Search found 124 matches

by AllenWallace
Tue Dec 06, 2016 6:48 am
Forum: Other Forms of Fusion - Theory, Construction, Discussion, URLs
Topic: Sources of pyroelectric crystal (LiTaO3 and LiNbO3)
Replies: 4
Views: 3235

Re: Sources of pyroelectric crystal (LiTaO3 and LiNbO3)

When buying pyroelectric crystals, you need for them to be Z-cut. Crystals used for SAW filters are cut at an angle and won't work for your purpose. They also may be treated so that the surface charge doesn't accumulate. Your best bet is AO modulators or Q switches. eBay currently has these priced u...
by AllenWallace
Mon Nov 14, 2016 12:43 am
Forum: High Voltage - Fusor Input Power (& FAQs)
Topic: HVSafety Circuit for comments
Replies: 7
Views: 4457

Re: HVSafety Circuit for comments

Please realized that there are safe and unsafe methods of measuring fusor current and voltage. Do have a proposed schematic to measure I and V?

We keep our fingers away from the hot stuff but yet we need instrumentation what requires us get close to with our fingers and eyes.
by AllenWallace
Tue Aug 30, 2016 2:58 am
Forum: Images du Jour
Topic: radioactive food?
Replies: 3
Views: 1735

radioactive food?

I didn't bother turning on my Geiger counter.
IMG_2103.jpg
IMG_2103.jpg (42.8 KiB) Viewed 1706 times
by AllenWallace
Tue Mar 01, 2016 2:54 am
Forum: Fusor Construction & Operation (& FAQs)
Topic: PEM fuel cell deuterium generator
Replies: 32
Views: 25242

Re: PEM fuel cell deuterium generator

Really nice! Are you going to put in a float switch or equivalent which will allow auto-demand?
by AllenWallace
Fri Feb 19, 2016 4:24 am
Forum: Fusor Construction & Operation (& FAQs)
Topic: Oakland University Low Powered Fusor Update
Replies: 11
Views: 7624

Re: Oakland University Low Powered Fusor Update

This looks very nice! I suggest you hook up your vacuum gauge directly to the pump and determine the pump pressure. This will allow you to discover if your high pressure is due to a pump limitation or a chamber leak. Please be careful about implosion. I don't see any shield about your vacuum chamber...
by AllenWallace
Sun Dec 06, 2015 3:55 am
Forum: Vacuum Technology (& FAQs)
Topic: Failure to vent a rotary vane vacuum pump?
Replies: 1
Views: 1924

Failure to vent a rotary vane vacuum pump?

I know that the pump oil will eventually suck back up into the vacuum chamber if you fail to vent the system. I've seen a turbo pump with oil in the outlet port. The question I have is: how quick does this happen? Minutes? Hours? Days? if oil floods the vacuum system and you turn on the pump, will t...
by AllenWallace
Tue Jun 03, 2014 4:04 am
Forum: Fusor Construction & Operation (& FAQs)
Topic: Dangers of A Deuterium Cylinder
Replies: 11
Views: 5362

Re: Dangers of A Deuterium Cylinder

Have you considered the PEM fuel cell method of generating D2? Cheap and safe compared to a bottle of gas.
-Allen Wallace
by AllenWallace
Thu Jan 23, 2014 4:18 am
Forum: Vacuum Technology (& FAQs)
Topic: Thermocouple gauge
Replies: 15
Views: 4462

Re: Thermocouple gauge

No you cannot use difference gauge controllers unless they are specifically matched to the tube type. See http://www.belljar.net/tcgauge.htm . All the tubes referenced in the article have the same octal connector, but have very different electrical specifications. FYI, you can use a variable power s...
by AllenWallace
Tue Dec 03, 2013 3:47 am
Forum: High Voltage - Fusor Input Power (& FAQs)
Topic: Measuring Voltage on a Computer
Replies: 6
Views: 2350

Re: Measuring Voltage on a Computer

I recommend a $29 USB DATAQ device. You get 10 bit resolution from -10 to +10 volts with a Visual Basic interface.
see http://www.dataq.com/products/startkit/di145.html
For the high school students out here, they give them away free...
by AllenWallace
Sat Nov 23, 2013 5:05 am
Forum: Vacuum Technology (& FAQs)
Topic: Getting lower pressure with Elite Z oil?
Replies: 1
Views: 778

Getting lower pressure with Elite Z oil?

How much pressure difference would a typical rotary vane pump achieve if it used Elite Z rather then grade 19 oil? It's 2X in price, Double distilled synthetic hydrocarbon oil. The vapor pressure of EZ oil is 10-7 torr compared to 10-5 torr, but does that make a difference in a pump that can only ge...