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GRT Mini

Sorry, I guess I'm just as good at estimating time as everyone else around here! Send me your email address and I'll send you a draft of what I have so far. [email protected]

Thanks!
 
Who needs a manual?

NOTE to self: Use teflon tape on all pitot/static connections.
The jumpy readings on VSI are rock steady now that I have added teflon.
 
Yeah, powering up is easy. Just connect 2 wires. It's all the functionality that I'm curious about. :)

How were your pitot/static ports sealed before you added teflon tape? My fittings (from SaifAir) came with a white sealing compound already on them.

Thanks,
Russ
 
Dry, white plastic B nuts, ferrules and tubing from my engine shop. Felt tight to me but apparently we're not. Very gentle wrench torque this time as well
Advanced features easy to work with. Just pwr up and play around. Engine noises optional while sitting still. Great product!!
 
Thread sealant

flightlogic said:
NOTE to self: Use teflon tape on all pitot/static connections.
The jumpy readings on VSI are rock steady now that I have added teflon.
Click to expand...

Good point-- I added that to the manual. Loctite 567 thread sealant paste has been used in a lot of GRT EFIS installations with success. (Standard procedure at the Jabiru S-LSA factory.) Loctite 565 would also work. Just make sure you go easy on the tape/sealant so the ports stay clear!
 
UPDATE: Mini-X Shipping, Mini-B Manual now available

I'm pleased to announce that we've started shipping Mini-X units this past week! Production is still slow, but improving as our engineers are finishing up the test fixtures necessary to transfer the testing duties to our regular production staff. Again, we apologize for the delays we've had, but we're confident your Mini will be worth the wait.

On a related note, the Mini-B Installation, Setup & User Manual is now on our website. We are still finalizing the details of the backup battery, so that is absent for now but will be included in an upcoming revision. The Mini-X manual has more information about the map, HSI, synthetic vision, autopilot controls, and magnetometer, and will be released in the coming days.

For those installing a Mini-X with magnetometer-- The main difference between the Mini-X magnetometer and all of our other magnetometers is that you can mount it on its side or tilted in relation to the AHRS (display unit case)-- the only limitation is that it cannot be more than 60 degrees pitch-up or pitch-down in relation to the FORWARD arrow. This will make installation much easier. In many cases, no bracket will be required-- in Greg's own words, "you can just stick it to a wing rib." The magnetometer is the same size & shape as our original one. If you're planning out the location of your magnetometer, follow the instructions in the original magnetometer installation notes (found here: http://grtavionics.com/mag_D.pdf) with the exception that orientation is not as critical.

We have a new software version currently in beta testing for those of you who got early versions of the Mini-B, so if you see features in the manual that you don't have right now, you'll probably have them next week.

That's all for now, have a great Memorial Day weekend! :cool:
 
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Erik. Good coincidence. It is a really nicely engineered, bright screen EFIS.
I remember half way through production run of G396, they got way brighter. Display technology has advanced so much. You are never going to miss the old pump!!!
 
Rev A para 2.3 (p14) says it's desirable to have the Mini powered off during engine start in order to increase the life of the backlight.

Does including a backup battery help at all with this?

Edit: along the installation lines, what is the footprint of the external GPS antenna?

Thanks for your time!
 
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Irgabriel - a few words of explanation... In that paragraph you cited you'll see a reference to the backlight being a CCFL, or a Cold Cathode Flourescent backlight. These backlights have a lifespan which is dependent on the number of start-up cycles they receive. As such it is advisable to not subject them to multiple turn-on cycles associated with starting the engine (imagine you don't get the engine started the first time, so you crank again... and maybe a third or fourth time... that really adds start-up cycles on the backlight).

Installing a backup battery which provides power during an engine start "brown out" condition is a good idea so you can keep your EFIS and engine monitor alive during engine start.

With respect to the Mini, I'm not sure that it is still using a CCFL backlight and may have migrated to LED backlighting (the wording in the installation manual may be a direct cut and paste from the HS/HX manual). If the Mini is using LED backlighting then you are less likely to see a reduction in backlight lifespan as a result of power cycling during engine starts. Irrespective of this consideration, having the EFIS and engine monitor powered by a backup battery will allow you to monitor the engine more closely and will allow your EFIS to align more quickly.

