new member requests help

[Sligichan]

Have been setting up local-battery system with magneto sets between buildings on my property and hope folks can help with some  questions--
1).  have a WE 202 with  handset with older bullet-type transmitter.  The voice coming to other receivers is very muffled.  Any suggestions on enhancing transmitter or is consensus that this type is just not very good and should replace with F1 unit.  Are adapters to allow this conversion readily available?

2)Have a Northern Electric  N1417CG which when I set it up on a 'test-stand' with several other phones, the ringer functioned normally.  Now when I have the NE set in the local-battery circuit the ringer will not function when any other magneto is activated.  When I crank the magneto of this NE set, all the other phones ring (but not the NE when cranked).  The talk circuit works fine but I cannot know when  a call is coming through on this set as the ringer will not work from any other magneto.
3). I have a Leich set which seems closest to the diagram for a 315H subscriber set with 211A-3 handset.  Again similar to the NE set, when the magneto is cranked all the other sets ring (but again not the NE set).  And when any other magneto is cranked this Leich  ringer will not respond.

I checked all the magnetos before putting the sets on the circuit and they all put out 60-90+ volts when cranked.

So, all my talking circuits work fine in this local-battery setup but some sets have problem with ringers via magnetos.

Wonder if you folks have any suggestions.

Thanks

[dsk]

Welcome Sligichan

Regarding the transmitter, i don't know. Generally some carefully knocking and rolling may loose up clogged carbon, and solve the problem.

Some magneto telephones don't ring their own ringer when cranked. It should ring when another phone is cranked.

dsk

[poplar1]

The 395B (bullet) transmitters are usually bad, though as dsk said, tapping them may loosen the packed carbon granules. Starting in 1935, they used 625A transmitters with F-1 transmitter units on all new handsets and also on remanufactured old ones. However, the F-1 won't fit in the old 395B aluminum base without extensive altering. It would be much easier to find a complete 625A transmitter (base, F-1 unit, and grid). The snuff catcher from the 395B can be reused with the 625A.

[Sligichan]

Follow up on request--Discovered there was voltage on the line when all phones ON-hook and that was preventing magneto signaling.    My battery supply of 6v would fail after a few days as it was acting as though the talk-circuit was always on when actually all the phones were ON-hook and there should not have been any significant voltage on the line at that point. Traced to one phone and when that was disconnected,  all the others on my system functioned normally both talk circuit and magneto ring-signaling and when those phones were ON-hook there was none or perhaps 0.03v across line 1 and 2.  My problem phone appears to be my Northern Electric N1417CG.

Have studied the wiring diagram from the TCI Library site.  Here are some measurements I took and wonder if anyone can suggest source of problem----

When the battery supply is connected to this NE phone there is scratching noise in the receiver even though it is ON-hook.  Can understand this would happen if phone OFF-hook but it is happening when ON-hook.

ON-hook and battery connected there is 5.4v across line 1 and 2 but when key button is depressed, voltage drops to 0.03v.

voltage across the battery connections, ON-hook = 6.2v / OFF-hook = 4.0v

voltage across battery and line 1 --OFF-hook = 0.8v / ON-hook = 0.6v
voltage across battery and line 2-- OFF-hook = 6.0v / ON-hook = 6.0v


On the wiring diagram there is a resistor between connections B and BK and it is in place and  I measure it at 190 ohms.  The diagram also shows a resistor(??within induction coil, but not obvious to me) between points S2 and S3 connecting respectively to points D and B but I don't find where this is on my phone.  There is also indicated to be an induction device between points P and P connecting to Battery and BK.  Wonder if this is all contained within the one induction coil but still wonder where the resistance element is contained.

The diagram also shows a 149F condenser (in hatched-lines) going to connection D.  Wonder if this is part of a standard plain magneto system and thus should be attached.  Does anyone know microfarads of this #149F and if it should be in the circuit? The other condenser labeled #149E is in place going to the two connections labeled COND.

Would appreciate any help folks can offer.  Thanks

[poplar1]

This doesn't answer your questions, but perhaps it will show you the basic "local battery" circuit--that is, one where the battery and generator are at each subscriber's location.

Link:

http://www.telephonecollectors.info/index.php/document-repository/doc_details/2262-magneto-telephones-we317-tl


One path, when the receiver is off the hook, is as follows:

The transmitter, battery, primary winding of the induction coil (P and P), and hookswitch are in series. There should not be any current flow through the batteries until the hookswitch contacts close. The battery is needed only for transmitting if I understand this correctly. So, other than the transmitter, the phone would still function without any batteries in your phone--the generator to signal others, the ringer, and the receiver would still work. Your receiver is powered by the batteries in other people's phones or by the batteries in the operator's talk circuit at the central switchboard.

The receiver is not connected to the battery. Rather it operates on Alternating Current induced in the secondary winding of the induction coil (Terminals S and S).

