Quick summary:
EZ-Trim works a bit like cruise control in a car. It measures pressure height,
compares it to the demanded value (i.e. the value when the "set" button is
pressed
and closes "up" and "down" relays which can be connected to the MAC trim
servo to control elevator movement and thus maintain the demanded height. There
are a couple of buttons to add/subtract 50 feet from the demanded height to
allow fine adjustment.
The unit is controlled by a microprocessor (Basic Stamp variety) and uses a
Motorolla
absolute pressure sensor and a 12 bit analog to digital converter to measure
height. It is relatively simple and could be built by someone with a bit
of experience for around US$100.
I am planning to adapt Cliff's pressure sensor design as part of a more
comprehensive
system I am planning, based on a diifferent processor (Atmel Simmstick)
but this has to complete with Europa building so nothing is going to be
available
in the near future.
Best regards,
Nick
-----Original Message-----
Subject: Re: Digitrak / Digiflight
Hi Jim
I would like to be able to do so and hope to do so in the future! All I
know is that the EZ-Trim is supposed to be able to control a MAC servo
for altitude hold. Go to the site and see for your self. I was not
able to down load the schematics.
Tom
beecho@pw-x.com
-----Original Message-----
From: forum-owner@europaclub.org.uk
Subject: Re: Digitrak / Digiflight
Tom,
Tell us more about the altitude hold using the Mac servo.
Jim Nelson
N15JN
writes:
> Hi Jeremey
>
> Are you aware of the home build EZ-Trim altitude hold device? Cheap
> and
> can control the existing MAC trim to hold altitudes.
>
> Tom
>
> beecho@pw-x.com
>
>
> -----Original Message-----
> From: forum-owner@europaclub.org.uk
> jeremycrdavey@btinternet.com
> Subject: Re: Digitrak / Digiflight
>
> Having heard the recent stories about the quality of some of the
> Navaid
> kit,
> I'm planning on going the DigiFlight 200 route. I can't see a need
> in my
> flying for setting rate of climb/descent, so I'm just planning on
> the
> altitude hold version - if I need to change height it should be a
> simple
> job
> of: hold temporary disconnect button, fly plane manually to new
> altitude,
> release button.
>
> I'm still building wings, though - so nothing is set in stone.
>
> Regards,
> Jeremy
>
> -----Original Message-----
> From: forum-owner@europaclub.org.uk
> Subject: Re: Digitrak / Digiflight
>
>
> Steve.
>
> Yeah, I don't understand why the DigiFlight 100 is so much more
> money
> than
> the DigiTrak. $2575 as compared to $1795, and that's without the
> GPS
> Steering
> feature. I like the fact that the DigiFlight unit is upgradable to
> the
> 200,
> or
> 200VS. Even though those options about double what is already a
> bunch
> of
> money. They're beyond my budget, but I was wondering if anyone else
> had
> selected the DigiFlight route.
>
> Jeff
>
> ScramIt@aol.com wrote:
>
> > I was looking at the EFS one, but I just couldn't get past having
> everything
> > in one box. So I special ordered an EFS lite, Kmd-150, I was going
> to
> order
> > the navaid wing leveler, I helped install one in a Cozy, nice
> unit,
> Then I
> > saw the digitrak and preordered it. I was pushing the budget as it
> was
> so
> I
> > didn't look at much else.
> > SteveD
> > A217
>
> The Europa Forum is supported by Aviators Network UK
> <info@avnet.co.uk>
>
> The Europa Forum is supported by Aviators Network UK
> <info@avnet.co.uk>
>
>
>
>
> The Europa Forum is supported by Aviators Network UK
> <info@avnet.co.uk>
>
>
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