In our installation the Horizon HS EFIS has one of its power inputs tied to the main buss and one tied to the essential buss - whichever bus has the higher voltage is the one which powers the HS. The Mini is powered directly from the essential buss. The essential buss is powered by its own battery and that battery is charged from the main buss through an isolation diode. This architecture provides a simple means of achieving brown-out protection and redundant power sources for the EFIS devices.

The footprint of the GPS antenna is quite small, about 1.5" x 1.5". It's surprisingly heavy for its size!
 
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I'm predominantly wondering if the caution against having the Mini powered during engine start is related to 1. Overall low voltage on the bus, or 2. Unstable voltage on the bus.

CCFL backlights use intricate inverter/voltage regulation schemes, and I didn't know if the caution was related to low voltage--easily cured by using GRT's backup battery--or if it was related to noise, which isn't so easy to isolate.

I have two completely independent electrical systems. The only time they're anywhere near each other is when the starter contacts close and connect both batteries to the starter. As a result, I'm hoping the Mini's backup battery will solve its sensitivity to engine starts--I don't have a bus that's isolated from them, and I don't want to add a switch for a single device.

Thanks for the note about the GPS antenna--I have exactly a 2" square I was hoping it would fit in.
 
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Mini-X Installed

I just installed my Mini X. I have the autopilot function as well. It was purchased as a back up for my Sport SX in the event of an inflight failure. It has a great screen, is easy to read and works the autopilot servos as described. It is actually brighter than my Sport SX. I had an issue with the autopilot function but it was my on fault with my source selector switch.

I am very pleased and everyone that has seen it loves it. I do have a back up battery that I wired thru a Diode that provides 12v at all times during a start or emergency operation.

Thanks to Ben at GRT for all the technical support, I've called him enough he knows my number :cool:
 
Vag277 said:
Katie

Does the Mini B come with a nav (GPS) data base that covers Australia?

Kim
Click to expand...

For airports, navaids, and man-made obstacles: The only free nav database we are able to provide is the U.S. database. All other locations will need a Jeppesen subscription database, downloadable here. Note that the Jepp page says HX/SX but the Mini uses the same data package.

If you already have a GRT EFIS screen with a Jepp subscription, you can load the single subscription database into each GRT EFIS in the plane. So if you add a Mini to your GRT system, it won't cost you more subscription fees.

For Synthetic Vision (Mini-X, Mini-AP): If you specify at the time of purchase that it's going to fly in a different part of the world than North America, we'll load the SV terrain data for your continent here at GRT before it ships. That does not cost anything extra, but it is too much data to host on our website, so we need to load it here.

About the backlight-- Great questions. I'll ask the engineers for some more detailed info.
 
Mini software

Hi All,

We've just published the first revision to the Mini software. Minis recently shipped will likely have all 3 updated, but check yours to make sure.
Check your software versions by observing the boot-up screen (before pressing ACCEPT on startup.) All 3 software versions and the navigation database date will be displayed on that screen.

The Mini is unique to other GRT EFIS systems in that one software package applies to all Mini models. Your unit will automatically detect and load the portion of the software package that it requires.

AHRS software is loaded differently than the regular GRT EFIS in that it is a single-step process. (Set Menu > AHRS Maintenance > Load AHRS Software).

Air Data (Pitot Block) software is probably going to be a rare update, but you might see some changes to this early on as Minis gain more fleet hours. Ensure you have Version 3.

Complete instructions for updating your Mini (all models) can be found in the Appendix of the Mini-B Installation, Setup and User Manual.

Also, there's a new Navigation database update available as well. Make it an update party! ;)
 
lrgabriel said:
I have two completely independent electrical systems. The only time they're anywhere near each other is when the starter contacts close and connect both batteries to the starter. As a result, I'm hoping the Mini's backup battery will solve its sensitivity to engine starts--I don't have a bus that's isolated from them, and I don't want to add a switch for a single device.
Click to expand...

The CCFL backlight does not apply to the Mini-- it's all LED. So, that sentence of the manual will be revised. Todd said the Mini is built to take voltage spikes related to engine start, but it's best practice to keep it separated from the starter circuit. (Why stress it if you don't have to, is the thinking here.) A backup battery will protect it against voltage drops which can cause it to reboot during engine start.
 
n38139 said:
I just installed my Mini X. I have the autopilot function as well. It was purchased as a back up for my Sport SX in the event of an inflight failure. It has a great screen, is easy to read and works the autopilot servos as described. It is actually brighter than my Sport SX. I had an issue with the autopilot function but it was my on fault with my source selector switch.

