Using a 315H subset with a 202 deskset

[RCMcDonald]

Hi All -

I'm looking to use a 315H subset I recently purchased as a subset with my 202 deskset.  Now, my 202 has a dial and the 315 came with the magneto removed.  I know that the 315H is not designed for use with a dial phone, hut It seems like I ought to be able to use the ringer and the coil, possibly with a capacitor added to make this work.  In looking at the wiring diagram I found at the link below, I see that this subset is supposed to be used with a local battery, which connects to the coil and through the hook switch to the transmitter element.  My question is how do I account for removing the battery in order to make this thing work with a modern system.  Or should I just drop in a network from a more modern phone and be done with it?

Link to the wiring diagram:
http://www.telephonecollectors.info/index.php?option=com_docman&task=doc_download&gid=2163&Itemid=11

Picture is below, too.

Thanks for the help.

Bob McDonald

[Phonesrfun]

Bob:

I would advise against modifying the 315 to a common battery configuration. 

You would need to replace the incuction coil; you would need to have a ringer and talk capacitor such as the combined 195A found in a 302; and the unbiased low resistance ringer is just not right for a common battery line.  In other words, all you have that are really usable for a 202 is the empty box.

Besides, the 315 without modification might be of value to someone collecting local battery phones, and generally speaking, modifications to good antique equipment is not encouraged.

[wds]

We just had this discussion not too long ago - look at this link:

http://www.classicrotaryphones.com/forum/index.php?topic=5533.0

The coil that is in the 315 box probably won't work as it's more than likely a local battery coil.  Hopefully you can get some ideas from this other link.

[RCMcDonald]

Good suggestions.   Thanks gentlemen.  I have an old 302 I can pull the coil and condenser from.  I'll see if I can get it to work without harming the box too much.

[dsk]

I would have put in "new" components, whatever I had. The parts could be glued or taped to prevent drilling in the box.  

Since the 202 is a sidetone set, you may use the exsisting coil and a capacitor make the circuit.

A capacitor of 1 microfarad would be fine. (rated at least 150V)

The diagram in this post will be fine, just replace the resistor with the highest ohm coil from the old coil, and leave the low ohm coil unused.  http://www.classicrotaryphones.com/forum/index.php?topic=5664.msg68667#msg68667


dsk

[Phonesrfun]

The 202 is an antisidetone set.  Using the diagram suggested would be using it in a sidetone configuration.  I would use the 302 components.

[dsk]

  oops.
Then I agree. Makes it a little bit more complicated, but definitely better.

dsk

[Greg G.]

Good suggestions.   Thanks gentlemen.  I have an old 302 I can pull the coil and condenser from.  I'll see if I can get it to work without harming the box too much.

Why not just use the 302 base as a subset?  You can either get a cover from Ray Kotke, or if you really want to use the box, I think the entire 302 base will fit inside it.