Please correct me if this analysis is not accurate. I haven't thought about it much since we were kids with hand generators and batteries for an intercom between two houses, with two tree-houses connected in between.

[Sligichan]

Poplar,

Thanks for feedback, but still cannot understand why this NE phone has full voltage across LINE 1 and 2 when the receiver is ON-hook and thus the big problem of battery getting  depleted in a few days.  None of the other phones on my system (five phones) have any voltage across the LINE connectors when  handset or receiver ON-hook.  OFF-hook voltage for the other five phones is present as would expect for talking circuit and then absent when back ON-hook.  This NE phone is leaking current somewhere but I cannot determine where.

[poplar1]

Is there continuity between the Green and Slate hookswitch wires when the phone is hung up?

http://www.telephonecollectors.info/index.php/document-repository/doc_details/2007-magneto-telephone-sets-ne1417ah-f-cg-ap-and-bp-ne1417-tl

[G-Man]

There absolutely should not be any voltage across L1 and L2 unless both the hookswitch and 149E condenser are faulty or if someone has miswired this instrument.

Start by inspecting the hookswitch contacts and then lifting one lead of the 149E condenser to see if the voltage is removed from across the line.

You  are not by any chance trying to use a common battery for all of your magnetos sets, are you?

[G-Man]

The diagram also shows a 149F condenser (in hatched-lines) going to connection D. Wonder if this is part of a standard plain magneto system and thus should be attached. Does anyone know microfarads of this #149F and if it should be in the circuit? The other condenser labeled #149E is in place going to the two connections labeled COND.

The 149F condenser and 63-type resistor were connected in various combinations to terminals D, B, and BK to provide for the equalization and sidetone reduction different lengths of open-wire.

149F Condenser = .65uf         
149E Condenser = 1.0uf

[Sligichan]

Poplar1 & G-man,

Thanks for input and I will check the hookswitch wiring as suggested.

As for my battery source, I do in one sense have a "common" battery--to avoid having a separate battery at each phone and because I had plenty of spare wires (using cat-5e cable), I backwired via a separate twisted-pair to each phone's battery input from one  centrally located battery. So each phone has two twisted-pairs  connected, one to connect LINE 1 and 2 for talking and magneto ringing and one to deliver the 6v to the battery connections.

[G-Man]

Using a common battery for multiple local battery telephones, especially with mixed models is asking for problems.

Temporarily disconnect the "common battery" from the 1417CG and connect a separate battery such as two flashlight cells in series and see if this cures your problem. If not we can troubleshoot further.

[Sligichan]

G-Man,

Thanks for input, I will try your suggestion as soon as I get home.

For my education, what is the problem with a "common" battery coming to each phone via separate wiring to each phones' BATT connections? Common sense would tell me 6v from a battery two inches from each BATT connection or 6v. from two hundred feet from each phones' BATT connections should be equivalent. I measured the voltage on each of my phones with this "common" battery setup and each phone's BATT connection measures about the same 6v.   And yes, I am using a mix of phones by different manufacturers--NE, WE, Leich. So I guess my version of common sense might be faulty...appreciate reading your take on this?

[rdelius]

When I used a common battery type power supply to supply talk battery, I had do insert additional impedence in series ti keep from shorting out the power supply with the low resistance talking path

[poplar1]

When I used a common battery type power supply to supply talk battery, I had do insert additional impedence in series ti keep from shorting out the power supply with the low resistance talking path

Choke coil?

[unbeldi]

G-Man,

Thanks for input, I will try your suggestion as soon as I get home.

For my education, what is the problem with a "common" battery coming to each phone via separate wiring to each phones' BATT connections? Common sense would tell me 6v from a battery two inches from each BATT connection or 6v. from two hundred feet from each phones' BATT connections should be equivalent. I measured the voltage on each of my phones with this "common" battery setup and each phone's BATT connection measures about the same 6v.   And yes, I am using a mix of phones by different manufacturers--NE, WE, Leich. So I guess my version of common sense might be faulty...appreciate reading your take on this?

The battery of a transmitter speech circuit is not just a passive element supplying operating current, as if you hooked up multiple lamps to the same supply, which essentially just waste the input energy.  The dynamic speech signal, a variable frequency AC, is flowing through the battery too and if you have multiple transmitters powered, you need do have some kind of impedance block, i.e. an isolation circuit, to prevent the multiple transmitter circuits from interacting.

Look for example at a diagram of a connection through a common battery central office to see how the speech circuits of the two local loops are isolated from the battery.

You should not call this a "common battery" circuit, that term is well-understood as a specific configuration in telephony.  You may call it a "shared battery" by your design.

Why don't you just draw a circuit diagram of your telephone set? Trace all wires between the components, and draw it out on paper.  The problem should reveal itself almost automatically. Perhaps the phone is miswired, perhaps the hookswitch does not break the circuit when on-hook.