Electronics Forum / Basics / July 2006

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Is all telephone cable wiring of the stranded variety?
I would like to get some and splice into it to, but I would prefer not
to work with stranded wire.

Would a computer designed to use high-voltage, low-amperage have any
advantage over conventional computers? In this high-volt, low-amp PC,
all of the components [motherboard, cpu, memory, video system
(including the monitor), sound system (including the speakers)] rely on

I bought some ECS -100 i MHz clock oscillators to use as an external
clock to set a cutoff frequency in a Maxim lowpass filter (MAX281).
If I am reading the Maxim specs right, the oscillator's output voltage
is too low. The notes say that when using an external oscillator, "the

I use a Fluke 187 to test battery Ah and Wh capacity and currently, it
involves opening the csv file in Excel and calculating the area under
the curve using summation method.

Can someone look at:
http://electronics.howstuffworks.com/telephone5.htm
Do you think this will really work?
Any advice on how to get the 9 volts?

Imagine you have a vehicle that receives up to ten amps from a
generator, and with the generator off you need a blocking rectifier to
keep the 12 volt battery from discharging into the generator windings,
so you decide to use the  body diode of mosfet as the blocking

Would a computer designed to use high-voltage [around 10,000 volts],
low-wattage [around 0.000001 watt] have any advantage over conventional
computers? In this high-volt, low-watt PC, all of the components
[motherboard, cpu, memory, video system (including the monitor), sound

Hi, i have a square signal, with positive at 15V, and negative with
-15V, and i will like to convert this signal so that 15V will be 15V,
and the -15V will be 0V, to do this i have uses an op482 as omparator,
the configuration is this, +IN = -5V, -IN = Square wave, V+ = 15V, V- =

I am working on a power supply. The transformer is getting hot after 30
minutes of use. I can touch it , but not more then a few seconds in a row. I
guess this is because of too much current.??
I use a 120v to 25v AC transformer, to a Bridge rectifier, then to a 2000uF

Can you make an analog multiplier with an operational amplifier or a
biased transistor?
Thanks.

i have a "home" charger that outputs 1A 5V mini usb for my pda (it
camed with the pda)
Now i need to charge it in the car and i have an older charger mini usb
5V too, but i believe it has less output Amp.

I'm trying to measure some small current (probably 25 mA) using a Fluke
75 Series II multimeter.  I have the black probe in the COM slot and
the red probe in the 300 mA slot.  Then I connected the red and black
tips to the same node of my circuit and turned the knob to Amperes DC.

Hi, i have a square signal, with positive at 15V, and negative with
-15V, and i will like to convert this signal so that 15V will be 15V,
and the -15V will be 0V, to do this i use an op482 as comparator, the
configuration is this, +IN = -5V, -IN = Square wave, V+ = 15V, V- = 0V,

I am using MATLAB to do some simulation work on MIMO-OFDM. But to get
simulation results from my computer, I almost have to wait for a whole
day. This bother me a lot. I wonder if anybody has other faster
simulation methods. Thanks alot.