I am looking to purchase a "Vintage" Electrosonics International (Riverside New Jersey) Instalert Model ET-10, Ten Position Tone Encoder. The model is grey in color and was used by many fire departments in the Northeast US for encoding their fire department and ambulance tones.
I am also looking for other vintage tone encoders of other manufacturers.
Also, I am looking for someone with a great deal of expertise in this area to assist with a few questions about tone formats and encoders, i.e. Bramco, GE, Ledex, Plectron, Reach, Zetron.
I can be reached at firstname.lastname@example.org