Hello here is a Clear Channel Corporation SP-1 Speech Processor module, intended for the AR-3500 radio, this can and will work in many radios, just takes the right technician to install it, these make your audio scream especially on single sideband

This is not a linear amplifier 

Original receipt from RF Parts and installation instructions and schematic included 

I ship super fast, same day as payment posts, your item will be mega packed and shipped out within minutes, you will receive a valid tracking number within minutes....... I only use USPS Priority Mail for the fastest delivery time on Ebay, typically 2-3 days coast to coast 

I have been here on Ebay since January of 1998, deal with a Trusted Seller you`ll be Happy you did