EDS

Eric:

I bought the whole kit from EDS, so I'm assuming I have the correct
regulator. That said, I've never checked the pressure at the first stage
regulator outlet.

Since I've been using a recording oximeter with an audible low sat alarm (a
bit more than $200, unfortunately) for several years now, I'd know if O2
delivery was low. Oxygen is cheap enough that I'm not too concerned about a
bit too much delivery, as long as the bottle lasts the whole of a long
flight.

There are now some OEM Bluetooth-enabled oximeters available from Nonin
that, with some programming, could display saturation and pulse rate on a
PDA screen. The PDA could then provide an alarm. Combined with a cheap
pressure transducer on the bottle, one could monitor all the important
parameters in one place. Something for the WinPilot and SeeU developers to
play with?

I'll contact MH and send the whole kit to them for PM at the next annual.
Meanwhile, I'll check the output of the first stage regulator on the bottle.
With the minor exception of the (slightly) high O2 consumption, I'm very
pleased with the EDS setup. If I were doing it again, I'd buy a bigger
bottle though.

I put a new nine volt into it every two months and recycle the old one into
ground-based, non critical devices; same with the AA cells in the Oximeter.

Thanks for the info.

Ray Warshaw
1LK


----- Original Message -----
From: "Eric Greenwell"
Newsgroups: rec.aviation.soaring
Sent: Wednesday, December 14, 2005 12:51 PM
Subject: MH EDS failures


wrote:
Interesting.... I wonder if the oposite has also happened. I tend to
use a lot more O2 than others using the EDS at similar altitudes; more
than different breathing patterns and/or metabolism would easily
explain.

The EDS depends on the regulator supplying the correct pressure (15 psi).
If the pressure is higher, you will consume more oxygen, and vice versa.
This was the case for a friend of mind (20 psi, I think), and MH replaced
the regulator free. The outlet pressure is easy to measure with any gauge
that can measure 15 psi accurately. I've used a good car tire gauge.

Given that these devices are calibrated by the factory prior
to shipment , and, presumably, could shift, do they ever require
checking and recalibration?

I had this done by MH when I visited their facility. It took only a few
minutes to check the electronic functions and oxygen delivery. I believe
MH will do this for free, if you send your unit to them, but you might
have to pay for the shipping both ways. Contact them - it's been a few
years since I asked.

For those using this device w/out
reference to an oximeter, such checking and recalibration might well be
important.

I agree, but with suitable oximeters costing only $200, there is little
reason to do without one. At least, talk your buddy into buying one so you
can borrow it, or casually mention to his wife that it makes a great
Christmas present! "Deviousness in the pursuit of safety is readily
excused" - author unknown.

--
Change "netto" to "net" to email me directly

Eric Greenwell
Washington State
USA

It occurs to me that, using an oximeter in a feedback loop, the length
and/or pressure of the pulse could be varied by the device to maintain
a target O2 sat. Might need more than a nine-volt to power it though
and the extra stuff would add expense. Add an audible low saturation
alarm and you'd have a neat, albeit more expensive, device.

Ray Warshaw