The First HP Commercial Products
Bill's prototype became the HP company's first product the HP 200A.
As shown in the wiring diagram below, two options with different frequency ranges were available: the 200A and 200B. A small modification of 6 resistors values resulted in different frequency ranges 35 to 35,000 cps for the 200A and 20 to 20,000 cps for the 200B.
All other specifications are common for the two units. A two-stage power amplifier with transformer-coupled output delivers 1 Watt into a 500 ohm resistance load. The output voltage is controlled ahead of the output amplifier from a front panel level control. The total harmonic distortion is lower than 0.5 %.
The HP 200B with rounded corners shown in this photo was hand built, probably in the second garage ( 481 Page Mill Road ) in 1940, and may have been handled by Bill and Dave themselves. It is so old, they do not even have a HP company logo yet. Units with this particular case style are very rare today
Texte de F5MM
