Really basic transistor question

Started by Bob Engelhardt in sci.electronics.basics4 weeks ago 3 replies

I want to build a device that will take my phones off line. The phones are connected to a Vonage modem that (I'm sure) uses the POTS standard....

I want to build a device that will take my phones off line. The phones are connected to a Vonage modem that (I'm sure) uses the POTS standard. Which is 50v DC at "idle"/on-hook and 90v (RMS) 20 Hz superimposed on that for ringing. 90v RMS is 250v p-p offset by 50v is -75 to 175 p-p. Off-hook is 10v DC with low voltage audio superimposed on that. The phones on the line are all electron...


Biology 10th Edition Peter Raven (Test Bank)

Started by Anonymous in sci.electronics.basics4 weeks ago

solutions book team learngroups2019@gmail.com l e a r n g r o u p s 2 0 1 9 @ g m a i l . c o m learngroups2019(at)gmail(dot)com We...

solutions book team learngroups2019@gmail.com l e a r n g r o u p s 2 0 1 9 @ g m a i l . c o m learngroups2019(at)gmail(dot)com We just reply by email learngroups2019(at)gmail(dot)com (We do not deal with direct reply via groups google Please Do NOT POST/REPLY HERE, just email us at learngroups2019(at)gmail(dot)com We're a team for providing solution manuals & Teast Bank to ...


Biochemistry 8th Edition by Jeremy M. Berg (Test Bank)

Started by Anonymous in sci.electronics.basics4 weeks ago

solutions book team=20 learngroups2019@gmail.com=20 l e a r n g r o u p s 2 0 1 9 @ g m a i l . c o...

solutions book team=20 learngroups2019@gmail.com=20 l e a r n g r o u p s 2 0 1 9 @ g m a i l . c o m learngroups2019(at)gmail(dot)com=20 We just reply by email learngroups2019(at)gmail(dot)com (We do not deal wit= h direct reply via groups google Please Do NOT POST/REPLY HERE, just email us at learngroups2019(at)gmail(do= t)com=20 We're a team for providing solution manuals & ...


Basic Marketing A Marketing Strategy Planning Approach 18th Edition by William D. Perreault Jr. (Test Bank)

Started by Anonymous in sci.electronics.basics4 weeks ago

solutions book team learngroups2019@gmail.com l e a r n g r o u p s 2 0 1 9 @ g m a i l . c o m learngroups2019(at)gmail(dot)com We...

solutions book team learngroups2019@gmail.com l e a r n g r o u p s 2 0 1 9 @ g m a i l . c o m learngroups2019(at)gmail(dot)com We just reply by email learngroups2019(at)gmail(dot)com (We do not deal with direct reply via groups google Please Do NOT POST/REPLY HERE, just email us at learngroups2019(at)gmail(dot)com We're a team for providing solution manuals &


Auditing and Assurance Services Understanding the Integrated Audit 1st Edition by Karen L. Hooks (Test Bank)

Started by Anonymous in sci.electronics.basics4 weeks ago

\solutions book team learngroups2019@gmail.com l e a r n g r o u p s 2 0 1 9 @ g m a i l . c o m learngroups2019(at)gmail(dot)com...

\solutions book team learngroups2019@gmail.com l e a r n g r o u p s 2 0 1 9 @ g m a i l . c o m learngroups2019(at)gmail(dot)com We just reply by email learngroups2019(at)gmail(dot)com (We do not deal with direct reply via groups google Please Do NOT POST/REPLY HERE, just email us at learngroups2019(at)gmail(dot)com We're a team for providing solution manuals &


Switch for vaporizer

Started by Anonymous in sci.electronics.basics4 weeks ago 7 replies

I use this switch for a hot vaporizer. I noticed the switch get pretty warm when vaporizer is running. It draws 5 amps, but the switch is...

I use this switch for a hot vaporizer. I noticed the switch get pretty warm when vaporizer is running. It draws 5 amps, but the switch is rate at 3 amps. "https://www.dropbox.com/s/0zjo80p67eqbeui/3_Amp_Switch.jpg?dl=0" Does it look like any problems based on the picture? Andy


Interacting externally with a PC?

Started by Anonymous in sci.electronics.basics1 month ago 9 replies

Any suggestions on a no-brainer and safe way to get external input recognised by a PC please? Apart from a voice command approach. Or a solenoid...

Any suggestions on a no-brainer and safe way to get external input recognised by a PC please? Apart from a voice command approach. Or a solenoid to tap a key. For example a cheap commercial or easily built switch or momentary button with a USB plug at its end. That sort of thing. Terry, East Grinstead, UK


Lifespan of lithium-polymer battery

Started by Andy in sci.electronics.basics1 month ago 12 replies

What is an average lifespan for a lithium-polymer battery? I have one in my fitbit. Andy

What is an average lifespan for a lithium-polymer battery? I have one in my fitbit. Andy


Switch for USB cable

Started by Anonymous in sci.electronics.basics1 month ago 2 replies

This is an electronics question. :-) I have problems scanning documents. To get a scan to work, I have to unplug the usb cable (that goes...

This is an electronics question. :-) I have problems scanning documents. To get a scan to work, I have to unplug the usb cable (that goes from desktop to scanner) Then reopen my scanner app and then it scans. I could not find something that would let me stop/start the connection between the cable and scanner without actually unplugging it. I cut open an unused USB cable and found a ...


mutual capacitance?

Started by RichD in sci.electronics.basics1 month ago 36 replies

Looking at network theory and the duality theorems, why is there no mutual capacitance? i.e. electric flux linkages, symmetric to mutual...

Looking at network theory and the duality theorems, why is there no mutual capacitance? i.e. electric flux linkages, symmetric to mutual inductance and B flux. -- Rich


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