[Towertalk] Relay Summary

[Jerry Kincade]

Ma Bell used that principle with what was called "sealing current" to help
keep their gazillion relays working for many, many years. Now, of course,
it's all digital switches in the central office, but back then whole crews
of people were dedicated to relay maintenance, which was very labor
intensive and costly. The noise level from all those thousands of relays
stepping and clicking in a central office as calls were dialed and routed
through was amazing. Now it's just a low "hmmmmmmmm" from blower motors. :-)
The "wiping action contacts" idea certainly makes sense.
73, Jerry W5KP

----- Original Message -----
From: "dan hearn" <dhearn@ix.netcom.com>

> In fact there was no material that would guarantee total small signal
> reliability.They talked about bleeding a small current thru the contact
> via a large resistor or RFC to help punch thru the contaminent film.