HP3320B Frequency Synthesizer

The HP3320B provides a dial-select able, low distortion, output frequency from .001Hz to 12.9999MHz over 7 select-able ranges. The frequency is derived from 1 precision frequency source through synthesis technique. At the same time, the output is controlled through a 3 dial select-able attenuator that provides a 50 ohm referenced dBm output that covers from 26.99dBm to -69.99dBm of output at less than .1% distortion. The max output voltage into 50 ohms is 5v. This early 1970's vintage unit was still cutting edge technology at the time. So the key attributes: Precise Frequency Selection, Low Distortion, and controlled / referenced output voltage! This is still a winning combination!

[@txkflier]

I used to calibrate both of those. I worked in a US Army calibration lab for 37 years..

[@bap8guy]

Wish I could have spent a few hours eith you calibrating this one, maybe I could have learned a few things. It is a very accurate unit in frequency and amplitude. It is big and heavy, but that has to be expected considering it’s age. Pretty much cutting edge at the time. Still very powerful now.

[@fr6885]

Hi. I saw a vid of yours from last year about a VIZ 707 dual power supply. I have a 707A that I have uses most everyday since '83. Now it needs some repair. I saw you had a schematic for the 708. Can you please provide a copy or tell me where I can find one for my 707A. i will check back here periodically. -Thanks!