[Prev][Next][Index][Thread]
Re: Victory Neon, Diffusion pumps
On Sun, 19 Nov 1995, Ted Pirsig wrote:
>
> Al,
>
> I've HEARD that the video Vic sells is laughably of the "this is the only
> way to do it" (with lots of, IMHO, *wrong* or purely idiosyncratic
> techniques shown)... cannot say from first hand experience about the
> equipment they sell, other than the electronic choke which was 1) developed
> by Vic based on a Neon News electronic schematic, and 2) not functioning so
> well, according to a friend who bought and returned one.
>
> ----------------------------------------------------------------------------
> ------------------------
>
> Don,
>
> I've used:
>
> 1) Two-stage mechanical pump only, 4 years
>
> 2) Turbomolecular pump, 1 year
>
> 3) Diffusion pump, 3 years
>
> I would no longer operate a shop without a diffusion pump, and even with a
> limitless budget setting up a new shop I would choose a diffusion pump. I
> think turbos are silly overkill with a potential for catastrophic failure;
> I've not seen any of the "scare talk" about backstreaming of diff pump oil
> show up in any real way in the shop; and I agree completely about what
> others have said about "headroom" -- when my mech-only pump had the
> slightest problem-tube then _I_ had a problem.
>
> -Ted Pirsig
>
>
>
Interesting comment Ted... This is really a neat topic. I have been
using one here with a gauge to check the thing and it seems to draw down
real quick. I have used a set up with only a Welch 1402 and a real crude
set up with about a 5kva bombarder and needless to say there were lots of
problems. The combo of not pulling out the impurities fast enough and
not getting the electrodes hot enough were some of them. I think the
"take home" message on this topic is to get a bombarder big enough 15 to
20 kva and a good manifold with a diff pump and you will make nice
bright, log lasting tubes EVERY TIME! You know another interesting topic
to be discussed at some point will be the use of collared vs non-collared
electrodes. I will ONLY use collared electrodes after my experience with
'el-cheapo' ones.
Regards,
Howie Cohen