NSW Appeal for Lost Drivers Licence Due to Damaged Sign?

About 4 months ago I lost my drivers licence after I travelled from what I believed was a 100kmh zone into a 60kph zone where the sign was damaged to the point that it was completely unreadable. Being a truck driver I needed my drivers licence so I appealed the suspension only to find out I could not use the evidence of the damaged sign in a suspension appeal.

Police used a Pro laser 3 to detect my speed. I believed I was doing a speed of about 80 - 90 due to the rough nature of the road. Police captured my speed before dropping out of sight into a DIP in the road. The officer said he used my windscreen as the surface to get the reading.

Question 1. I have looked for what a driver must do in this situation. So far, I have found nothing by way of legislation apart from default speed zones. i.e. unsigned posted areas are 50kph for built-up area or 100kph for default rural speed limit. One would think given the area it would be classed rural 100kph, but it is/was sign posted.

Questions 2. I'm told by a friend police officer from Victoria they can not use the Windscreen to detect speed, is this correct in NSW?

Also, if the officer is tracking my speed while I'm dropping into a dip in the road out of sight, is it possible to get a bad reading if the officers LIDAR beam comes into contact with the ground as I pass into the dip. i.e. a higher speed reading as the distance to the top of the crest is closer to the officer.

Any help with be very helpful.

Thanks.

 

I got photos, and video of the sign. I went to give court a try and have the suspension lifted but no luck. The magistrate said we could not use the photos in that hearing. So stupid, I was told I could not have my licence back as I did not present exceptional circumstances to have the suspension lifted, so I have now waited 5 months to get back into court. Now fighting the fine direct, but I can't find anything on what one should do when a sign is unreadable.