Microwave Associates began life in 1952, having gained a licence to Bell Technologies transistor technology. The logo showing in one of the photographs is from the 1952 period. Microwave Associates designed and manufactured a number of "cartridge style" microwave silicon diodes, the well known 1N series began. It wasn't until 1960 that Microwave Associates began commercial release of their mesa junction diodes, sealed in glass, these being the 1N9xx series and I think there was also a 1N8xxx series that followed. Mesa junction semiconductors have a higher Q factor and lower series resistance than similar planar devices.
Made in USA
SHF Detector Diode
The more commonly available 1N series is well known (cartridge style) but I haven't seen one packaged like this before.
Suspected to be from the mid 1960's - 1970's era
I have had this device for "yonks" since my very early days in radio technology (1960's) but have no idea what specific equipment it was used in. My early days revolved around VHF-UHF and I suspect this detector diode is intended for use in the range 3Ghz - 10Ghz - I do remember this RF semiconductor diode was certainly quite something as most active devices at the time were vacuum tube based.
Unfortunately the diode type number is unknown
The diode is encased in clear plastic tubing, from which protrudes brass contact pins
The flexible clear plastic tubing has this printed in it, blue
MICROWAVE ASSOCIATES
The glass encapsulated diode can be clearly seen inside the tubing however I have looked EXTREMELY closely at the glass envelope and there appears to be no markings at all which may identify the diode.
I am not convinced this diode is ESD sensitive because the ESD packaging is actually for one of Microwave Associates more common 1N series cartridge diodes but while handling the diode I made sure I was ESD safe.
I have hunted around online (for a considerable period of time) and have not been able to find any device similar to this one, nor any description of this series from Microwave Associates.
I am offering this diode as a curio or museum piece, it is unlikely to be of practical use these days.
NOTE: Interesting packaging - the leads from the glass casing are welded to brass pins, this diode appears to have been designed as a "plug in" to the equipment.
This unused diode has ALWAYS been keep in the original anti-static packaging until I inspected it in an ESD safe environment.