I am very pleased and everyone that has seen it loves it. I do have a back up battery that I wired thru a Diode that provides 12v at all times during a start or emergency operation.

Thanks to Ben at GRT for all the technical support, I've called him enough he knows my number :cool:
Click to expand...

Steve-- thanks for the review. Glad you like it!! :D
 
Katie -

Thanks for looking into this, and for the amazingly rapid answer. You guys rock!

I'll get some data back to this thread after I can get a scope on the bus and put it through a few engine starts...just to be sure nothing overly sinister is reaching the Mini. I'm not expecting a huge voltage drop (due to having double the normal battery capacity during start), and I'm using high quality, diode-protected contactors...so we'll see.

Anyway, thanks again.
 
Any others get their mini X yet ? I know I'm close but it's harder to wait at the end. :)

This question will vary a lot DOE but how long are you guys taking to install this thing ?
 
It depends, as you say ...

erikpmort said:
Any others get their mini X yet ? I know I'm close but it's harder to wait at the end. :)

This question will vary a lot DOE but how long are you guys taking to install this thing ?
Click to expand...

It can be done in a day or less than an hour ... depends.

If you want to get it done the fastest, consider checking to see of you can get the harness for the magnetometer early. Then run that wiring and make the mounting mechanism for the box. The box is the same "standard little box" that GRT uses for a lot of stuff, BUT the connector on the Mini Mag is different (reverse sex of the standard magnetometer.)
<<This work is the largest time consumer.>>

Then if your plane is not flying already cut the hole in the panel and mount #4 (yes number FOUR) plate nuts. Suggest hex head socket screws.
<<This is probably second longest, unless you get someone like Stein to cut your panel in advance. :) >>

If you don't have any and need them in a pinch, ACE Hardware probably has some (black anodized).

Make available power and ground wires for connection when device received.
<<Probably already available.>>

Make available a "T" for Pitot and Static.

If/when the above is done, it can easily be done in about 30 minutes.

If not, it *can* take a day. Interruptions, breaks for lunch, head scratching, putting plane back together etc. :)

Interdisplay, autopilot etc connections and setup will add to the time.
 
It would be most helpful if those who have successfully sourced the necessary #4 nutplates to share their sources and part numbers. When I tried Spruce the only ones they had were p/n 04-02028 (F2000-4) floating anchor nut. These are too big for the job as the floating base of the nutplate is too large. I've since fabricated my own fasteners thanks to having a 4-40 tap on hand.
 
One other source for nut plates

Canadian_JOY said:
It would be most helpful if those who have successfully sourced the necessary #4 nutplates to share their sources and part numbers. When I tried Spruce the only ones they had were p/n 04-02028 (F2000-4) floating anchor nut. These are too big for the job as the floating base of the nutplate is too large. I've since fabricated my own fasteners thanks to having a 4-40 tap on hand.
Click to expand...

Cleveland Tool

Cleveland Tool
Their part number GMS21047L04
 
I just picked up some myself from another source of hard to find hardware: B & B Aircraft Supplies. 33 cents a pop.

These guys are always at Oshkosh in the Fly Market outside vendor area. Great booth to visit to pick up some interesting parts!
 
I ordered mine, a Mini X, at S&F. It has not arrived yet but I have already installed the wiring harnesses for the unit and the magnetometer as well as the GPS. The mounting hole is cut and covered with a blank so installation will be less than an hour when I get it. It is going on the right side of my panel to augment the dual HX's in my flying RV7A so I have something to look at when my wife is PIC. To bad it is not here yet since we leave for a one month flying trip this weekend!

Martin Sutter
Building and Flying RV's since 1988
 
Tech question

Regarding the Mini X, is there any difference in the current draw when connected to the magnetometer vs not using the magnetometer?

Thanks in advance.
 
F1R said:
Regarding the Mini X, is there any difference in the current draw when connected to the magnetometer vs not using the magnetometer?

Thanks in advance.
Click to expand...

Yes, but it's tiny. The current draw from the magnetometer is around 50 milliamps, so it's not an appreciable difference.
 
I wonder, what are chances that a version of Mini would ever be certified under TSO C145/146 or C196? Combined with Trig TT22, which is certified under C166b, this would create a somewhat inexpensive ADS-B solution (under $3800 total). As I understand the situation, Mini already uses a 5Hz WAAS GPS, so precision requirements are met. It only needs to satisfy reliability requirements.
 
zaitcev said:
I wonder, what are chances that a version of Mini would ever be certified under TSO C145/146 or C196? Combined with Trig TT22, which is certified under C166b, this would create a somewhat inexpensive ADS-B solution (under $3800 total). As I understand the situation, Mini already uses a 5Hz WAAS GPS, so precision requirements are met. It only needs to satisfy reliability requirements.
Click to expand...

