Wurlitzer 2300S selector mechanism

Hi, I'm currently looking at the schematics for the selector mechanism on a Wurlitzer 2300S, and could really use a bit more information on the mechanical operation of the mechanism. I can follow most of the system through the circuit diagram, but I'm confused as to the operation of the latch switches. Are these switches made whenever the latch solenoid is powered, when the latch solenoid is on and any letter/number combination is pressed, or when any letter/number combination is pressed regardless of whether or not the latch solenoid is powered?

EDIT: Would also appreciate any information on the series switches. As I understand it, these are broken when either a letter or number is fully depressed and latched in place.

Kind regards

Matt

Matt, latch switches are designated :Letter and Number. When the latch solenoid is pressing a letter and/or number causes the associated pawl to slip off it's catch and actuate the switch associated with it. From what I recall, this action is only possible if the solenoid is energized.

The solenoid also actuates another set of contacts. These open the direct connection to the low-AC line and leave the coil connected through a 5 watt resistor. Another set on this same gang connects the "Select" light -also through a 5 watt resistor.

The easiest way to understand this area is to manually pull-in the solenoid and observe the action of the switches as you simultaneously press a button. As a general rule, contacts in a multi-throw arrangement should brake one connection before it makes the alternate one.

In this assembly the main problems are:

1) Poor contact due to weak leaf blades. Wurlitzer should have used stronger blades here as this was a problem even after a few years of service.

2) The pawls that mechanically couple the action of the keys to the leaf switches can develop gummy bearings especially after a long period of non-use. Checking for this is easy -fixing it can be a pain...


BTW: You might also check this group for more info: https://groups.yahoo.com/neo/groups/wurlitzer/info

Rob-NYC

Thanks Rob, that's exactly what I was looking for.

Many thanks.

Matt