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Old 26th Sep 2021, 9:12 pm   #1
marrold
Diode
 
Join Date: Aug 2021
Location: Watford, Hertfordshire, UK.
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Default GEC 746 with high impedance ringer.

Hi all,

I picked up a cheap 746 at RetroTech today and took the shell off to reveal it's not a "standard" 746, as it has 2x 1.25K coils on the ring with a capacitor inbetween, and two seemingly random 3.3K resistors attached to spare terminals. It also has an additional hook switch.

Does anyone know the story with this one?
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Last edited by marrold; 26th Sep 2021 at 9:19 pm.
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Old 30th Sep 2021, 11:35 am   #2
dagskarlsen
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Default Re: GEC 746 with high impedance ringer.

The extra hook sw. and the high impedance ringer may be needed to be approved in some countries that had their own rules, I see absolutely no reason for those 3k3 resistors. Maybe it was relevant for some shared line systems to indicate who that should be billed for what?
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Old 30th Sep 2021, 10:35 pm   #3
winston_1
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Default Re: GEC 746 with high impedance ringer.

Quote:
Originally Posted by dagskarlsen View Post
I see absolutely no reason for those 3k3 resistors. Maybe it was relevant for some shared line systems to indicate who that should be billed for what?
They are shown in the circuit on the paster.
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