Hi,

I have a question on the 501A. I would like to change the phone co ringing to intercom buzzers and ringers for intercom, to switch things up.

According to the ITT practice on page 5, to use buzzers for CO and ringers for intercom. Connect 18V ac to C48 and ring battery to C50.

Here is the link to the manul
http://www.telephonecollectors.info/strombergcarlson/kellogg/PDF/1979_K501A_KSU_PRACTICE.pdf

On block C I see two wires on each row on C48 and C50, would I need to move both? See photo.

Block C
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