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Ringer help needed on a Stromberg Carlson 3-C 500D

Started by lou2ser, February 20, 2011, 10:49:35 PM

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lou2ser

I am troubleshooting a Stromberg Carlson 3-C 500D.  Everything works
except the ringer.  I've verified the wiring with this schematic
(http://www.porticus.org/bell/images/500c_d_schematic.gif)
( dead link 05-02-21 )

and everything looks good to me.  Here are some photos of how it's wired.











Here are links to high resolution versions of the above photos
http://i.imgur.com/zlKLt.jpg
http://i.imgur.com/Vyl66.jpg
http://i.imgur.com/KLIm2.jpg
http://i.imgur.com/HvPNp.jpg
http://i.imgur.com/cBHFm.jpg

I've also tinkered with the spring next to the clanger.

Can anyone see anything that my newbie eyes missed? 

The only other
possibility is that VOIP Analog Telephone Adapter I'm using isn't
drawing enough power to drive the bell, but from what I've read mine
is one that works with rotary phones.  I'm using a Grandstream
HandyTone 502.  I don't expect this forum to have the expertise to assist me with this issue, I'd just like to know everything on the phone looks good before I start looking down other rabbit holes.

Thanks!

Adam

It looks all correct.

This is probably not the problem, but I would remove the black wire from the line cord and tape and store it, or connect it where the yellow wire from the line cord currently is.

When you say you fiddled with the spring, did you move it from one position to the other?

Does it not ring even a tiny bit?  If not, your ringer may be bad.  I exclusively use HT-502s in my system here, they ring all my phones just fine.

Can you connect another different phone to the ATA and ring it, to rule out that the ATA is defective?
Adam Forrest
Los Angeles Telephone - A proud part of the global C*Net System
C*Net 1-383-4820

lou2ser

The black wire was originally disconnected and taped off.  This photo was taken in the middle of some fiddling, it's also been attached to G.  It's since been taped off again.

No ringing whatsoever.  No movement at all.

Yes, the spring was moved from the left to the right and back again.

I don't have another ATA to test with, but I'm trying to locate another phone to test my current ATA.  Who would have guessed a whole group of friends in the mid 20s to mid 30s wouldn't have a single landline phone in storage.  :)

Thanks so much for confirming the wiring.  I'll test with another phone and if that works I now know that I got a bad ringer.


Adam

Another very unlikely possibility:  The Slate and Slate/Red wires from the ringer correctly connect to A and K on the network in your picture, but the unlikely possibility is the capacitor inside the network between terminals A and K is open (bad).  That would prevent the ringer from working.

I say it's unlikely because I've never had the A/K capacitor in a network go bad, ever.
Adam Forrest
Los Angeles Telephone - A proud part of the global C*Net System
C*Net 1-383-4820

lou2ser

Would it be possible to test the ringer by shorting two of the wires with a 9 volt battery?

Adam

Ringing is high voltage, like 90V, AC.  To test a ringer externally, you'd have to connect the ringer to a different ringing voltage supply, like one used in a key system, for example.

If you connect a ringer to a 9V battery, you'll just make the battery mad.  :-)
Adam Forrest
Los Angeles Telephone - A proud part of the global C*Net System
C*Net 1-383-4820

lou2ser

Quote from: masstel on February 21, 2011, 12:00:27 AM
Ringing is high voltage, like 90V, AC.  To test a ringer externally, you'd have to connect the ringer to a different ringing voltage supply, like one used in a key system, for example.

If you connect a ringer to a 9V battery, you'll just make the battery mad.  :-)

That explains the shock I gave myself as a teenager when I was last playing around with rotary phones.  Don't ask how or why, but I was testing to see how much electricity the phone lines used by touching the wire to my tongue when a call came in.  Ouch!

Dennis Markham

I know you said you tinkered with the bias spring.  I agree with Dave (masstel) that the wiring looks right.  I'd also remove that black line cord even though I doubt it has a bearing on the ringer.  Look at this link:

http://www.classicrotaryphones.com/forum/index.php?topic=2905.0

Reply #2...I posted a photo of the bias spring position that usually is the best position.  Make sure yours is like the one in the second photo.  

Adam

Quote from: lou2ser on February 21, 2011, 12:03:03 AM
That explains the shock I gave myself as a teenager when I was last playing around with rotary phones.  Don't ask how or why, but I was testing to see how much electricity the phone lines used by touching the wire to my tongue when a call came in.  Ouch!