The problem with certification is that the cost of the extra labor and bigger facilities and computer programs required for intense inventory control and production processes, along with all the documentation, would kick the price of the Mini up to the same range as all the current TSO'd displays. Even if the hardware meets the requirements, the extra overhead cost of certification is what you'd pay for. For now, at least, we prefer to stay a manageable size and keep our prices down.

Not to say the ADS-B requirements won't force an economical solution. I'm confident there will be, but it will likely come from bigger companies already established in the certified world.
 
Magnetic Base

Can the magnet be removed from the GPS ant. base for the mini? Or can a new GPS ant. be purchased with no magnet in it?

The Mini X is an awesome package overall.
 
F1R said:
Can the magnet be removed from the GPS ant. base for the mini? Or can a new GPS ant. be purchased with no magnet in it?

The Mini X is an awesome package overall.
Click to expand...

Yes to both-- You can remove the magnets by peeling up the backing label and removing the screws that hold the magnets in. (Put the screws back in so the whole thing doesn't come apart, though.) You can also find non-magnetic MCX GPS antennas online. Magnetic ones are the most common because people usually stick them to the roof of their car.

I will add this to the manual as a note for those with a Mini-B or Mini-X without the remote magnetometer. No use introducing useless magnetic interference if the GPS antenna is on the glare shield.

Glad you like it! :D

UPDATE: I've just been informed that our next batch of GPS antennas will be non-magnetic because it will be best for the Mini-B.

IMG_20140626_152754780.jpg
 
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If we prefer to use a magnetic mount, how far from the magnetic antenna is safe for the Mini-B's internal magnetometer?

I have a thin steel plate on my glare shield to magnetically mount my GPS antennas.

Thanks!
Russ
 
grayforge said:
If we prefer to use a magnetic mount, how far from the magnetic antenna is safe for the Mini-B's internal magnetometer?

I have a thin steel plate on my glare shield to magnetically mount my GPS antennas.

Thanks!
Russ
Click to expand...

Hi Russ, sorry I missed this question when you posted it.

Our programmer said any magnet or ferrous steel within a couple of feet is "not the best situation," but it really won't affect the Mini-B significantly because its main source of directional data is the GPS track.
 
Mini Shipping Update

I thought I'd post an update for Mini production rates. On average, we're completing & shipping 3-5 units per day. Oshkosh will interrupt Mini production and shipping for about a week, since much of our crew will be there to help man the booth.

If you get a message from Jon that your Mini is ready to ship, please get back to him as soon as you can to confirm. If you get a call but aren't ready to receive it yet, that's OK-- let us know and we can shuffle your ship date down a couple weeks and send it to someone else who's waiting.

Thanks & see you at OSH!
 
Katie - one suggestion for an update to the Mini installation manual. It seems the interface to the Trig T22 transponder is missing a critical piece of information that will no doubt cause Mini installers problems.

To get the TT22 to turn on, you must ground its "Power On" input (Pin 13 on the TT22). The TC20 dedicated control head grounds this line to turn on the transponder. Since the Mini doesn't have a discrete output to control the TT22, one must either hard-wire Pin 13 to ground, or install a switch to switch ground onto that pin. Grounding Pin 13 turns on the TT22 transponder.

This info needs to go into the Mini installation manual.
 
Canadian_JOY said:
Katie - one suggestion for an update to the Mini installation manual.
To get the TT22 to turn on, you must ground its "Power On" input (Pin 13 on the TT22).
This info needs to go into the Mini installation manual.
Click to expand...

She's already on it... :)

-Dj
 
Canadian_JOY said:
To get the TT22 to turn on, you must ground its "Power On" input (Pin 13 on the TT22). The TC20 dedicated control head grounds this line to turn on the transponder. Since the Mini doesn't have a discrete output to control the TT22, one must either hard-wire Pin 13 to ground, or install a switch to switch ground onto that pin. Grounding Pin 13 turns on the TT22 transponder.
Click to expand...


Yep, I'm on it! (Dj told me about this a couple days ago.)

