Search found 71 matches

by Finn Hammer
Mon Nov 20, 2017 9:27 pm
Forum: Images du Jour
Topic: Fusor progress, Finn Hammer
Replies: 25
Views: 8401

Re: Fusor progress, Finn Hammer

edit: It is late, getting units all mixed up, gotta go to bed But my goal would not be to increase counts per minute, it would be to shorten the pulsewidth. 500µS pulsewidth would allow (edit: 12000) counts per minute, and since they probably will not come flowing like off a clock generator, fewer. ...
by Finn Hammer
Mon Nov 20, 2017 9:11 pm
Forum: Images du Jour
Topic: Fusor progress, Finn Hammer
Replies: 25
Views: 8401

Re: Fusor progress, Finn Hammer

Richard, Ok, cool. I will try to reduce the value of that resistor, along with the supply voltage to see if it makes any difference. Obviously there is a nasty time constant in there somewhere. I was reading about pulse pile up in one of the publications that Carl Willis pointed out, and there are p...
by Finn Hammer
Mon Nov 20, 2017 8:57 pm
Forum: Images du Jour
Topic: Fusor progress, Finn Hammer
Replies: 25
Views: 8401

Re: Fusor progress, Finn Hammer

Richard,

You are right.

The division is 1mS per div, and the pulses settle in at 500µS

Cheers, Finn Hammer
by Finn Hammer
Mon Nov 20, 2017 8:32 pm
Forum: Images du Jour
Topic: Fusor progress, Finn Hammer
Replies: 25
Views: 8401

Re: Fusor progress, Finn Hammer

First Neutrons!! Noooo, not produced, but measured!, I think. It all started like this: IMG_20171117_145419.jpg And if you can guess what it is, then you are good. It is the first pour of paraffin into a HDPE container made from surplus pipe I found in the Water departments Dumpster. Polyethylene is...
by Finn Hammer
Thu Nov 16, 2017 7:36 am
Forum: Vacuum Technology (& FAQs)
Topic: An interface to the MKS 901P transducer
Replies: 14
Views: 6012

Re: An interface to the MKS 901P transducer

Pablo, The schematic/layout is made in Eagle, and obviously there does not exist proper footprints for the Chinese modules used, this would refer to the Booster/LiPoCharger unit, the max3232 unit, the display, but also the tactile buttons and the on/off switch. Even the footprint of the Arduino modu...
by Finn Hammer
Tue Nov 14, 2017 12:06 pm
Forum: High Voltage - Fusor Input Power (& FAQs)
Topic: Test of Chinese Precipitator Supply
Replies: 8
Views: 3982

Re: Test of Chinese Precipitator Supply

Outstanding work, Finn (as your usual!) Many here will really appreciate your efforts. Thank you for your kind words. Just curious, why not place the supply under oil so it can achieve full potential without arc over? That would be a good solution, as would potting using proper tecnique. While 18 k...
by Finn Hammer
Tue Nov 14, 2017 11:07 am
Forum: High Voltage - Fusor Input Power (& FAQs)
Topic: Test of Chinese Precipitator Supply
Replies: 8
Views: 3982

Test of Chinese Precipitator Supply

All, There has beeen a lot of speculation about the Chinese Precipitator Power Supply's, so with my new power load at hand, I decided to have a go at testing one of said supplies. I work with Precipitators on the side, and to my embarrasment, my boss demanded that we also test these cheap supplies, ...
by Finn Hammer
Sat Nov 11, 2017 2:55 pm
Forum: High Voltage - Fusor Input Power (& FAQs)
Topic: Criticize my HV supply design
Replies: 26
Views: 9403

Re: Criticize my HV supply design

Thanks for your help! This will take some time to digest and I don't think I will be able to do it this weekend as I'm at work. Yes, transformer core selection is a mouthfull. BTW, i cannot seem to find an example of your back of an envelope calculation of the core size, would you mind to publish i...
by Finn Hammer
Sat Nov 11, 2017 10:18 am
Forum: High Voltage - Fusor Input Power (& FAQs)
Topic: Criticize my HV supply design
Replies: 26
Views: 9403

Re: Criticize my HV supply design

Silvio, Litz for 20kHz operation is really easy to make yourself. As you stated, 1mm wire would be fine, so you just bundle enough 1mm wires together and twist them with your power driver. To get access to all separate wires afterwards is also easy: You heat the end of the bundle with a gas torch, u...
by Finn Hammer
Fri Nov 10, 2017 8:31 pm
Forum: High Voltage - Fusor Input Power (& FAQs)
Topic: Criticize my HV supply design
Replies: 26
Views: 9403

Re: Criticize my HV supply design

Silvio, Impressive study of the transformer, but the size of that transformer core and associated windings seem awfully big. 36cm^2 is the size I would expect from an iron core at 50-60Hz, not a ferrite transformer switched at 20kHz. I will have to dig up my copy of Snellings "Soft Ferrites" to subs...