Shielding -- keep the signal inside -- or keep an external
signal from getting in.
Commonly supplied in colored pairs, as they are commonly used
for speaker outputs on amplifiers. You can buy them all in one color,
or in mounted pairs or whatever, but the most readily available are in
red/black pairs. Aside from the red and black, in good quality ones,
such as those by Greyhill, I also have some green and blue ones.
Here is what Graywhill's binding posts look like:
note that tehy come either with individual panel insulators, or ones
which hold two at the standard 3/4" spacing. (For that matter, I know
that they at least once had triangular patterns of three as well.
Downloading the data sheet, I no longer see the triangular three post
base insulator. But these were perhaps twenty years ago. :-)
From other makers, I have also seen yellow and white ones.
Others, once made by General Radio, were available in three
colors -- red, black, and bare metal. The latter was used as a ground,
the black was often right next to it with a sliding link to allow
grounding it or not at need, and the third was red, which was the hot
But these look like the poor quality ones which were once sold
by Radio Shack -- and those would have been sold with the assumption
that they would be used as speaker terminals, thus the red and black
pairs. Radio Shack also offers (at least on their web site) some better
quality ones as well.
I just went searching on Radio Shack's web page, and found this
These look very much like the ones which were in the device under
discussion. They are sold in packs of two pairs -- two red and two black.
Perhaps to even out clumping? Was there no carbon powder in
contact with the rods?
Note that carbon granule microphones in use tended to clump, and
had to be bumped to break up the clumps. Think of the old telephones
(which used carbon granule microphones), and how occasionally they would
produce weak sound. If you bumped the microphone end of the handset
against a table it would break up the clumping and improve the sound
Could be -- or if it was unique -- or one of only a few, the
distinctive color pattern could explain what it was to those who were
presumed to need to know. :-)
A complete copper shield does not have to be grounded to block
RF. It can be advantageous to ground it if you want to control buildup
of static voltages, of course.
Or -- it could be that there was a connection from the black
binding post to the copper case -- which would serve as the requested
reason for the two colors.
It was fabricated by someone comfortable with soldering irons...
Possibly one is not insulated from the case, that'd be the 'black'
The powder makes a better connection to the electrodes and keeps
the assembly from breaking connection.
I'm guessing this was a dump resistor to make a HV capacitor safe;
when working on HV electronics, it's common to use a shorting chain on
a long wood pole as the final step before getting your hands into the
works for maintenance, but sparks are annoying (and molten chain bits
have to be chiseled off the insulators...) so there's usually a slow
discharge resistor. I've seen long vinyl hoses filled with slightly
conductive buffer solutions, with multikilovolt power capacitors.
The likely voltage range for this construction is ~1kV or less.
Calibration and stability aren't important in this use, but
heavy conductors and failsafe conductivity are.
O.K. The copper makes a good electrostatic shield.
If the powder is truly carbon, it *could* be some kind of
vibration transducer -- similar to a carbon microphone -- where
vibration changes the resistance. Perhaps something for detecting
footsteps in the forest or something similar.
I presume that there were no experiments with measuring at the
terminals prior to disassembly?
Posting from rec.crafts.metalworking as always:
2149) Looks like something designed to count out the number of lengths
of some product -- perhaps cheese or butter. The device with a
handle below it would appear to be for scribing a cutting line
for thicker things, or for cutting fully through thinner things.
Since the smaller one seems to increment in steps of 2, I would
guess that these are units of weight -- ounces or pounds.
2150) Hmm ... the '$' seems to be upside down as shown, which
suggests that it would be used while standing on the item,
perhaps to mark the end of a length of log as accepted.
How long is the handle? It sort of looks like a sledge hammer,
but I'm not sure.
2151) Perhaps for forming round cakes of soap or something similar,
with the adjustment screw tuning for the final size.
2152) Drive it into the end of a section of log, then screw it in to
split the log.
2153) Where is the hole in the spike? On the end? (Not clear from
the photo). If so, I might think that it would be used in a
church for installing candles in candelabras and lighting them
with a thin wax taper running through the spike. (I don't see
the sliding part to adjust the extension of the taper, however.)
2154) A carrying case for a badly unbalanced dumbbell set. :-)
Now to see what others have suggested.
Someone sent me the photo so I don't know exactly where the hole is but was
told that there is one.
Tough set this week but most of them were answered correctly, still not sure
about number 2152, the rest of the answers have been posted here:
Hey Rob. Here's a better video of a Tesla coil in action. The guy is
in a Farraday suit holding two fluorescent tubes in his hands. Tell
me _that_ guy isn't brave!
