The model B7F is capable of either single or double pulse operation, by front panel control" (Rutherford, Manual B7F, 1960)
BRIEF SPECS
| Repetition Frequency | 5 Hz to 2 MHz |
| Amplitude | ±50 V max. into 50 ohms |
| Risetime | less than 14 ns |
| Falltime | less than 16 ns |
| Pulse Width | 100 ns to 10 ms |
| Pulse Delay | 100 ns to 10 ms |
| Attenuation | up to 50:1 |
| Ventilation | forced air |
| Power | 300 VA |
| Dimensions | 8-3/4" x 19-1/2" x 13" |
| Weight | 42 lbs |
| Technology | tube |
| Price (1960) | $ 920 |
This B7F-S pulse generator was manufactured by Rutherford in 1969 after the takeover by Computer Measurement Corporation (CMC) - see their announcment below. The CMC-label is just added to the original Rutherford front panel. I have the manual of one of it's family members B7B dated from 1960. So at the date of manufacturing it was an old design without transistor circuitry, although it used two pcb's. The B7F-S added the 'double pulse' feature and 'rise & fall time' control by adding one little pcb to the basic design. Also the lowest repetition rate was improved and rise & fall times had independent controls. The B7F-S is one of the highlight of my collection because with it's large 'R' labeled black and red knobs and the pilot lamp jewels it's like a piece of modern art!
CMC has acquired the assets of Rutherford Electronics Co., the nation's best-known producer of pulse generators. Rutherford will function as a division of CMC. CMC President John K. Rondou termed the acquisition 'the first major step in CMC's long-range expansion program, which includes the goal of providing a wide variety of test instruments for scientific and engineering research.' ... Rutherford, headquartered in El Segundo, Calif., was founded 15 years ago by Charles E. Rutherford, one of the pioneers of the pulse generator field. The company's 1964 sales were approximateley $1,000,000. Present management and personnel of Rutherford will remain with the company, Rondou stated." (CMC, Condensed Catalog, November 1965)
The restoration of this fine instrument was one of my greatest challenges. I purchased two instruments in less than fair condition from a local surplus dealer. He gave me a third (B7F) which was 'trash'. The front and interior of the one you see here was good with two exceptions: the aluminium outer chassis was cracked due to dropping the instrument (heavy power transformer) and the power supply pcb was badly 'repaired by a non-technician'. The second instrument had a uncracked chassis (but many scratches) but was 110 V AC only and with very bad interior. The third had a clean and unrepaired power supply pcb. So the way was clear: take the best parts from all and built one instrument from scratch!
The instrument in the exhibition has a renewed chassis (coated with silver baked enamel) and after replacing the gassy voltage reference tube and one 7119 with broken filament power-on was succesfull.
If you want to mix pulses from
two pulse generators you'll find some information here: Pulse Mixing Network (98k)
.
