I just took delivery of some phones from NH Telephone museum .
One is marked on bottom as 307 A/C
I connected it to a line to hear only faint sounds. I then cracked open the case to find an odd component that I never have seen before . It is just in front of the bell and marked "RET 266A" and "2V47" or possibly the date of "2/47" I have no idea what this component is but looks like a coil.
Does anyone here kow what this is?
Can this phone be re-wired to work normally?
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EDIT
307 is apparently a unit wired for local battery
It would be a local battery telephone - probably for long line service.
Jack
Quote from: markosjal on November 18, 2020, 08:33:00 PM
Can this phone be re-wired to work normally?
It has the wrong IC for CB operation but if you add a battery it should work properly.
Jack
IC??? Integrated circuit? Probably means Inductor?
Quote from: markosjal on November 18, 2020, 10:38:25 PM
IC??? Integrated circuit? Probably means Inductor?
Induction coil.
Jack
So it seems my options are to replace the Coil (and capacitor too) , which the coil an be purchased here
https://www.ericofon.com/catalog/parts/networks.htm
Or
figure out how to wire it for local battery and see if a dial can be added on local battery phone
I think there may be an issue connecting a dial to a local battery phone , so the second option may be the better one.
Search the forum for "307" and you'll find several good past discussions.
Also, the BSPs help. Some BSP numbers to check can be found here:
http://www.paul-f.com/we300typ.htm#307 (http://www.paul-f.com/we300typ.htm#307)
"307A/C" indicates that it can be either manual (A) or dial (C). This is not a "local battery telephone" -- rather, it is Common Battery Signaling, Local Battery Talk. The battery is needed because of the long loop.
I have several of these along with the matching 357 wall sets. they can be converted to common battery. some rewiring is required. no parts need to be removed. refer to the BSP wor wiring diagrams and take note of the jumper located under on of the screws on the induction coil... that ties the coils together. if you want to more details, just ask.
Quote from: poplar1 on November 19, 2020, 05:34:56 PM
"307A/C" indicates that it can be either manual (A) or dial (C). This is not a "local battery telephone" -- rather, it is Common Battery Signaling, Local Battery Talk. The battery is needed because of the long loop.
Well, that
is a local battery telephone but it is why I suggested connecting a battery and then it will work. There is no picture so I don't know if the phone has a dial or not.
Long line telephones were very often LBT-CBS.
I should add that there are zillions of 302s and not many 307s. I would not change it.
Jack
enclosed is a copy of the schematic and conversion instructions, try it and see if you like it that way, I've done this to all of my 307's and 357's. that way, thay are usable on todays phone lines.
Thanks, I found that diagram in its origial form and made the following from it!
so, there was conversion instructions already out.... I didn't even know they had this practice. I'll have to reference it for future use!