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Registered Member #56
Joined: Thu Feb 09 2006, 05:02AM
Location: Southern Califorina, USA
Posts: 2445
the first one looks like a piece of sch80 pvc pipe with a film of blue pvc solvent weld glue across another piece inside it.
The second is a long exposure of a red HeNe and some blue LEDs... The HeHe is being relected off a speaker onto a moving screen. The leds were dragged throught the exposure.
Registered Member #10
Joined: Thu Feb 02 2006, 09:45AM
Location: Bunbury, Australia
Posts: 1424
WRONG (it was schedule 40) Well OK you were sorta right... Yes it was a 4 inch TC secondary. The end cap was a little oversized so extra lake of PVC solvent. The irregular outside rim was masking tape to hold the wire end.
Second photo is half right. It is a diode laser (not HeNe) on a long exposure. The blue lights are 4 LCD screens of a power supply. Any other suggestions as to how the pattern was made rather than a speaker?
Registered Member #56
Joined: Thu Feb 09 2006, 05:02AM
Location: Southern Califorina, USA
Posts: 2445
No fair adding tape arround the pipe to confuse me on the wall thickness
I thought the red seemed a little too dark to be your hene, you almost had me thinking the blue was your argon, but I decided that that was just too blue.
As to the pattern... It is much to regular to have been moved by hand... And the camera couldn't have been moving that much since the blue is pretty much strait... And I doubt that you found a way to move the background to make that pattern... Were you shining it off a spinning mirror at some weird angle?
Registered Member #312
Joined: Mon Mar 13 2006, 01:50AM
Location: Georgia, USA
Posts: 27
... wrote ...
kind of amazing... That whole bag of ferrite beads, the whole lot of them after being wired up into a module costing soo much, is like 5% of a floppy disk
THe same seller now has an auction for 200 milllion cores (!!!), so now you CAN build that floppy disk emulator!
wrote ...
i just gutted a SMPS, and I found some slightly larger ferrite beads (2mm OD) on the leads of some dual diode. see if i can get some pix later... what are they for?
2mm appears to be over twice the diameter of mine, though earlier core memory may have used even larger cores.
But for a SMPS or most applications where a bead goes around a component lead, it's meant as a lossy inductor, to reduce the RF interference generated by the fast switching of the diode. I believe it's a somewhat different kind of material, still magnetic but with different properties than that used for core memory. If you google ferrite core and powdered-iron core you can find descriptions of materials used for various types of inductors and transformers.
Registered Member #10
Joined: Thu Feb 02 2006, 09:45AM
Location: Bunbury, Australia
Posts: 1424
... wrote ...
As to the pattern... It is much to regular to have been moved by hand... And the camera couldn't have been moving that much since the blue is pretty much strait... And I doubt that you found a way to move the background to make that pattern... Were you shining it off a spinning mirror at some weird angle?
The beam from a 5mW red diode laser is reflected by a mirrror on an instrument recorder amplifier that I found while dumpster diving at the physics Dept. This would normally drive a pen on a moving roll of paper (like a seismograph). It is 1981 vintage and has offset, gain and calibration controls. Full scale deflection seems to be about 0.1V and frequency response seems to go up to about 70Hz. Sadly I didnt pick up the second one.
The unit is fed from my frequency generator at about 70Hz and the result is a horizontal stripe. The circular motion is simply me rotating the camera by hand with a 1 second exposure. This brings out the sine wave character and also shows some additional sine wave superimposed on it.
Registered Member #56
Joined: Thu Feb 09 2006, 05:02AM
Location: Southern Califorina, USA
Posts: 2445
Well there is that red thing in the trees... That is new Looks like a personal flotation device to me
The bark on that pic and on the one of you in front of the exploding cap bank looks just like the ones in my back yard... Maybe you got some of the American diseased ones?
Registered Member #10
Joined: Thu Feb 02 2006, 09:45AM
Location: Bunbury, Australia
Posts: 1424
The mystery red object was a can being shot 15 feet out of my latest can crusher. It was positioned so that the base was level with the center of the work coil so it will fire the coil in the air. The can is shortened however as shown in the photo.
Next mystery photo is a bit easy but a full explanation is needed.
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Mystery Photos from TDU
Well OK you were sorta right...
