Search found 109 matches

by Joe Gayo
Tue Jan 15, 2019 3:54 am
Forum: Images du Jour
Topic: Joe Gayo's Fusor
Replies: 20
Views: 7023

Re: Joe Gayo's Fusor

Based on looking at the pulse waveform from the amplifier with an oscilloscope I was able to setup a window discriminator (2.1-5.9V) to reject the majority of events that occur without a moderator. It does appear that most non-moderator events have a leading negative voltage spike and a subsequent >...
by Joe Gayo
Mon Jan 14, 2019 6:08 pm
Forum: Images du Jour
Topic: Joe Gayo's Fusor
Replies: 20
Views: 7023

Re: Joe Gayo's Fusor

I've done this test before but I re-ran this morning (detector in same relative position to fusor for all tests, 10cm) - 30 minute background with moderator: 24 counts No moderator / No activation oven (within 3m): 28 mTorr D2 35kV @ 10mA 90 seconds, 274 counts (note: pulse has leading negative comp...
by Joe Gayo
Mon Jan 14, 2019 6:31 am
Forum: Images du Jour
Topic: Joe Gayo's Fusor
Replies: 20
Views: 7023

Re: Joe Gayo's Fusor

I think we said the same thing ... with and without the moderator ...

I was proposing an additional test without Deuterium but thinking about it, that isn’t valuable

And if you are a forum moderator for 18 years, you will probably repeat yourself a lot
by Joe Gayo
Mon Jan 14, 2019 5:12 am
Forum: Images du Jour
Topic: Joe Gayo's Fusor
Replies: 20
Views: 7023

Re: Joe Gayo's Fusor

Richard,

I assume you are talking about tests with and without the moderator, then with and without deuterium in order to eliminate x-rays and electronic noise respectively.
by Joe Gayo
Mon Jan 14, 2019 3:39 am
Forum: Images du Jour
Topic: Joe Gayo's Fusor
Replies: 20
Views: 7023

Re: Joe Gayo's Fusor

I would rather wait until my setup is calibrated. I have a high degree of confidence that neutrons are being generated but an exact quantity (+/-20%) is more satisfying. In addition, I’m improving the signal processing of the neutron pulse in the meantime.
by Joe Gayo
Mon Jan 14, 2019 2:10 am
Forum: Images du Jour
Topic: Joe Gayo's Fusor
Replies: 20
Views: 7023

Re: Joe Gayo's Fusor

Thanks.

4-6 weeks will be a long wait for the bubble dosimeter, but worth it.
by Joe Gayo
Sun Jan 13, 2019 7:13 pm
Forum: Images du Jour
Topic: Joe Gayo's Fusor
Replies: 20
Views: 7023

Re: Joe Gayo's Fusor

CHM-11 Tube Adapter Box

HV Input w/ RC Filter (2Meg * 47nF)

Bias w/ 50Meg

AC Couple w/ 33pF
IMG_0800_sm.jpg
by Joe Gayo
Sun Jan 13, 2019 7:07 pm
Forum: Images du Jour
Topic: Joe Gayo's Fusor
Replies: 20
Views: 7023

Joe Gayo's Fusor

Pressure: 25mTorr (4mTorr base)
Voltage: 40kV (50kohm ballast resistor)
Current: 6mA

Detector: CHM-11 (1600V, 64x Gain, 3V Threshold)
Run CPM: 622 (Avg 5 min run)
Background CPM: 2 (Avg 30 min)
IMG_0811_sm.jpg
IMG_0810_sm.jpg
IMG_0871_sm.jpg
IMG_0806_sm.jpg
IMG_0803_sm.jpg
by Joe Gayo
Tue Jan 08, 2019 2:35 am
Forum: Vacuum Technology (& FAQs)
Topic: The Importance of TC Gauge Calibration
Replies: 13
Views: 9284

Re: The Importance of TC Gauge Calibration

Bruce,

Were did you purchase that readout display? (I noticed that Finn Hammer is a user on Fusor.net)

Thanks, Joe