Ferris Model 18-D RF MicroVoltmeter, 8~210 MHz

This meter is designed to Generate and measure RF voltages from 8 Mhz through 210 Mhz in 7 ranges.  It has a finely made 0~150  stainless steel vernier tuning dial and an RF Voltage meter that measures 1.2 V FS.   Internal (400 and 1000 HZ) or External modulation can be used.   A tag reads "Property of US NAVY-173 NO.128128".   

There is an internal 5 tube oscillator/power supply and all of the controls are separately shielded and sealed internally, in order to provide added RF isolation.  The external case is made entirely of aluminum.  In fact, with the exception of the handle and a few jacks, the case and multiple sub-chassis are of aluminum.

The meter is untested and useful for prop & set or museum purposes.

We were unable to find much information regarding the The Ferris company, which was located in Boonton, NJ.   (Coincidentally, Boonton was also home to the Boonton Radio Corporation which was established in 1934.  Boonton Radio Corporation was purchased by Hewlett Packard in 1959.)

The Ferris Corporation was founded by Malcolm Ferris in the 1930s, and the Patent filing dates on the MicroVoltmeter are 1937 and 1941, which would put the manufacture date at a time after 1941.   Malcolm Ferris lost a defense of the validity of one of those patents in 1946.

This from Antiqueradios.com forum:

"Ferris was the top name in signal generators in the 1930s, until Malcolm Ferris died and his widow brought in a new manager. As a cost-cutting measure he fired all the engineers, who promptly formed a new company, Measurements Corp. Ferris lasted into the 1950s at least, but Measurements became the king of signal generators, with competition from General Radio.   You can probably find date codes on the internal parts and tubes."---A. Douglas Jan 17, 2006.

 Cosmetic Defects of note:

• Some paint removed around one front screw-hole
• paint flecked from various spots on the case