ITT 500 clapper not hitting gongs

[etamme]

Hi All, long time no see. 

A friend of mine bought a model 500 which is ITT branded, and uses the modular terminal network.  Originally it was not ringing, so I rewired it and now the clapper arm vibrates when a call comes it, but not with sufficient amplitude to actually hit the gongs.  I tried removing the weight from the end of the clapper arm, but still it does not swing enough to hit either gong. 

It's wired as shown in http://www.classicrotaryphones.com/forum/index.php?action=dlattach;topic=2767.0;attach=66679;image

However, the hook switch unit has several other wires which i just didnt touch: gray/black, gray/green, gray/yellow, gray/brown, gray/white, gray/red - it's not clear to me what these wires do, the seem to be connected to the brass plate/pins that make up the hook switch it self.

Here are photos of the phone: https://imgur.com/a/jC3jRpR

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Moderator Edit:  images downloaded from imgur, rotated and added to this post for forum posterity

[poplar1]

The brass weight is missing in the photos. In any case, even with the weight, depending on the frequency stamped on the ringer, it may or may not work on today's lines. This is a "frequency selective" ringer for party lines, and as such is designed to respond to only one frequency.

[etamme]

Thanks for the quick reply.

I removed the brass weight to see if it would allow the clapper to get enough amplitude to strike. 

I have this phone hooked to a VoIP adapter, it may be possible to specify the frequncy within the adapter.  Do you have any more info about what frequency the ringer responds to?  I tried to find information on the "qBA" ringer but havent found much.

[HarrySmith]

It may be one of the numbers stamped on the bottom. If your adapter can be adjusted try the different numbers and see which responds best, IIRC I saw 60, 20 & 44 stamped there. Maybe one of those is the frequency?

[poplar1]

Show the brass weight and perhaps someone can identify. The larger the weight, the lower the frequency.