Analog Devices	AppCAD from HP
Advanced Power & Microsemi	Boin
Dönberg Electronics	Farnell Electronic Components
Hittite Microwave Corp	International Radio
Ladder Filter Design	Maxim Integrated Products
Microchip Technology Inc	Minicircuits
Northern Connectors Electronic Components
NXP Semiconductors	RF Cafe
RF Parts	Virtual Valve Museum
Wellbrook Communications	Wenzel/Documents/Circuits

Hubble Heritage Gallery	Hubble Web Site
NASA Jet Propulsion Laboratory	Seattle Robotics Society

Electronic Design News	IET
Microwaves & RF	RF Design