Thread: "Butt" 'phone
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Old 14th May 2019, 3:43 pm   #1
Dave Moll
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Join Date: Feb 2005
Location: West Cumbria (CA13), UK
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Default "Butt" 'phone

At the NVCF on Sunday I acquired the "butt" 'phone pictured below - which I have had a bit of fun getting working. The main reason for posting is that I don't recognise the model and there doesn't seem to be anything resembling it on Bob Freshwater's site. Does it have a separate model number or is it just a variation on the 280?

Returning to the "fun", I started by noting that the dial was either sticking or returning very unevenly. It turned out that the original dial had been snipped out leaving loose ends flapping about inside, and they were fouling the dial contacts of the disconnected dial. Once removed from its enclosure the dial was working OK.

Next stage was working out how to dismantle the case of the 'phone, which was clearly in two parts. In the end it transpired that the two screws in the metal bar below the dial and two nuts either side of the transmitter inset were holding it together between them. Once they were removed, the back lifted off so that I could now get at the innards, including the wires to extend them for re-attachment to the dial.

Before doing this, I decided to test the rest of the function (having found replacements for the two missing screws to the receiver), and was a little puzzled to discover that it was making a loop (evidenced by a faint dial tone being audible) without the press button being pressed. Doing so merely made the sound louder by making a "proper" loop. This problem was caused by the capacitor in series with the receiver leaking like a sieve. Replacing this restored normal operation, so I could return my attention to the dial.

The orange dial wire simply went back to the press switch, so I decided to replace this, but with the pink and brown wires it was easier just to solder on extra lengths of wire. Having re-assembled the 'phone, I then reconnected the dial to the extended wires to achieve a working unit.
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