Just had a look at the manual about repairing the horn and they say you can adjust the tone of it by turning the screw on the back of it.
Bit of a sod as I just splashed out £7 inc P&P for a twin horn set on ebay. Great buy for £7 tho'
Here is the link if your interested
http://cgi.ebay.co.uk/Air-Horn-Set-12V-Dual-Tone-Cars-Trucks-4x4s-Vans-/280588276223?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item41545d51ff
Bit of a sod as I just splashed out £7 inc P&P for a twin horn set on ebay. Great buy for £7 tho'
Here is the link if your interested
http://cgi.ebay.co.uk/Air-Horn-Set-12V-Dual-Tone-Cars-Trucks-4x4s-Vans-/280588276223?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item41545d51ff