I used Black RTV Silicone to keep the compass from moving during hard landings and wrecks.  I also used 2 header plastics to make sure my compass isn't to close to the IMU.

I spent $42 at Lowes and RadioShack.  It took about 3 hours to build.

                                                    Specs:

                                                22'' motor to motor

                                                4.75'' Tall

                                               360 Grams

Parts List:                                                                     

Qty.           LOWES

1       1/16 thick ( 3/4 x 3/4x 48'')  AL  square tube                                                                          $16.68

1      Aluminum Fire Exstinguisher Sign 4''x16''       $3.96

2      1/16 thick 1/2 x 36'' flat stock                        $5.36

1      50count 5/32 AL rivets                                  $2.90

14    8-32 x 1 1/2 Nylon Machscrews                     $4.50

24    8-32 Nylon Nuts                                            $4.50

                RADIOSHACK

1       6x8'' Prepunched PerFBoard                        $4.00

                                                        Total         $41.90

I used silicon to help dampen Vibrations.                              Fisished Quad Chassi      

 ARM & IMU fit nice and snug.

• Range - 2cm to 3m (~.75" to 10')
• Supply Voltage: 5V +/-10% (Absolute: Minimum 4.5V, Maximum 6V)
• Supply Current: 25 mA typ; 30 mA max
• 3-pin interface (power, ground, signal)
• 20 mA power consumption
• Narrow acceptance angle
• Simple pulse in / pulse out communication
• Indicator LED shows measurement in progress
• Input Trigger - positive TTL pulse, 2 uS min, 5 uS typ.
• Echo Pulse - positive TTL pulse, 115 uS to 18.5 mS
• Echo Hold-off - 350 uS from fall of Trigger pulse
• Burst Frequency - 40 kHz for 200 uS
• Size - 22 mm H x 46 mm W x 16 mm D (0.85 in x 1.8 in x 0.6 in)

Since I have started flying with wireless cameras and recording my flights on the ground hasn't worked out so well.  First I tried recording video straight to my computer with the Diamond VC500 One-Touch video capture device $35 at Fry's, but when I would replay my video's  they were very skippy as well as while trying to fly via the computer screen I noticed that there is a delay in the video witch was causing me to over steer my aircraft making it harder to fly.  So I have found 2 mobile stand alone video recorders that are small, easy to use, and fair priced.  The first unit is Model MVR1020 by Clover electronics us. $70-$180, 1ch Mobile Digital Video Recorder.  Which is what I use.

I like this recorder because it works very well and captures great video.  The only 2 bad things about it are that the software that converts the file to AVI is a flop. The other is  I called Clover and they say that they know about the problem but most of there customers (The Discovery ch) DUB the video to there own recorder or computer.  Witch is what I have done with my Diamond VC500 and it works great.  The second video recorder is MDVR25 at http://www.supercircuits.com/Digital-Video-Recorders/Mobile-DVRs/MDVR25.

I haven't used this divice, but looks ok.?? 

Diamond VC500                                                                              MVR1020

MVR1020 spec. sheet                                                                     

Hope this helps and good luck

This is the Keychain Camera. It's $12 - $25 at Amazon.com and is a great way to record in flight video. It has a 4 gig memory card and 200mha LiPo battery.  The battery will last about 45 mins,  It weights 16 Grams with case and about 11 grams with casing removed.  Takes great pics and video and very crash forgiving.  The newer models now have a sound activated video setting as well.  This camera also works as a USB WebCam.  The time and date stamp I think cam be removed but you might have to use some trickry to do it.  To me this camers works well in bright and dim light conditions. 

Camera: 1280 X 960
Memory: 4 GB internal memory
Time Stamp: Date Hour
Recording: AVI
Resolution (Video): 640 x 480
Frame Rate: 30 FPS
Resolution (Still Image / Photo): 1280 x 960
Indications: LED
Battery Type: 280mAh 3.7V
Connection To PC: USB 2.0
Dimension: 2 x 1 1/4 x 1/2
Weight: 0.7 oz.

This is a still pic of my dog just to show quality is good.