Video Vbox GPS sensor

[edb49]

I've got a Vbox I've just started using on my car. At the last track day I couldn't get a lock half the time.

I've put the sensor on top of my roll bar - the sensor is magnetic so one of the few places it will stick to. I've then secured it with a bit of duck tape. This obviously isn't working very well for me, so any suggestions/photos of where people have put theirs would be appreciated.

(I thought about bonnet but then you'd have to take it off every time you wanted to get into the engine bay.

[Nicodema]

Hi Ed

Gotta love the look of your R500 (spitting image of our R300)

I've got the RaceTechnology DL1/Video4 setup on ours and it has the same antenna mounting issue. To get the best signal from satellites low in the sky (the ones that give the most accurate data), you need to get the antenna as high as possible so the rollbar is the best spot.

I mount mine on top the bar, where the riser joins from the rear panel of the boot. I run the cable up along with the camera cables, wrapped in black cellophane type loom tape, then tape that to the bar.

On a track day I then wrap the GPS antenna with clear clingfilm style packing tape to make sure it doesn't move. I intend to make a suitable plinth out of body filler over the winter. Maybe I'll make a few or at least post a "how to". I assume you've got the FIA bar with the 'X' bracing.

Martyn

[Walton]

Hi Ed

I run the Vbox GPS on the rollbar without any issues. Make sure the GPS has a good connection into the box, otherwise i'd give Racelogic a bell.

[Nicodema]

BTW, duct tape is superb for blocking the weak satellite signals! Try a single wrap of light coloured insulating tape. Black tape apparently is loaded with carbon (hence the colour) which soaks up the signals and any thick tape like duct tape is worse than a thin one like insulating tape.

Check out RaceTech's how to on mounting GPS antennas

Martyn

[edb49]

Walton said:

Hi Ed

I run the Vbox GPS on the rollbar without any issues. Make sure the GPS has a good connection into the box, otherwise i'd give Racelogic a bell.

Where do you put the recording box out of interest? Mine is attached to the transmission tunnel on the passenger side, I'm just wondering if it is getting interference etc. Maybe I should put it in the boot; disadvantage being I won't be able to see the status whilst driving.

[BertBert]

I held my DL1 GPS receiver to the roll bar using scotchlok (if it's call that). No probs at all.
Bert

[Walton]

Ed

I mount my unit in the boot on velcro, out of the way of feet and prying eyes. If you set the box to automatically start/stop logging at say 20mph, you don't have to worry about logging status!

[Nicodema]

Another vote for the boot, with auto start/stop enabled. I've made a bracket to lift the boxes off the boot floor to avoid them swimming in poor weather. The DL1 is then attached with DualLock (3M industrial velcro)

[David Long]

This is how I did mine. Works OK with no reception problems and keeps things neat under the cover or hood. I've tried both boot and under the dash for the video Vbox but ultimately I like to see the LEDs, so the under the dash works for me.

Edit: From my limited knowledge, it is important and that there is good electrical coupling to the ground plane. Sticking it to a flat surface is important in this respect.

Edited by David Long on Thursday 18th November 13:43

[edb49]

David, I can't quite work out where that is on yours? Is it the main roll bar?

[Nicodema]

Ed, that's by the fuel filler cover, next to the rollbar riser.

David, I'm impressed you're getting no GPS dropouts with that location. Maybe the antenna's a real peach or the steel plate is acting like a really good ground plane. Does your vbox log signal quality? I'd be interested to know how well that holds up as the car rotates round a circuit with all that tubular steel near it.

Martyn

[David Long]

Nicodema said:

Ed, that's by the fuel filler cover, next to the rollbar riser.

David, I'm impressed you're getting no GPS dropouts with that location. Maybe the antenna's a real peach or the steel plate is acting like a really good ground plane. Does your vbox log signal quality? I'd be interested to know how well that holds up as the car rotates round a circuit with all that tubular steel near it.

Martyn

I haven't had any dropouts and usually see (as far as I remember) 5/6 sats or more. I look out some data and post it up. The strange thing was that putting it on the top of the roll bar was not any better. As you say I think this may be related to a ground plane that's working well, rather than a good location.

[edb49]

On the subject of ground planes etc, I have emailed Racelogic about this bit in their manual:

Vbox Lite Manual said:

GPS antennas require a ground plane to operate correctly. This helps to reduce unwanted reflections of the GPS signal caused by nearby objects, and usually the metal roof of a vehicle performs this function. However, if a test requires an antenna to be placed either off the vehicle, or on a vehicle that does not have a metallic roof, you can use an area of metal foil (minimum 15cm X 15cm) underneath the antenna or alternatively a special ground plane antenna must be used. This has an internal ground plane and can operate perfectly without the need for mounting on a metal surface. Ground plane antennas are available from your VBOX distributor (Contact for details).

(Bold is my emphasis.)

[David Long]

Here's a session from Knockhill showing sats from my setup.

[Nicodema]

Hmmm, lightbulb moment! Time to make a groundplane mount for the antenna. I have to say David's looks very tempting for tidyness. I also suspect that running the GPS cable along with the video cables may be a bad plan.

Thanks for the input. Back to the workshop for me.

Martyn