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Northern No. 1 Mahogany Brown

Started by wds, June 23, 2015, 06:37:20 PM

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unbeldi

Quote from: Ktownphoneco on August 25, 2015, 07:13:15 PM
As Dave has stated, no patent dates visible.    Attached are comparison photos of a Western 101-A and a Northern 101-A, with the only two differences I can find.     Pictures are labeled.
If it turned out that Western shipped Northern the coils, it wouldn't surprise me.

Jeff
Did Northern continue with the style later in 1937?  I am pretty sure that III-37 coils by Western were already the new type. Usually Northern lagged in product switches by some time if they made them themselves.
I also find it interesting that NE still used the same date format on these components as did WE. All the NE 101A coils that I have and have had of later date show a different format (M-D-YY).

unbeldi

Quote from: wds on August 25, 2015, 06:32:07 PM
Couple more pictures of the coil.  Could not find a patent date.  I tested the ringer - my ohm meter is not very acurate, the old needle style.  Registered about 6500 ohms.

That totally agrees with Jeff's measurement.  500 extra ohms is less than 10%, which was I think the tolerance, even if your meter is off a little, it wouldn't matter.

So these are probably high efficiency ringers for extra long lines?  I sure wonder what the impedance is at ringing frequency, must be huge.  10-12,000 ohms?

Ktownphoneco

I don't really know how long Northern continued making the coils in that physical configuration.        I do know that they dropped the letters "IND" from the label or stamp by the third quarter 1938, as the attached pictures will show, and the later coil design and assembly methods had been introduced.       
The Western date format was obviously still in use at that time as well.     Northern also used that format for their D1 / 202 sets, and 600 series subscriber sets as well.     I have a number of both the D1 / 202 and the 684 subsets on hand.     The next time I'm working on them, I'll try and remember to check to see when the date formats changed.

Question :   Ringing frequency impedance -   Is that the collective impedance of both coils in series while signal voltage is being applied at 20 Hz ?

Pictures attached. 

Jeff

unbeldi

#63
Quote from: Ktownphoneco on August 25, 2015, 08:59:28 PM

Question :   Ringing frequency impedance -   Is that the collective impedance of both coils in series while signal voltage is being applied at 20 Hz ?

Pictures attached. 

Jeff


Thanks for pics.

Impedance:  Yes.  It is across the ringer, both coils, and in my measurements I also include the ringing capacitor.  Of course this isn't pure impedance, because the ringer has a DC resistance also which is included in a simple voltage and current measurement.

Z (impedance) + R (resistance)  =  (AC RMS voltage)  /  ( AC RMS current)

If I didn't include the capacitor, the graph of  (Z+R) versus frequency would simply tend toward the DC resistance of the ringer, i.e. true impedance goes to zero as the frequency approaches zero.

unbeldi

Are you polishing those shiny screws in a vibration polisher?

Ktownphoneco

Thanks for that information.      The next time I read that phrase / terminology, I'll know what it's referring to.   

No, I polish them using a Dremel Advantage rotary tool.       I always polish the inside shoulders of terminal screws when I restore anything with electrical connections.    The buffing wheel usually "bounces" around the outer screw head leaving polish marks, so I end up polishing the entire thing, just so the finish is uniform.     I polish the old brass spade connectors on the conductors as well.
I have a "thing" about good electrical connections.

Jeff

unbeldi

Quote from: Ktownphoneco on August 25, 2015, 10:21:14 PM
Thanks for that information.      The next time I read that phrase / terminology, I'll know what it's referring to.   


I have a "thing" about good electrical connections.

Jeff

It keeps resistance down.  ;D

What I am measuring should be called effective impedances.
Impedance is really a complex quantity, meaning it has also a phase angle by which the current leads or lags the voltage cycles.  That requires an oscilloscope, perhaps I'll demonstrate that sometime on my induction coil measurements (101A). I believe I used a bunch of NECo 101A coils there.

Jack Ryan

Quote from: unbeldi on August 25, 2015, 09:45:25 PM
Of course this isn't pure impedance, because the ringer has a DC resistance also which is included in a simple voltage and current measurement.

Z (impedance) + R (resistance)  =  (AC RMS voltage)  /  ( AC RMS current)

What you are calling impedance, I would call reactance. Impedance is a complex value, Z = (resistance) + j(reactance) = V/I where both V and I are vectors.

Jack



unbeldi

Certainly correct, Jack.

At the minimum of the impedance vs. frequency graph, i.e. where the current is the largest as described, the capacitive reactance of the ringing capacitor cancels the inductive reactance of the ringer and the imaginary part of the impedance is zero, it's purely real.

unbeldi

So this Uniphone is certainly not just a nice phone, but also interesting technically. Just what I need to put on my to-find list.


unbeldi

Quote from: Ktownphoneco on August 25, 2015, 08:59:28 PM
I don't really know how long Northern continued making the coils in that physical configuration.        I do know that they dropped the letters "IND" from the label or stamp by the third quarter 1938, as the attached pictures will show, and the later coil design and assembly methods had been introduced.       
The Western date format was obviously still in use at that time as well.     Northern also used that format for their D1 / 202 sets, and 600 series subscriber sets as well.     I have a number of both the D1 / 202 and the 684 subsets on hand.     The next time I'm working on them, I'll try and remember to check to see when the date formats changed.

