JDC Electronic SA Speedwatch - Manual (Page 8)

8. Technical Specifications
IMPELLER TRANSMISSION
The impellers, fixed on synthetic sapphire
bearings, are equipped with powerful magnets
that generate magnetic impulses. These
impulses are collected by coils (also called
“sensor”) and treated electronically to be
display speed. The magnetic impulses can
go through any materials: fibreglass, carbon
fibre, aramid fibre, wood, plastic, aluminium,
stainless steel, etc. It is why you do not need to
pierce the hull. This system is very sensitive; it
can display a value near an electrical motor or
an electrical light, even if the impeller does not
turn. This is completely normal and does not
affect the reading when the impeller turns.
TRANSMITTER RANGE
The SPEEDWATCH transmitter operates on a
low-frequency (8 kHz) which is wireless display.
Many screens can be used for one transmitter.
The range is ruled to provide the maximum
distance in the watercraft but it cannot create
an interference with other nearby system.
ACCURACY
Tests were made at the Bremen University
(Germany) in hydraulic canals. The results
clearly showed that the SPEEDWATCH is in LDA
(Laser Doppler Anemometry) 3% accuracy.
SPIN OUT
All water tests made in real situatione with high
speed windsurfs (more than 30 knots) showed
that there were no turbulences from the T
attachment which hold the fin. Information
transmitted by major European windsurf
manufacturers.
TRAIL
The impeller trail is 40 grams at 10 knots.
Measurements were made in hydraulic canals
in Bremen University in Germany.
9. Limite Warranty
JDC ELECTRONIC SA extends a 12 months’ warranty over parts and labour for this instrument,
effective from the date of purchase. JDC ELECTRONIC SA reserves the right to repair or replace any
component which may have become faulty in the course of normal use. This repair or replacement
shall be carried out at no charge to the customer (parts or labour). Transport costs however shall
be borne by the customer. This warranty does not cover damages caused by an accident, abnormal
or excessive use, or resulting from an unauthorised modification or repair.
For international warranty support, contact your dealer.
Developed and manufactured by:
JDC ELECTRONIC SA
Avenue des Sports 42, 1400 Yverdon-les-Bains,
Switzerland
Phone: ++41 (24) 445 2121
Fax: ++41 (24) 445 2123
e-mail: [email protected]
Internet: www.jdc.ch