That reminds me of the funniest thing I've ever seen on eBay.  It was in the description for a hand-crank magneto ringing generator like they used to use in the old wooden wall phones.

The description said (paraphrasing), "I know it works because I had my brother hold the ends of the wires while I cranked it."

:-)
Adam Forrest
Los Angeles Telephone - A proud part of the global C*Net System
C*Net 1-383-4820

AE_Collector

Working for the Telco I've been nailed by 90VAC too many times to remember. Maybe I would be able to remeber if I HADN'T been nailed so often. I have had one small little gray patch of hair around the back of my neck for years and years that I put sown to getting nailed one of those times. It is slowly disappearing now though as everywhere else is catching up.

Terry

Phonesrfun

#10
I think I would first test the ATA with another analog phone with a legacy ringer like another model 500 phone just to make sure the ATA is working and further isolate the problem to being just the telephone itself.  Assuming the ATA can ring another known good phone, you will know for sure that the problem is in the phone in question and not the ATA.  Your ATA, if working should have absolutely no trouble ringing your phone.

Assuming the ATA is good it's time to isolate the problem within the phone.  The ringer circuit is very simple; there are only two elements besides the wires that make up the ringer circuit;  The ringer coils and the ringer capacitor.   They are wired in series, and as that series set, are bridged across L1 and L2, which is the incoming line.

As was mentioned by Dave (Masstel), the capacitor, a .5 mF 250 volt capacitor, is contained inside the network can and is connected to terminal points A and K.

The ringer coil has two windings and the capacitor is wired between the two windings in series.  

The first ringer coil winding is a 1000 ohm winding and is hooked to the black and slate wires.  If you have access to an ohm meter, you can disconnect the black and slate wires from the phone and check for resistance/ continuity.  If there is no resistance, that coil section is bad.  Do the same for the red and slate/red wires, but make sure to disconnect them first  That coil is 2650 ohms, and if it is open, it is bad.  Disconnecting the wires from the phone insures you are measuring just the ringer coils and not the rest of the phone to which they are connected.

Actual DC resistance will usually not be exactly what the coils are made out to be, so the most important thing is that there be a ballpark resistance as measured across the two sets of coil wires.

If the ringer coils check out, the problem may be the capacitor.  If you have a digital multi-meter with a capacitance checking function, this is an easy thing to check by disconnecting the ringer wires from A and K and using the meter probes on A and K to check for the capacitance value.  If you cannot get an intelligible reading, then the capacitor is bad, and needs to be replaced with an external capacitor that you can buy at Radio Shack.

Like Dave said in an earlier post, I also don't think I have ever seen a capacitor go bad, but I have seen ringer coils go bad.

If you determine the ringer to be bad, you can find one easily enough.  They are very readily available, and while they do fail, they don't fail very often, so you should not fear getting a used one.  Besides, there just aren't a lot of NOS ringers out there.

I would personally not try to repair a bad ringer coil.  You would wind up being there for a week with yards and yards of fine wire all over the place unless you have a coil winder, which not everyone has.
-Bill G

lou2ser

I'm overwhelmed with the level of response.  Thanks everyone!

This morning I attempted connecting the phone to the other port on the ATA.  No change.

A co-worker is bringing a landline phone for me to test with tomorrow, I'll report back then.  It's not a rotary phone but it's the best option I have right now. 


Adam

Quote from: lou2ser on February 21, 2011, 09:51:19 AM
A co-worker is bringing a landline phone for me to test with tomorrow, I'll report back then.  It's not a rotary phone but it's the best option I have right now. 

For the purposes of this test, which is seeing if your ATA can successfully ring a phone, whether the phone is touch-tone or rotary is completely irrelevant.  The ringer circuit is the same in both.
Adam Forrest
Los Angeles Telephone - A proud part of the global C*Net System
C*Net 1-383-4820

lou2ser

Quote from: masstel on February 21, 2011, 11:29:05 AM
Quote from: lou2ser on February 21, 2011, 09:51:19 AM
A co-worker is bringing a landline phone for me to test with tomorrow, I'll report back then.  It's not a rotary phone but it's the best option I have right now. 

For the purposes of this test, which is seeing if your ATA can successfully ring a phone, whether the phone is touch-tone or rotary is completely irrelevant.  The ringer circuit is the same in both.


My tests with a second phone reveal that there is nothing wrong with the ATA.  Because no one has ever seen the capacitor in the network block go back, I'm going to check the classifieds to see if I can find a ringer.

Thanks again everyone!  I'll let you know if the ringer fixes it.