I also have some strong doubts about the item that you listed as a
cigar holder. Yes, it has strong similarities to the cigar holding
patent link your provided, but there are enough functional differences
that I don't see how it could be one. The one pictured in your quiz
has a widening 'mouthpiece' and no provision for a foot or anything to
keep it from rolling over if put down. The widening mouthpiece is
very problematic for something meant to inhale through - something
with appreciable resistance. The tiny hole in the hollow pointed barb
that pierces the cigar would have very little air flow to start with,
and that coupled with a widening and fairly large opening where
ostensibly someones' lip would be, would make the draw very, very
difficult. When people inhale through something with resistance, they
purse their lips, not hold their lips wide. Have the owner of that
holder try to smoke a cigar through it and I would bet dollars to
donuts he will confirm my suspicions.
By far the best use of Tesla Coils are all the people using them to play
Like this one here where they are playing the US national anthem on the
Or this one where they played the Star Wars Imperial March on one of those
TV talent contents
Well, a trumpet has a big mouthpiece, and the player purses his lips
inside. However, smoking that way could leave stains around the lips,
something I doubt the inventor would like. The invention had a
mouthpiece that fit into the metal tube.
The invention had a bulb to catch liquids. The mystery item has none.
The parts of the invention unscrew for easy cleaning. The mystery item
doesn't appear to be screwed together.
45 215 looks little closer, but still substantially different.
I wonder if the mystery item was made to let somebody smoke a cigar for
five minutes and put it out without having it stink if he didn't relight
for a day or so. As smoke is drawn through a cigar, water and oil
condense in the tobacco. If you put it out and carry it around, it will
stink as those oils get old. The mystery item could keep smoke from
condensing in the tobacco by drawing it through the probe, near the
Drawing the smoke through the length of a cigar cools it. The big brass
tube would be a way to cool smoke drawn from near the tip. The fatter
the tube, the slower smoke travels, and the more time it has to transfer
its heat to the metal. There may have been a mouthpiece that slipped
into the end of the tube.
What trumpet player inhales through it? The PSI would be a function
between the relative sizes of the two ports. On any of Rob's posts we
could always surmise that a piece is missing to make our guesses
Is PSI pressure? Pressure would be atmospheric pressure minus losses
from restrictions. Those losses would vary according to flow. The
losses of drawing a puff of smoke through a cigar and through a
wire-sized orifice are likely to be small.
I put my finger over the little end of my trumpet mouthpiece, put my
lips into it, and puffed in, moving my finger enough to let air leak
with resistance. It worked fine. If I smoked a whole cigar that way, I
might need to wipe away a ring around my lips.
I seriously doubt if any real smoker would even consider such a thing.
One of the most important, but most overlooked (or ignored) aspects
of smoking anything is, it's something to stick in your mouth. :-)
Hope This Helps!
The one in the patent has a screw in mouthpiece, it's possible that it's
missing from the one on my site, I'll ask the owner if the open end is
If it was set down in an ashtray, it wouldn't matter if it was on its side
or not, I don't think it was meant to be put down on a table, same with the
old cigarette holders.
I'll also ask how big the hole is, the patent mentions "a number of holes",
the owner mentioned "a hole" in an email, but may have mistyped.
I think that cigar holder is the correct answer but will be happy to look at
any evidence that points in a different direction, I can't think of anything
else that it could be used for. I'll let everyone know when I hear back
from the owner.
With a trumpet mouthpiece, I have found it easy to suck air against
resistance with my lips in rather than around a mouthpiece.
45,215 (1864) is an earlier patent. It has no bulb to collect liquids.
It has a place for a piece of sponge soaked in camphor, a sort of
Your patent says one advantage is that because the smoke is drawn from
near the burning tip, the rest of the cigar is not spoiled if you decide
to save it.
I think that's the big advantage of the mystery item. In addition, the
large tube would cool the smoke. Any condensate could easily be wiped
out of a tube that large, long before there was enough to run. So who
needs a bulb or a sponge?
If anyone happens to have the book "Mikatin" by Juha Vartiainen, item number
371 in it is this cigar holder. The title on the cover is actually
"M?katin", it's an excellent 'what is it?' book from Finland, but hard to
find in the U.S. The photo in the book makes the holder look a little
different than the one on my site, in the book the black stem looks long and
thin, about 1/4" diameter, with a small round hole in the end, similar to
what you might find in a pipe mouthpiece.
The shadow on the photo on my site makes the stem look thicker, and wider at
the end. I can't post the photo in the book because of copyright issues,
but I'm sure that most people who saw it would agree that the small hole in
the mouthpiece would work well for smoking a cigar with this holder.
Here the DOT talks about maintaining trails by splitting rock with
drills and wedges.
It mentions shale, shist, sandstone, limestone, marble, and harder
rocks. The metal missing from 2152 makes me wonder if it's a screw
wedge for splitting some kinds of rock.
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