A roamer is a simple device for plotting easily onto maps. Buy one and attach it to a loop of string around your neck so that you don't misplace it.
https://www.donbarrow.co.uk/1%2750,000_r...omers.html
An average speed chart helps you keep to time. As an example the regs may say travel at 18mph between time control one and time control 2. The average speed chart is calibrated to your speedo/odometer and tells you how many minutes/seconds should have elaspsed to cover increments of miles, allowing you to keep at the required average. You simply can't do the maths in your head on the hoof! It requires you to zero the odometer on leaving a time control and reset your stop watch. If you don't have an odometer you need to note the mileage reading.
To make one you need to do a measured loop in your modern. About 5-10 miles is good. Note the mileage, assuming that your modern has an accurate speedometer. Then do exactly the same loop in your old car and note the mileage. From this you know how inaccurate your old car speedo actually is. It's then a simple matter of Excel to work out charts showing the elapsed time for 0.5 mile distances . Print and laminate the chart showing 0.5 miles to 10 in the top row and elapsed time in the row below. Repeat for average speeds of 16, 18, 20, 22 and 24 miles per hour. Check what the regs say; they usually warn you.
I humbly disagree with Mike about the need for a poti. With modern led headlamps and a cheap magnifying glass you can live without one. Poti's are something else bulky in between the navigators feet!
Does that make sense?
If you message me with your email I'll send you a scan of a very useful guide
Best wishes
Charles
BTW I did once lose middle of the three OS maps halfway round a Measham.
We guessed the route from an AA road atlas and worked out where we probably needed to renter the final map.
We weren't last!
Charles
https://www.donbarrow.co.uk/1%2750,000_r...omers.html
An average speed chart helps you keep to time. As an example the regs may say travel at 18mph between time control one and time control 2. The average speed chart is calibrated to your speedo/odometer and tells you how many minutes/seconds should have elaspsed to cover increments of miles, allowing you to keep at the required average. You simply can't do the maths in your head on the hoof! It requires you to zero the odometer on leaving a time control and reset your stop watch. If you don't have an odometer you need to note the mileage reading.
To make one you need to do a measured loop in your modern. About 5-10 miles is good. Note the mileage, assuming that your modern has an accurate speedometer. Then do exactly the same loop in your old car and note the mileage. From this you know how inaccurate your old car speedo actually is. It's then a simple matter of Excel to work out charts showing the elapsed time for 0.5 mile distances . Print and laminate the chart showing 0.5 miles to 10 in the top row and elapsed time in the row below. Repeat for average speeds of 16, 18, 20, 22 and 24 miles per hour. Check what the regs say; they usually warn you.
I humbly disagree with Mike about the need for a poti. With modern led headlamps and a cheap magnifying glass you can live without one. Poti's are something else bulky in between the navigators feet!
Does that make sense?
If you message me with your email I'll send you a scan of a very useful guide
Best wishes
Charles
BTW I did once lose middle of the three OS maps halfway round a Measham.
We guessed the route from an AA road atlas and worked out where we probably needed to renter the final map.
We weren't last!
Charles