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Old 2nd Mar 2021, 12:14 am   #21
IOWPhoneGuy
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Join Date: Feb 2021
Location: Newport, Isle of Wight, UK
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Default Re: Problem with telephone 248 and bellset 44.

On rebuilt phones, the symptoms you decribe are commonly caused by the pink and orange wires to the dial being swapped over. These colours tend to fade, especially on cloth covered wires and are easily confused when putting a phone back together after cleaning.restoration. You will also get the same symptoms when a dial is fitted to a CB phone, i.e. with no dial fitted, if the CB link (between T3 and T4 on 248 and other 200-series phones) is not removed.

What I describe above is a phone/dial problem, not a bellset 44 problem. As far as I can tell from the diagrams, there is no easy way to produce the same symptoms by messing with the bellset 44 (or 39 for that matter).

I have two (soon to be one hopefully) working 248/44s and one 248/39 so have some recent practical experience in this area. I have them wired as original, i.e. a two-wire connection using the bell capacitor in the bellset and an external bell, generally a 64D but any simple bell, e.g. bell 1A, will work. Fit a REN reduction resistor in the bell.

You can also bypass the bellset 44 altogether, wiring the 248 as a 232 as all a 248 is is a 232 with extra cradle swithc contacts. With a modern-line cord three wire connection a simple bell, including REN resistor if needed, is all you need. I have had to do this as the one of my 248/44s came without the phone-to-bellset cord, which is nigh-on impossible to find.
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Old 2nd Mar 2021, 7:40 pm   #22
john777
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Default Re: Problem with telephone 248 and bellset 44.

Hello
Thanks for all your help so far
I have disconnected the bellset from the top unit completely and wired as above, but there is no dial tone
Any ideas why this could be.
I have two working 232's so am going to try and compare the wiring tomorrow, but any other suggestions greatly received
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Old 2nd Mar 2021, 10:07 pm   #23
Dave Moll
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Default Re: Problem with telephone 248 and bellset 44.

Do you get dial tone if you turn the dial? If so, it may be that the dial is wired back-to-front so that the pulsing contacts and dial-off-normal contacts are transposed.

Failing this, do you get dial tone if you move the red wire of the line cord from T3 to T4, thus bypassing the dial? Clearly you won't be able to dial with this wiring.

If neither of these restores dial tone, I can't see why eliminating the bellset (which may have been shorting the dial via T9) has stopped you getting dial tone.
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Old 3rd Mar 2021, 7:19 pm   #24
john777
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Default Re: Problem with telephone 248 and bellset 44.

hello
Have wired the jack plug straight into the phone as per the last post, but there is no dial tone.
I then swapped the red and blue and was able to get a dial tone but not dial out
Any advice on how to proceed greatly appreciated
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Old 3rd Mar 2021, 9:30 pm   #25
Dave Moll
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Default Re: Problem with telephone 248 and bellset 44.

Quote:
Originally Posted by john777 View Post
Any advice on how to proceed greatly appreciated
Have you tried what I suggested in post 23?

By connecting the red wire (B leg of line) to T2, you are connecting the receiver directly (via a couple of coils and a resistor) across the line, so you will indeed hear the dial tone that is present. You are also applying the DC line voltage across the receiver, which is not a good idea as it can cause permanent magnetisation of it if continued for any length of time.
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