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CEI and WJ Signal Monitors


CEI and WJ signal monitor guide

SM-9301 (?)

Here's a bit of history. This appears to be CEI's first signal monitor (SM). It has no model number and bears the very early logo on the front.


This is a slightly later CEI signal monitor, the SM-8512. It was designed for surveillance use with the R-390 and R-390A series of receivers.


One the other end of the time line is the WJ-9205 Signal Monitor. This unit will display three traces, each from a different receiver with different sweep widths.