Schematics for Spectech ST-360

This area is for discussions involving any fusion related radiation metrology issues. Neutrons are the key signature of fusion, but other radiations are of interest to the amateur fusioneer as well.
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Dennis P Brown
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Real name: Dennis P Brown
Location: Glen Arm, MD

Re: Schematics for Spectech ST-360

Post by Dennis P Brown » Sun Mar 12, 2017 5:52 pm

Well, one leg of the diode chip is bad (reads open for a fraction of a second then starts to conduct and show a 0.7 volt when it should read open.) So, if the diode took a hit, then it is very likely U-15 is bad (just received new U-15 chips but the diodes will be awhile before they arrive.)

The photo-multiplier does not detect neutrons significantly above the noise so, it isn't suitable.

The water cooling of my fusor chamber works great and keeps it fairly cool!

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Dennis P Brown
Posts: 1714
Joined: Sun May 20, 2012 2:46 pm
Real name: Dennis P Brown
Location: Glen Arm, MD

Re: Schematics for Spectech ST-360

Post by Dennis P Brown » Wed Mar 15, 2017 2:35 pm

Replaced the diode voltage clamp (micro-soldering while work under a microscope!) and the ST-360 works well with a scintillation detector (through, maybe a bit more noisy now.)

However, can't get it to work with my neutron tube - while I have a cap between the ST-360 (built into the voltage divider) and the applied power for the neutron tube (the voltage divider lowers the total voltage the ST-360 cap see's to around 1200 volts) my ST-360 signals a system failure when I go above 1750 volts on the neutron tube.

Will have to do more work to see if it is tube related or the ST-360.

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