Fusion Message Board

In this space, visitors are invited to post any comments, questions, or skeptical observations about Philo T. Farnsworth's contributions to the field of Nuclear Fusion research.

Subject: Re: Instrumentation - Fusor
Date: Nov 12, 7:23 pm
Poster: Gerald Morris

On Nov 12, 7:23 pm, Gerald Morris wrote:


>The first instrument is a virtual must have. It is a voltohmeter (VOM) It can be of the analog meter type or the more pouplar LCD digital readout type. (Radio Shack - $20-$60 range) This can be used to measure current and voltage (up to 1500 volts), or adapted to read even higher. This is needed to follow the fusor's power input requirements. Often, two individual meters are used on the power supply to obtain these readings. Still, during assembly a lot of voltage measurments and checks might be required.

I still think ye venerable Simpson Model 260 is the best voltometer for the money. It will handle up to 5kV AC or DC and 10A currents. Rich is damned right about the importance of reading the voltage at the HV feed on one's fusor. Even those of you using your home grown power supplies should read at the feed if you have the equipment. I toasted at least a 50 ohm 20W resistor today in my Universal Voltronics 5kV, 200mA supply today by relying on the instruments voltage and current meters instead of watching where the action is! I just hope that replacing the resistor will be all that is needed to get this machine back on line. I need the data and my prof doesn't appreciate having his equipment wrecked when his back is turned. It also behooves you all to use a current limiting device to avoid the kind of crap I went through today. I will not rely on the manufacture's overcurrent protection devices again!

>The second instrument is an incredibly valuable tool, but you can get along without it. This is, a theromcouple vacuum gauge - (TC gauge for short.)

>I highly recommend a good solid new instrument based on the DV-6M TC gauge tube.
>Those serious about neutron production must have this crucial tool.
> A good clear closeup of the DV-6M meter and its scale can be seen on Gerald Morris' web page. (URL given in his Nov 10th post.)
--Nice plug Richard.
>Richard Hull