Glenn Robb Visit to France

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Paris au Mois de Mai


At the beginning of May, Glenn and Tania Robb arrived in France to visit Paris and to start a collaboration between and



Mixing Business With Pleasure

Among the many social activities we enjoyed with Glenn and Tania in Paris, there is one which fit perfectly with the HP Memory Project's overall objective, and which could be told on this web site:


The Most Wonderful Gift Ever !

HP 200B "Rounded Top-Corners," A Gift from Glenn Robb
NOW the Oldest Showpiece of the HP Memory Collection



Glenn insisted on offering the oldest instrument of his own collection to add to ours the most symbolic instrument ever built by Hewlett and Packard: A 1940, "Rounded Top-Corners," HP 200B Audio Oscillator.

Needless to say that since its birth, the HP Memory Project has never received such a contribution!

This HP 200B enlarges the historical window covered by the HP Memory collection to the birth of the company. Back to a time when Bill and Dave had not even created a company logo for their products.





Pre-1941 Name Plate prior to introduction of an HP Logo

HP 200B
History Resources


Among the many, and sometimes divergent, stories trying to reconstruct the chronology of Bill & Dave's early Garage production, the deepest and most serious work was made by Kenneth Kuhn. The result of his work is a 13 page PDF document, available for download from his web site. From the Home page, click-on "Dating Vintage Instruments," then download the document: "vintage_hp_oscillators.pdf."

According to Ken's analysis, this HP 200B was hand built, probably in the second garage ( 481 Page Mill Road ) in 1940! It is so old, they do not even have a HP company logo yet.

The picture shows a close-up of the name plate of the HP 200B, Serial Number 187, gifted by Glenn. This nameplate style was used from the earliest oscillators up to 1941, when the new HP logo was introduced.



HP Memory Collection Enrichment

This extraordinary gift completes the vintage part of the HP Memory Project collection, complementing existing artifacts such as an original instruction manual for the Model 200 series of Audio Oscillators, as well as the original November 1939 issue of the ELECTRONICS magazine in which Bill & Dave made their first add to promote the HP 200B sales.

The picture below shows the four members of the HP Model 200 series now in the collection. They are the most representative showpieces of HP's very early production. Many other variations of the original HP 200 circuitry were built after these originals. They are also in the collection, and are discussed in various chapters already on line on this web site:

  1. Company History & Facts, The Beginning
  2. The very first: Audio Oscillators
  3. Early Signal Sources
Click-in for High-Resolution Display = 4000 x 1500 pix @ 300 ppi

HP 200B - with Pre-1941 Logo, "Rounded Top-Corners"

HP 200B - Post-1941, Rectangular Case ==== HP 200B Rack Mount with Post-1946 Logo ====== HP 200C with Post-1941 Logo



Cover of the Original Instruction Manual

Original, 1943 Instruction Manual
for the Series 200 Audio Oscillators


Click on picture or link below for a PDF (2.5 Mb) of the original instruction manual published in 1943. The manual include schematics, parts list, and chassis layout of the four different models produced by HP in 1943.


Instruction Manual for Audio Oscillators HP Model 200A, 200B, 200C and 200D .





First Publicity effort by HP in "ELECTRONICS" - November 1939, page 95
Issue available in the Memory Project Collection




More Information on Original Bill Hewlett's Invention

The two documents below give in-depth information about the Bill Hewlett invention, which mainly consist in using a light bulb in the feedback loop of an oscillator to stabilize its output level.


I.R.E. Article - October 1939

PDF of IRE Article,
Proceedings of the I.R.E. - October 1939

By: F. E. TERMAN, Fellow, I.R.E., R. R. BUSS, Student, I.R.E., W. R. HEWLETT, Associate, I.R.E., AND F. C. CAHILL, Student, I.R.E.

Click on picture or link below for a PDF (1.5 Mb) of the I.R.E. article published in 1939.

Some Applications of Negative Feedback with Particular Reference to Laboratory Equipment.





US Patent 2,268,872

By: William R. HEWLETT, Palo Alto California



Click on picture or link below for a PDF (330 Kb) of the original document, filed in 1939, and patented in January 1942.







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