Quantcast Figure 2-8.Grid operation in a remote-cutoff tube

Share on Google+Share on FacebookShare on LinkedInShare on TwitterShare on DiggShare on Stumble Upon
Custom Search
 
  
 
2-8 Figure 2-8.—Grid operation in a remote-cutoff tube. In view B, the control grid is at zero potential (0 volts). Just as in the sharp-cutoff tube, electrons leave the cathode and travel along the lines of electrostatic attraction, through the spaces between the grid wires to the plate. In view C, a bias voltage of -6 volts is applied to the grid. Because of the close spacing of the grid wires at the ends of the grid, electrostatic lines of force at the ends are effectively terminated. The lines of force can only pass between the widely spaced grid wires closer to the center of the grid. In view D, the same negative potential -20 volts) is applied to the grid that caused the conventional sharp-cutoff tube discussed earlier to go into cutoff. This voltage is high enough to terminate most of the electrostatic lines of force on the grid wire. But, because of the wide spacing between the center grid wires, some electrostatic lines of force are still able to pass between the center grid wires and reach the cathode. Conduction will still occur in the tube, but at a reduced level. If the grid is driven even more negative, lines of force will be blocked from reaching the cathode, except at the very center of the grid. As you can see, the remote-cutoff tube, by its ability to reduce gain (conduction), handles large signals without going into cutoff. A variable-mu tube such as a 6SK7 with -3 volts applied to the grid will have a transconductance of about 2000 (µ) mhos. If the grid is driven to -35 volts, the transconductance of the tube will decrease to 10 (µ) mhos. This same increase in negative-grid voltage would have driven a conventional tube into cutoff long before the grid reached -35 volts.


Electrical News
Ethernet Links Go Green
Everything that uses energy uses too much if it. Energy...
eetimes.com
EEVblog #658 – Mailbag
Mailbag Monday. Dave opens his mail Spoilers: Keithley 177 Multimeter...
eevblog.com
EEVblog #657 – Maker Faire 2014 Interviews
Some interviews from the 2014 Sydney Mini Maker Faire at...
eevblog.com
The Internet of Things Versus Slumlords
Smart thermostats are not only for the well-to-do. One group...
eetimes.com
IBM Watson Speeds Drug Research
IBM Watson moves from supplying known answers to tough questions...
eetimes.com
Samsung Funds III-V FinFETs in US Lab
Samsung is funding Penn State researchers working to fabricate III-V...
eetimes.com
LG, Samsung Debut Smartwatches, Apple Lurks
LG's G Watch R and Samsung's Gear S do little...
eetimes.com
Imagination Takes On Raspberry Pi
Imagination Technologies has developed its own version of Raspberry Pi,...
eetimes.com
California Smartphone Kill-Switch Law: What It Means
Do you understand the consequences of California's new smartphone anti-theft...
eetimes.com
9 Insights From Hot Interconnects
Facebook described its network switch, while experts picked apart flaws...
eetimes.com
Microchip in Pursuit of CSR
Microchip confirmed Thursday that it has had preliminary mutual discussions...
eetimes.com
Are There Marsquakes on Mars?
A 2016 mission will investigate the stuff under the surface...
eetimes.com
Friday Quiz: Forgotten T&M Companies
Remember the names of these test-equipment companies? Most are long...
eetimes.com
Rohm Opens MEMS Foundry Operation
Rohm Co. Ltd. created a foundry business at the six-inch...
eetimes.com
Touch Taiwan: Display Vendors' 10 Bold Forecasts
Display suppliers are in the know. The companies exhibiting at...
eetimes.com
Power Week: RF Charging Startup & Dialog Semi Team Up for Over-the-Air Power
This week, "over-the-air" power got a boost when RF charging...
eetimes.com
9 Notorious Automotive Electronics Recalls
It's been a banner year so far for automotive recalls,...
eetimes.com
Indoor Navigation: The Next Big Thing
Custom system-on-chip from parent company mCube enables Ten Degrees to...
eetimes.com
New UART to WIFI chipset will unleash low cost Internet of Things
WiFi infrastructure is everywhere which makes easier to make network...
wsnblog.com
Data Centers May Ride on ASICs
Firebox, a research prototype in the works at UC Berkeley,...
eetimes.com
 


Privacy Statement - Copyright Information. - Contact Us

comments powered by Disqus

Integrated Publishing, Inc.
9438 US Hwy 19N #311 Port Richey, FL 34668

Phone For Parts Inquiries: (727) 755-3260
Google +