Monday, November 16, 2009

TELEPHONY, CONTINUED

Disassembled, cleaned, painted (lacquer!) and have begun, slowly, to reassemble the hotel phone. First, a collection of chassis parts -- the things in the center are the back of the transmitter (microphone) and the receiver (earpiece) hook: Basic assembly -- the front of the case is hinged to the back and I have test-fit the network, bell and hookswitch (less hook; it goes in later). Shown with a few of the tools used, including pen-type oiler at far left, used to put one drop of light oil on the hookswitch pivot (funny shading is the lighting, mild orange-peel texture is deliberate):No dial, receiver or transmitter yet. The latter is a whole collection of small parts, most of which I still have to clean and polish. Dial, hookswitch and receiver will be the very last parts fitted.

I did manage to remove and photocopy the schematic. Here's a black & white scan: Click for larger -- I have it larger still and in color for more detail, if anyone else is working on a Kellogg 1155-A or 1157-A telephone.

9 comments:

  1. Should have asked this with the last post: Will an old analog phone work with a modern system without replacing major parts?

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  2. VERY cool!

    Will the completed phone actually, you know, phone?

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  3. Here in the States (other counties may have different standards -- readers, please check) until the last decade or so, the answer was an unqualified YES!

    Now, it's a qualified "Yes:" You can still receive calls on a classic telephone (even a wooden, local-battery type!) but you might not be able to dial out. The basic phone system as you encounter it at the customer side of the wiring is still a two-wire, analog system. Even if you're using a VOIP provider, the interface is essentially the same standard as it was a century ago.

    However, a century ago, direct-dialing was uncommon, though hardly unknown; the first automatic telephone exchange was installed in LaPorte, Indiana in 1892, 20 years before Bell decided it was a good idea. The pulse-counting automatic exchange is an add-on to the POTS (Plain Old Telephone System) standard.

    Touch-tone (dual-tone multi-frequency) dialing is another add-on and new telephone switches (and VOIP boxes) may be able to read only DTMF tones, not dial pulses. (Some modern phones have Pulse/Tone switches, for the few exchanges that can't read DTMF).

    But not to worry -- you can buy a pulse-to-DTMF converter! Here's a plug & play version I just found online and here's a tiny one to wire in a phone.

    As of now, that's the major interfacing issue -- and in many areas, even that is not an issue.

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  4. Nice stuff they have. I like the Model 32A Deskset, and the Model 44 Dial Candlestick is also appealing. It would be fun to use a Candlestick on Skype!

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  5. Pulse to DTMF converter? I think Mrs. Drang's antique whatsis phone (The boat anchor of phones...) may come out of storage!

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  6. Nicely done. And I like your taste in tools; the screwdrivers are the type of classic models I grew up with.

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  7. My 70 year old Western Electric 302s and 50 year old 500 sets dial out just fine on my Bellsouth/ATT POTS line.

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  8. No civilization that relies on disposable technology will survive for long.

    WV = wayste

    LOL

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  9. We've got an antique phone from 1895 that actually works. Somebody prior to our ownership spliced a modular plug onto the end of the original cable and it works like a charm. I'll try to get some photos, as I'm sure RX will appreciate it.

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