Realistic 21-404 TRC-504 Two-Way Audionic Transceivers - Tested & Working

This is the Realistic Voice-Operated Two-Way Audionic Communication System, catalog No. 21-404, a pair of vintage 49 MHz FM voice-actuated transceivers complete with earpieces, manual, and original box. A great pickup for collectors and vintage electronics enthusiasts alike.

Features & Specifications

• Two Realistic voice-actuated FM transceivers (model TRC-504 / Cat. No. 21-404) with VOX and VOL slider controls and orange antenna toggle switch
• Voice-operated (VOX) hands-free transmit and receive with 49 MHz FM operation, falling within the VHF band
• Rated range of up to 1/4 mile line of sight between units
• Two coiled-cord earpieces plus two clamshell cases holding multiple interchangeable earpiece tips for a customized fit
• Includes original printed TRC-504 instruction manual and original printed cardboard box (Cat. No. 21-404)
• Each transceiver runs on one 9V battery (two 9V batteries total required); batteries are not included
• Black plastic housings with orange accent switch, classic 1970s RadioShack/Realistic design

Condition Description

• Transceivers are in excellent, mint-condition cosmetic shape and fully tested, working as they should.
• The included box shows heavy wear including water staining, torn edges, and general surface wear, though this does not affect the units themselves.
• Set is complete with both transceivers, both coiled-cord earpieces, two clamshell cases of interchangeable earpiece tips, and the original TRC-504 manual.
• Batteries are not included; each unit requires one 9V battery to operate.

Shipping & Returns

• Ships next business day.
• Packed safely and securely.
• 30-Day Return Policy (buyer pays return shipping).
• Shipping calculated by eBay at checkout.

Why You'll Love It

There is something special about holding a piece of 1970s RadioShack ingenuity that still works exactly as intended decades later. This Realistic Two-Way Audionic Communication System lets you experience genuine voice-activated FM communication the way it was originally designed, no push-to-talk fumbling, just speak and it transmits. Complete sets like this one, with both transceivers, the full earpiece assortment, manual, and original box, are increasingly hard to find intact, making this a rewarding addition for vintage electronics collectors, retro tech enthusiasts, or anyone who appreciates analog engineering from a simpler era. The worn box only adds to its story, while the transceivers themselves remain in excellent tested condition and ready to use.