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Name: Andy L.
Status: educator
Age: 30s
Location: N/A
Country: N/A
Date: Sunday, May 05, 2002

My Van de Graaf generator is producing little or no charge. I know humidity is a factor, but what can I do to get better charges (bigger lightning streaks) Does the belt "wear out" and need replaced? Is there something I can tighten? Add dust to the room? How much humidity is too much? Is stagnant air better than circulating air? I want my demonstrations to be as dramatic as they can be.

1. Yes, the belts do wear out. We find that we must replace about every 15 months.

2. Your roller may be dirty. Clean them with toilet tissue or lens cleaning tissue and alcohol. Cotton swabs also work. It would be a good idea to clean the outside of the dome, too.

3. The larger the dome on the grounding sphere, the larger the spark.

4. Humidity above 90% usually causes problems. I have gotten nice sparks even during thunder storms with the windows open.

5. Dust is not recommended.

6. I have found no difference in air circulation.

---Nathan A. Unterman

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