Cell Phone Amplifier
I need a parts list and schematic
to build a cell phone amplifier to
connect to standard headphones.
#8121 James Moore
Powering a Hydrogen Generator
I’m building a HHO generator
and am trying to figure out the best
way to power it, keeping the power
usage low. A high voltage, low amp
method like using a Tesla coil might do
the trick. Any ideas to help me figure
[#6124 - June 2012]
I am looking for a positive
temperature coefficient motor starter
for a compressor. Or, I need help using
different parts such as a single pole
contactor/relay for a hard start.
The part I want to replace has the
following number: RF-6850-18, and
consists of a PTC starter and an overload protector. Can I replace this with
a hard starter contacter?
I can photocopy the schematics
and email anyone who can help me.
universal replacement. The "hard start"
kits you can get are nothing more than
a standard PTC starter, overload
protector, and capacitor stuffed into a
housing. The one time I tried one of
those, it failed within a few weeks.
If you want to try rolling your own,
the schematic in Figure 1 is said to
work although I've not personally tried
it. Digi-Key, Mouser, and other
electronics distributors carry a
selection of PTCs and bimetal circuit
protectors that could be used.
Audio Sound Spectrum
Is it possible to take the sound
heard in the frequency range of 0 to
40 kHz and space it evenly into the 10
Hz to 20 kHz range? I want to hear
what a dog hears but in the human
range. I know this will make people’s
voices sound funny, but how would
this be done and is there such a
device? Is there even a mic for that
upper range of up to 40 kHz?
#8123 Robert Spencer
#1 Go to any well stocked refrigeration supply house and ask for a
universal compressor starter.
This will be a device with leads.
(I have no idea what's inside.) Connect
it as shown on the package, removing
the existing starter device.
These things work every time. Be
sure to leave any original thermal
protective device intact.
They can also be used on small air
compressors that use PTC devices as
Connecting an Old Printer
to a Current PC
I have an IMP- 24 printer with a
Centronics interface. I would like to
print to it from a Windows 7 or XP
computer using some form of Basic. I
have VB and Visual Studio 2010
Ultimate. However, there seems to be
no drivers for this old printer. Is there
a way to address LPT1 from Visual
Basic or Visual C so I can send the
data to the printer directly without
going through the operating system?
Lake Forest, CA
#2 I've bought PTC starters for
refrigeration compressors from www.
repairclinic.com on a few different
occasions. A local appliance shop
with a parts counter should be able to
supply them too, either OEM or a
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attempted by qualified individuals.
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