Richardson Engages Ernst & Young LLP as Independent Auditor

LaFox, IL, Wednesday, September 14, 2005: Richardson Electronics, Ltd. (NASDAQ: RELL) today announced that its Audit Committee of the Board of Directors engaged Ernst & Young LLP (“E&Y) as its independent registered public accounting firm to audit the Company’s financial statements for the fiscal year ending June 3, 2006.

The change in auditors was not the result of any disagreement between the Company and its former auditors, KPMG LLP, on any matter of accounting principles or practices, financial statement disclosure, or auditing scope or procedure.

About Richardson Electronics
Richardson Electronics, Ltd. is a global provider of “engineered solutions,” serving the RF and wireless communications, industrial power conversion, security and display systems markets. The Company delivers engineered solutions for its customers’ needs through product manufacturing, systems integration, prototype design and manufacture, testing and logistics. Press announcements and other information about Richardson are available on the World Wide Web at http://www.rell.com/investor.asp.

For details contact:
Edward J. Richardson Chairman & CEO Phone: (630) 208-2340 Email: info@rell.com		Corporate Headquarters 40W267 Keslinger Road PO Box 393 LaFox, IL 60147-0393 USA Phone: (630) 208-2200 FAX: (630) 208-2550
For Immediate Release

2W-B Photoelectric Smoke Detector

System Sensor’s i3™ series smoke detectors represent a significant advancement in conventional detection. The i3 family is founded on three principles: Installation ease, Intelligence, and Instant inspection.

Features:

* Plug-in detector line – mounting base included
* Large wire entry port
* Removable detector cover and chamber for easy cleaning
* Built-in remote maintenance signaling
* Drift compensation and smoothing algorithms
* Simplified sensitivity measurement
* In-line terminals with SEMS screws
* Mounts to octagonal and single-gang backboxes, 4-square backboxes, or direct to ceiling
* Stop-Drop ’N Lock™ attachment to base

SD505-AIS Addressable Ionization Type Smoke Detector

The SD505-AIS ionization smoke detector has two chambers: a sampling chamber and a reference chamber. Smoke or invisible combustion gases can freely penetrate the sampling chamber, but the reference chamber is virtually closed to prevent easy entry. With both chambers ionized by a single radioactive source, a very small current flows. Presence of visible smoke or invisible gases greatly influences the current flow in the sampling chamber, changing the voltage ratio between the chambers. This difference is amplified inside the detector. After reaching the critical level, the detector triggers into alarm.

Features:

• Low profile, 2.25 inches, including base
• Simple and reliable addressing without mechanical switches
• Automatic compensation for sensor contamination
• Built-in fire test feature
• Simple detector sensitivity testing through the control panel or remotely through a Windows based computer. (5590 or 5595 software required for remote testing.)
• Adjustable sensitivity
• Vandal-resistant locking feature
• Field cleanable

ESL 521-BXT Smoke Detectors - GE Sensors

The ESL 500N series 2&4 wire conventional photoelectric smoke detectors bring together trusted technology and a full line of needed features to meet the demands of every type of application. The 500N offers sounders in 2&4 wire applications, specifically to meet residential code requirements. The 521NCSXT has the added benefit of low current draw which makes it compatible with a wide variety of control panels. The ESL 500N series also offers choices for optional auxiliary relays and isolated heat sensors, not available before in the ESL 500 series. ESL is proud to offer proven technology like CleanMe®, dust compensation, field replaceable optical chambers, multi-criteria heat algorithms and self-diagnostics which are trusted by installers around the globe.

Smoke Detectors - ADEMCO 5192 Series Low Profile Addressable V-Plex

The ADEMCO 5192 Series low profile, addressable V-Plex™ smoke detectors deliver state-of the-art features and benefits in a cost-effective package. These detectors are designed to provide open area coverage and are compatible with ADEMCO’s VISTA controls supporting V-Plex technology. An LED on the detector will blink periodically during normal conditions, remain on steady during alarm and cease to pulse if the chamber is out of acceptable sensitivity range

Features

• Low profile design
• V-Plex™ addressable loop device
• Automatic maintenance reporting
• Available with integral heat sensor
• Simple 2 wire installation
• Tamper resistant
• DIP switch or serial number programmable
• Lines on existing or conventional wiring

FireLite Addressable Fire Alarm Systems - FireLite MS-5012 Fire Alarm Control Panel with Built-In Digital Communicator

Features

• New Larger Enclosure
• Five programmable Initiating Device Circuits (zones).
  Zones may be programmed for:
  . Two-wire smoke detectors (Zones 2 & 3).
  . N.O. contact devices (pulls, heats).
  . Four-wire smoke detectors.
  . Waterflow operation (Zone 3 only).
  . Supervisory operation (Zone 4 only).
• One Style Y (Class B) Notification Appliance (Bell) Circuit (NAC).
• 1.0 Amp of Notification Appliance power.
• Relay driver outputs for alarm, trouble, supervisory and communication failure.
• Dual-line rotary- or Touch-Tone®-dial DACT interfaces to public telephone network (leased phone lines are not required).
• 12-Volt operation.
• Built-in voltmeter measures:
  . Primary AC line voltage.
  . Battery voltage.
  . Zone voltage.
• Surface Mount Technology.

FireLite Addressable Fire Alarm Systems - MS-9200 198-Point Addressable Control

Features:
SLC Loop:

* SLC can be configured for NFPA Style 4, 6, or 7 operation.
* SLC supports up to 198 addressable devices [99 detectors and 99 monitor or control modules ], including new addressable dual monitor module.
* SLC loop max. length 10,000 ft. (3,048 m) @ 12 AWG (3.25 mm2).

Programming and Software:

* Autoprogram and Walk Test features identify two or more devices set to same address.
* Keypad programmable on panel, with two user-defined passwords, plus an Autoprogram feature.
* Custom English labels per point may be manually entered or selected from an internal library file.
* Remote Acknowledge, Silence, Reset and Drill via MMF-300 modules and LCD-40 remote annunciators.
Notification Appliance Circuits (NAC’s):

* Dual Integral NACs, Style Y or Z (Class B or A).
* Silence Inhibit and Auto Silence timer options.
* Alarm, trouble and supervisory relays, standard.
* May be programmed for Steady, March Time, Temporal or California code (requires software P/N 73750 or greater).
* 3.0 amp NAC power, expandable to 6.0 amps.