I just uploaded the revised Mini-B and Mini-X manuals to the website. You might have to refresh your documentation page to get it. Section 2.5 is now expanded to include information about the ground I didn't know about. We're recommending just wiring it to ground for simplicity. If you want an external transponder switch, you can do it that way as well, but that adds complexity when you could just have a pullable breaker to shut down the transponder separately from the avionics switch.

I've also included the option to use a Dual Control Adapter and wire the Trig to both your primary GRT EFIS (Sport SX or Horizon HX/HXr) and the Mini. We recommend just using the Mini since it's half the wiring and you don't need a serial adapter-- but some might want to do it this way.
 
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GPS puck

Ok to put my GPS puck on the glare shield ? The manual says no to under the cowl though many seem ok with that.

My compass is mounted to my center bar on the glare shield though. Maybe if i put it in one of the corners I'll be far enough away from it.

Really looking forward to lighting this thing up ! Thanks to grt team
 
Sure, anywhere within view of the sky is fine for the GPS antenna. If you put it next to the compass, you can remove the magnets from the puck. It will work fine under a fiberglass cowl as long as it doesn't melt.
 
New AHRS software for Mini-X

Hi All,

We've posted an update for the Mini-X AHRS software that fixes the bug in the remote magnetometer calibration. Please update your AHRS software to version 50 using the AHRS software update instructions in the back of the Mini-X manual, then run through the magnetometer calibration procedure and you'll be all set.

As always, we recommend thoroughly testing new software in your system in VFR conditions first. So if the Mini is working fine without the remote magnetometer and you plan to fly IFR in the next few days (such as flying to OSH), you should probably wait to do the update until you get back. (This is for the Mini-X only-- the calibration bug did not pertain to any of our other EFIS systems.)
 
Almost finished with install. It was a great experience to learn more about the systems in my plane and the hardware package and instructions were good. If you get the wrong plug for the magnetometer they'll get one to you in the mail quickly. The efis looks awesome and I think it will exceed my expectations. A couple quick questions-

Will the efis only display airspeed in knots ? I was trying to find an option for that in the system menu. That will be a bit of an adjustment if so because my airspeed indicator was in mph.

I removed most of my vacuum system except the pump itself on the back of the motor. I think I may need to wait till my next oil change because I may have to remove the oil filter to access one of the pump screws.

So is there any problem with leaving the two hose lines open on the pump ? Or should the holes be capped off ?

When I grounded the oat the true airspeed icon popped up, but is it supposed to show the actual oat on the screen somewhere ?

Should get my first flight behind it Monday.
 
erikpmort said:
I removed most of my vacuum system except the pump itself on the back of the motor. I think I may need to wait till my next oil change because I may have to remove the oil filter to access one of the pump screws.
Click to expand...

I ran into this. My friendly neighborhood A&P dropped by, took a long flat bladed screwdriver and a hammer, and whacked the nut at an angle against the side of a flat on the nut to loosen it, then we just used fingers to remove it.

You will need a flat plate to put back on the engine to cover the hole that the pump leaves.

-Dj
 
Thanks dj that sounds doable. Did you just make a plate ? I have some alum left over from my new instrument panel so I guess I can use that and reuse the gasket. That is the last thing I have to do !
 
I bought a cover plate from Robert Paisley (http://www.flyefii.com/ - I think it was about $20 with shipping) and a new gasket from Aircraft Spruce for a couple of bucks.

I would not recommend re-using the gasket. Mine ended up in pieces in the removal process.

-Dj
 
erikpmort said:
I have some alum left over from my new instrument panel
Click to expand...

I just looked for a picture but couldn't find one. The new cover plate is pretty thick, like 1/4 of an inch or so. I'm not sure the instrument panel material would be adequate, and I'd not want to find out while in flight... :)

-Dj
 
erikpmort said:
Will the efis only display airspeed in knots ? I was trying to find an option for that in the system menu. That will be a bit of an adjustment if so because my airspeed indicator was in mph.
Click to expand...

Go to Set Menu > General Setup, and you should be able to select between kts and mph under the speed and distance units.

http://www.grtavionics.com/Mini-X A2.pdf Page 25.

I have about 6.5 hours on my Mini-X and HX now (converted from an old analog panel like you are doing). It is a pretty big change to go from the analog airspeed indicator to the digital speed tape. I am getting there, and I am still "Chasing the numbers" a bit when on final approach, but I think this is having a positive effect of keeping the airspeed more controlled versus the analog gauge where it is harder to tell a couple of knots difference. It is getting easier with practice, but it was definitely a surprise on first flight. :)

-Dj
 
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