's, a few people I worked with made up telephone handsets to talk during long wire pulls, also used them to ring out wires in a conduit if markers had come off. One receiver had a 9 volt battery taped to it and 2 leads with alligator clips. Other receiver just had the 2 leads. For talking, a roll of bell wire was usually stretched between pull points. For ringing out, one party clipped to the conduit and 1 wire. Other party clipped to conduit and tried 1 wire at a time until they connected.

Very old school in today's world but I could still use such a setup in a few situations. We all have smart phones now but we can run batteries down and don't always get good reception in some buildings. Would be especially good for ringing out.

Does anyone recall how these were wired?

Can’t believe these are still available...

https://www.amazon.com/Tracer-Electr.../dp/B003TNDMWI

 

[jmellc]

Can’t believe these are still available...

https://www.amazon.com/Tracer-Electr.../dp/B003TNDMWI

I never knew any were factory made like that. All the ones I saw were homemade. One guy always ahead of the crowd made a set with headphones.

 

[hbiss]

I never knew any were factory made like that. All the ones I saw were homemade. One guy always ahead of the crowd made a set with headphones.

That's because back then you could find phones lying around everywhere that used a carbon transmitter and dynamic receiver, already wired in series. All you needed was two and a battery.

Us old phone guys used our butt sets along with one of our toners which provided talk battery.

-Hal

 

[zbang]

Modern microphones emit small electrical signals that must be amplified, requiring electronics and a power supply. Your best bet would be to try to acquire a couple of old-fashion telephones or at least the handsets from them.

Any POTS telephone should work, just not necessarily the handset on it's own. Get two cheap phones and put them in series with the battery. POTS phones are usually connected in parallel, but the normal telco feed circuit isolates the source from the line; without it, the battery soaks up all the voice signal.

There's a short explanation w/ feed circuit at http://oldphoneguy.com/BatFeedGO.htm and a much longer one here http://www.epanorama.net/circuits/teleinterface.html.

z! (who still considers the butt set and toner to be essential troubleshooting tools)