K80RUM

A Caterham Superlight-R
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Bulletcams
Autocom Intercom
Corner Weighting
New Dashboard Switchgear
Emerald ECU Install
Emerald upgrade to K3
PRRT
FreeStyle Inboard suspension
Freestyle Diffuser
Wider Rear Wheels & Wings
Lowered Floor
AIM MXL dash display
Aeroscreen
Sound & Vision recording
 
I'm finally getting around to kitting out the car with sound and vision.
 
Two bulletcams will eventually be used - at the moment I only have one. The idea is to have one fixed on a rollbar clamp and the other moveable using a dogcamsport suction mount. The suction mount allows me to get shots from anywhere on the bodywork or from a helmet.
 
                                     
 
 
 
Two bulletcams are Sony VB21HQ-R43s from RFConcepts, using an 8mm and a 4.3mm lens. These high-quality cameras have a low-light capability and a high recording resolution of 550 Lines. The third is a Sony 520TVL recording at 520 lines. The 12v cameras are powered by the main car battery their outputs feed the camcorder via a feed-selector switch on the dashboard. There wasn't anything commercially available and suited to this application which would switch more than 2 bulletcams, so I'm building something myself. A 3-pole, 4 way rotary break-before-make switch will be mounted in the dashboard with a selector knob. This switch will cycle through the 3 bulletcam video-output signals and transfer the selected one to the camcorder. This should allow on-the-fly camera switchng while the camcorder's recording.
 

 
The recorder is a Sony DCR-PC120BT mini-DV camcorder running in VCR mode. Perhaps in the future, a solid-state recorder could be used but they're expensive and the camcorder will do a good job for nothing. The cameras feed the camcorder via a 3.5mm video-in jack. The 8.4V camcorder is powered from the 12v car battery through a Sony voltage convertor - the Sony DCCL50B. It took a bit of time to find this but was worth it, since it converts perfectly from a 12v cigarette lighter, to the odd camcorder 8.4v power socket. 
 
Finally, in order to simply and safely stop/start the VCR recording, a dogcamsport LANC connector is used. a simple push button on the dashboard stops and starts the recording. An integrated LED even warns when the tape level is low.
 
          
 
The standard bulletcam microphones are not up to the job of delivering serious sound. Instead, a SessionMaster percussion microphone, specifically tailored for bass work is being used. Eventually twin microphones will be used - one on the exhaust side of the rollcage and one on the induction side of the engine compartment. These microphones are fed to a preamplifier in the boot which acts as a focal point for the microphone and camera data. It also supplies power to everything. The camcorder sits in a padded box alongside it in the boot.
 
Bulletcam Setup
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I've taken some test footage. It's rubbish for 3 reasons -
i) The camera mount moved slightly before I set off, so the shot throughout the drive is less than ideal
ii) The external microphone is no good at providing sound. It's now been mounted next to the airbox in the engine bay and picks up the induction bark - much better!
iii) For some reason, stupid OfficeLive is refusing to allow me to upload the original .WMV file, despite it being within their size limits. I've downconverted it to be smaller, but the result is worse quality.
 
Anyway, you can watch the first run here
 
Here's the first mic test after moving to the engine bay. here