Search found 15 matches

by Peter Schmelcher
Fri May 14, 2021 1:27 pm
Forum: The water cooler -- disscusions about anything
Topic: Life, The Universe, and Everything
Replies: 340
Views: 6368098

Re: Life, The Universe, and Everything

My condolences to Bill and Doug’s friends. He was one of a kind and is missed.

I got to know Doug over many years via google video hangouts.

Often, he would quote a line from ‘The Hitchers Guide to the Galaxy’ and I would respond with some another.
Doug, Thanks for all the fish.
by Peter Schmelcher
Thu Feb 09, 2017 11:38 pm
Forum: Vacuum Technique
Topic: Turbos and intermittent backing
Replies: 9
Views: 22037

Re: Turbos and intermittent backing

Jerry ion pumps have a steep the learning curve. Mine is a triode vacdiode and oddly increased the chamber pressure when ever it was powered on. The trick or rather necessity is a good high temperature bake out. The collector plates are a sponge and when exposed to atmosphere they saturate with ...
by Peter Schmelcher
Sat Feb 04, 2017 3:22 pm
Forum: High Voltage, High Power
Topic: Doug's latest feedthrough work
Replies: 10
Views: 24903

Re: Doug's latest feedthrough work

Doug Loctite 770 is surface prep for use with Loctite 440 instant glue. The stuff is good for gluing rubber and Teflon. I believe it cuts surface bonds to chemically attach to. Might be worth a test with BN and an o-ring.
-Peter
by Peter Schmelcher
Sat Feb 04, 2017 2:49 pm
Forum: Vacuum Technique
Topic: Turbos and intermittent backing
Replies: 9
Views: 22037

Re: Turbos and intermittent backing

Bob my setup has a turbo drag and a 4 stage diaphragm roughing pump but running next to you the constant noise gets old fast.

You should consider an ion pump. I have a used 20 l/s Varian which runs at 3300V and the current is an indication of the pressure (100uA is 0.9E-6T). Mine runs continuously ...
by Peter Schmelcher
Mon Jun 01, 2015 4:29 am
Forum: High Voltage, High Power
Topic: Need up to 10kv at up to an amp.
Replies: 15
Views: 33480

Re: Need up to 10kv at up to an amp.

Jerry I’d be shocked if you couldn't configure a motor VFD to drive a step up transformer, both are just steel and copper with the same physics. 30 years ago in university we modeled induction motors as transformers.
Enjoy the journey.
-Peter
by Peter Schmelcher
Sat May 30, 2015 7:26 pm
Forum: High Voltage, High Power
Topic: Need up to 10kv at up to an amp.
Replies: 15
Views: 33480

Re: Need up to 10kv at up to an amp.

Jerry,
I am guessing you want a metallic coating so voltage regulation is not that big a deal. How about a rectified pole transformer driven by a variable frequency AC drive?
-Peter
by Peter Schmelcher
Tue Feb 03, 2015 11:34 pm
Forum: inorganic chemistry
Topic: PEM Fuel Cell
Replies: 3
Views: 20069

Re: PEM Fuel Cell

I looked at all the usual suspects for drying awhile back. Some might be fine but probably not great and I did not want to invest in an RGA to know the answer. I liked zeolite as the drying medium and I eventually found a few commercial drying products with specifications that used it.

Zeolites ...
by Peter Schmelcher
Thu Jan 29, 2015 8:49 pm
Forum: inorganic chemistry
Topic: PEM Fuel Cell
Replies: 3
Views: 20069

PEM Fuel Cell

Almost two years ago I did some experiments with a Proton Exchange Membrane or PEM fuel cell. Only a few companies actually make these membranes. This fuel cell came out of a science toy called a Hydrocar. The highest current I ran the cell at was 4.5 Amps while producing 36 sccm of hydrogen gas. In ...
by Peter Schmelcher
Thu Jan 22, 2015 2:10 pm
Forum: Formulas and data constants
Topic: Decay table
Replies: 0
Views: 9310

Decay table

I came across this decay table via the Geiger enthusiast group at yahoo. As best I can figure it was intended for use with the GR-130.
-Peter
by Peter Schmelcher
Sat Nov 08, 2014 1:39 pm
Forum: Metrology
Topic: Photographing fusors and near IR issues
Replies: 8
Views: 21521

Re: Photographing fusors and near IR issues

I used a poor choice for an angular description. The #64-463 hot mirror has a dielectric coating thickness designed for operation at 45 degree. http://www.edmundoptics.com/optics/optical-mirrors/specialty-mirrors/high-performance-hot-mirrors/3150
As the 45 degree angle is changed the photon travels ...