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534AT ringer

Started by wds, May 20, 2013, 07:50:52 PM

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wds

Grabbed this 534AT ringer.  It's in great shape, and had this tube, I'm guessing for party line ringing.  Once I disconnected the tube, the subset worked just great.  Is there any way to tell what frequency the tube is set for, or is it used for something else?
Dave

paul-f

#1
A general description of how ringing works with a cold cathode tube is found in this BSP:

  C31.122

[Link revised]
Visit: paul-f.com         WE  500  Design_Line

.

Phonesrfun

Tubes were ways of passing normal 20 cycle ringing current to a straight-line ringer.  The combination of ringing tip to ground or ring to ground, or bridged, combined with bias voltages on the tube is what created the ability to selectively ring several parties.

They were not set to specific frequencies.
-Bill G

wds

Ok.  Is there any way to make the tube function and cause the ringer to ring?
Dave

poplar1

#4
Try this to use on non-party line:

Line cord: Red (-) to L1, Green (+) to Y/L2

Ringer: Red to L1, Black to K

Tube: Yellow to L2, Red to K, Black to K


See Kenny's diagram for a rewired 306


http://www.classicrotaryphones.com/forum/index.php?topic=5374.0

This may not work if you have a VOIP "line."


"C'est pas une restauration, c'est une rénovation."--François Martin.

paul-f

If you prefer the BSP view, the wiring is according to Figure 3 in C31.122 issue 4 -- but with the wires going to GND moved to L1 to match modern two-wire ringing.
Visit: paul-f.com         WE  500  Design_Line

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Phonesrfun

#6
Just as a note, don't assume that your house is wired correctly.  Just because the red wire is supposed to be negative, you should check it out with a volt meter.  The important feature in David's (Poplar's) instructions are the negative and positive voltages on the wires, rather than the color of the wire jackets.  The color just designates what is or was at one time, the norm.  Also, as he said, if you have a VoIP system, rather than POTS, it might not work for you.  that's because a normal POTS line uses 48 volts, which the tube needs in order to be biased enough to operate.  Most VoIP ATA's operate on 24 volts.  When I tired a tube on my VoIP based system, I got almost no results.  It worked fine on a POTS line, but not on the modern VoIP line.
-Bill G

wds

#7
I've tried all the wiring variations, and no luck.  I have 50 volts a/c ringing voltage, so I wonder if that is still not enough.  The BSP seems to indicate that the tube needs 60 - 75 volts?  This tube is a 333A, and all the documents refer to 425 or 426 tubes.  Couldn't find any information about the 333a tube, so maybe it requires even more voltage?  

The wiring diagram on the box is painted over - since the ringer uses the tube to ring, I assume the condensor is for the receiver?  If so, doesn't that mean the subset is anit-sidetone even thought the 534 is a sidetone subset?
Dave

rdelius

The tube has to get high enough voltage to "fire".It has to be higher than the line voltage or there would be false ringing if they were close in voltage. You might see an orange or purple glow through chips in the paint  when the tube fires when ringing

wds

I did find the reference to the 333A tube with the 534AT subset.  It seems to require much more voltage than I'm getting out of my phone line.  I wonder, has anyone actually been able to get one of those tubes to work on their phone line?   
Dave