On 09/21/2011 04:57 AM, David C. Partridge wrote:
Howsabout HFC-236fa - very similar properties to R114 but not banned.
Tektronix used a Freon in their 40 KV High Voltage probes. The Vapor
pressure of some of those compounds is low at 70F, but they do have to
be sealed.
I use several of
and frequency measurement
Subject: Re: [time-nuts] Tek high voltage probes
On 09/21/2011 04:57 AM, David C. Partridge wrote:
Howsabout HFC-236fa - very similar properties to R114 but not banned.
Tektronix used a Freon in their 40 KV High Voltage probes. The Vapor
pressure of some of those
For those that reflexively will add that butane is explosive in air:
There isn't any air in the probe if you let the butane boil for a few
seconds, and as long as there is liquid butane in the probe there won't
be any air leaking in.
However, if there is no liquid, you will need to purge out
On 9/22/11 10:34 AM, NeonJohn wrote:
On 09/21/2011 04:57 AM, David C. Partridge wrote:
Howsabout HFC-236fa - very similar properties to R114 but not banned.
Tektronix used a Freon in their 40 KV High Voltage probes. The Vapor
pressure of some of those compounds is low at 70F, but they do
Note that if you change the dielectric in the probe, especially to a
liquid, you may no longer be able to compensate it properly.
The higher dielectric constant will increase the stray capacitances.
Best,
-John
On 9/22/11 10:34 AM, NeonJohn wrote:
On 09/21/2011 04:57
It's going on 10 years now since I last filled a probe. That's the
major advantage of butane. It doesn't diffuse out like the freon did.
On 09/22/2011 01:53 PM, Jose Camara wrote:
John:
One big difference is that when most of the butane leaked out and
air leaked in, you'd get a very
Neither diffuses out. They leak. They could certainly leak at different
rates because of differing MWs, but how tight you made the sealing screw
is likely far more important.
-John
==
It's going on 10 years now since I last filled a probe. That's the
major advantage of butane.
Just a FYI, some claim Ronsonol butane isn't very pure as compared to
other brands. Some lighter manufacturers suggest not to use it in their
devices. I have no idea what trace substances they object to.
Reality? Who knows. Seems most butane comes out of Korea and could
simply be