Search found 1339 matches

by John Futter
Tue Jan 15, 2019 6:13 am
Forum: Neutrons, Radiation, and Detection (& FAQs)
Topic: How to figure out the specs of old Rigaku scintillation tube probe?
Replies: 20
Views: 813

Re: How to figure out the specs of old Rigaku scintillation tube probe?

Harald We use beam profile monitors at work to know the shape and position of our ion beams look them up they are a bent peice of wire that rotates within the ion beam tube and present a differing position target to the beam without taking out much beam energy so you can leave them in while running ...
by John Futter
Tue Jan 08, 2019 6:05 pm
Forum: New User Chat Area
Topic: Roots Pump
Replies: 2
Views: 134

Re: Roots Pump

Chris
Normally a roots type pump is used with an ordinary backing pump to significantly speed up the pumping speed
they are also used in industrial cutting lasers to circulate the lasing gas through an intercooler
by John Futter
Tue Jan 08, 2019 6:02 am
Forum: Please Introduce Yourself
Topic: New SoCal Effort
Replies: 7
Views: 309

Re: New SoCal Effort

No I was not allowed to ie no good reason to produce ionising radiation Although If I wanted to do it over a weekend with another staff member on hand to satisfy safety concerns I probably could. 'Recently I have been running high power carbon beams (Butane gas) in the ion source and ion currents of...
by John Futter
Mon Jan 07, 2019 6:20 pm
Forum: Please Introduce Yourself
Topic: New SoCal Effort
Replies: 7
Views: 309

Re: New SoCal Effort

Joe What makes you think that Garret only used a mechanical pump yes the operating point is above the lowest pressure that a mechanical pump can achieve but the pumping speed is almost zero. you need vacuums before you start of 10^-5 torr or better to remove as much crud especially water vapor from ...
by John Futter
Sat Jan 05, 2019 2:16 am
Forum: High Voltage - Fusor Input Power (& FAQs)
Topic: Liquid dialectrics
Replies: 2
Views: 149

Re: Liquid dialectrics

You really need to do a search first before asking this question here
It would have been ok in the new user chat area
by John Futter
Sat Jan 05, 2019 2:10 am
Forum: High Voltage - Fusor Input Power (& FAQs)
Topic: HV Divider
Replies: 7
Views: 517

Re: HV Divider

I would buy a box of VR68 5M1 series resistors from Vishay available from digikey etc
$0.28 each a box = 500 so about US$150 ish a box share with another member
each resistor is designed to cope with 10kV but this may be less due to actual dissipation limit of 1 watt --you work it out
by John Futter
Thu Jan 03, 2019 6:20 pm
Forum: Vacuum Technology (& FAQs)
Topic: Cleaning/Repairing Edwards E2M5
Replies: 13
Views: 638

Re: Cleaning/Repairing Edwards E2M5

The oil sight glass is o-ring sealed to the box
be careful it is easy to break it when attempting to remove.
Our Mch workshop @ work made a new one out of perspex when we broke one
by John Futter
Mon Dec 31, 2018 6:35 am
Forum: Fusor Construction & Operation (& FAQs)
Topic: Demo fusor build 2.0
Replies: 3
Views: 334

Re: Demo fusor build 2.0

please learn how to attach the correct size photos to your post so that they are stored on this forum and not some third party viewer site later many will want to see what you have done and if the viewer site you have selected has gone /you are not a member/payer anymore or whatever else causes web ...
by John Futter
Thu Dec 27, 2018 7:26 pm
Forum: Images du Jour
Topic: Canal Ray pictures
Replies: 19
Views: 1139

Re: Canal Ray pictures

CCP = capacitively coupled plasma
ICP = Inductively coupled plasma
by John Futter
Wed Dec 26, 2018 8:04 pm
Forum: Images du Jour
Topic: Canal Ray pictures
Replies: 19
Views: 1139

Re: Canal Ray pictures

Yes our 3 MeV accelerator is single ended and uses an Rf powered ccp in a canal type ion source ion source runs at around 2-3kV but this is on top of 3 million volts generated by the van der graff and then accelerated by the voltage gradient down the acceleration tube whose bottom section is earthed...