Question :   Ringing frequency impedance -   Is that the collective impedance of both coils in series while signal voltage is being applied at 20 Hz ?

Pictures attached. 

Jeff


I found what appears to be the new version of the 101A in the 1937 catalog.   The real surprise however is that the same picture appears in the first edition of that catalog in 1936. Hmmm.


Ktownphoneco

The lack of dates placed on a lot of Northern's catalogs, is always an issue.     My information on the N.E. T-6 first and second edition, is that both were printed in 1937.      They are the only 2 Northern catalogs that I'm aware of, that had a first and second edition.     I believe the reason for that lies on page 87 of the Northern T-6 First Edition.     I'm not sure how this was ever approved for printing, but as you can see, adding an "N" series handset to a patented Western Electric 211, does not make the telephone set a "Uniphone", type 3.     I would imagine, and this involves nothing more than common sense, that Western and Northern were most likely in the practice of exchanging newly minted catalogs.    I can only imagine the the corporate indignation on the part of Western, when they saw their patented 211 telephone set, re-named a Uniphone, with an "N" series dial attached.
I would imagine Chicago made a very quick and upset call to Montreal once they saw the T-6 First Edition catalog.      There are only minor changes of no particular significance between the two catalogs, which is probably why the information and picture of the 101-A induction coil is the same in both books.     If I had to hazard a guess, I'd say the two catalogs were printed not too far apart.     I purchased the N.E. T-6 First Edition off eBay, and it wasn't labeled "First Edition".    I always wondered why their was a "Second Edition".    Once I looked through the first one,  pretty much figured out why there was a second.     I wouldn't be surprised if I have the only copy of the first T-6 catalog printed.

Jeff

unbeldi

#72
Quote from: Ktownphoneco on August 26, 2015, 06:23:05 PM
The lack of dates placed on a lot of Northern's catalogs, is always an issue.     My information on the N.E. T-6 first and second edition, is that both were printed in 1937.      They are the only 2 Northern catalogs that I'm aware of, that had a first and second edition.     I believe the reason for that lies on page 87 of the Northern T-6 First Edition.     I'm not sure how this was ever approved for printing, but as you can see, adding an "N" series handset to a patented Western Electric 211, does not make the telephone set a "Uniphone", type 3.     I would imagine, and this involves nothing more than common sense, that Western and Northern were most likely in the practice of exchanging newly minted catalogs.    I can only imagine the the corporate indignation on the part of Western, when they saw their patented 211 telephone set, re-named a Uniphone, with an "N" series dial attached.
I would imagine Chicago made a very quick and upset call to Montreal once they saw the T-6 First Edition catalog.      There are only minor changes of no particular significance between the two catalogs, which is probably why the information and picture of the 101-A induction coil is the same in both books.     If I had to hazard a guess, I'd say the two catalogs were printed not too far apart.     I purchased the N.E. T-6 First Edition off eBay, and it wasn't labeled "First Edition".    I always wondered why their was a "Second Edition".    Once I looked through the first one,  pretty much figured out why there was a second.     I wouldn't be surprised if I have the only copy of the first T-6 catalog printed.

Jeff

Ah, thank you.  I have wondered about those pictures of the 211 set myself, I clearly remember, and was puzzled that it would be called a Uniphone.

That clears up a lot, and with the combination of the 101A being the same, confirms your dating. I would say these were printed in the second half, or even the last quarter of 1937.

Not sure where I got the year of 1936 from, for the first edition,  was that my handiwork on my PDF?

wds

#73
Well, I liked the 1937 phone so much I decided to keep it and just switch the shells.  The shells seemed to be identical, same patent dates, etc.  Now I have a good phone with all matching dates except for the receiver element.  I really like the looks of this with the chrome dial much better than the black fingerwheel on the northern dial.  One of the feet was crooked, so I took it off to have a look and noticed that the two nubs on the bottom had been filed off.  So I took a foot off of the other phone and found that the nubs do not fit this base.  The foot hole pattern on the 37 phone is different than the newer phone. 
Dave

unbeldi

Quote from: wds on August 26, 2015, 06:48:54 PM
Well, I liked the 1937 phone so much I decided to keep it and just switch the shells.  The shells seemed to be identical, same patent dates, etc.  Now I have a good phone with all matching dates except for the receiver element.  I really like the looks of this with the chrome dial much better than the black fingerwheel on the northern dial.  One of the feet was crooked, so I took it off to have a look and noticed that the two nubs on the bottom had been filed off.  So I took a foot off of the other phone and found that the nubs do not fit this base.  The foot hole pattern on the 37 phone is different than the newer phone.

Oh, I think I would keep it too.  But if you change your mind... well you know whom to bless.