Fixed price repairs are based on the assumption that unit/s received
are ‘original & complete’... a surcharge may be applied to cover
missing parts etc... If in doubt send in the unit for inspection
‘Good luck with your project’... Enjoy your classic motoring...
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check that you are looking @ the latest version... click here
Jaguar XK 120 ( 1948 / 54 )
JDO Instruments
Classic Car Instrument Repairs ( Est 1963 )
Fixed price repairs for most British & European Classic Car Instruments
48hr service available... Why pay more & wait longer ! No UK vat
Tele: 01535 603570 / Mobile: 07872 071512
Please check the FAQ’s page BEFORE ringing / texting / emailing
Connecting diagrams... Smiths & UK Jaeger Rev-Counters
Positive OR Negative Earth*
A= Ignition feed - ve.. (+ ve)*
B= Coil - ve. (+ ve)*
C= Ignition feed - ve (+ ve)*
Case to be earthed + ve ( - ve)*
If unit fails to work REVERSE
A & B connections
These units will not work
with Electronic ignition
upgrade available
(See picture @ top R/H side
For ‘current loop’ info)
Normally Negative Earth*
A= Male bullet Ign +ve
B= Female bullet coil +ve
C= Ignition feed + ve
Case to be earthed -ve
* A few early units were
Positive Earth
These units will not work with Electronic ignition
upgrade available
Negative Earth only
A= Male bullet Coil - ve
B= Ignition feed +ve
( positions may vary )
Case to be earthed -ve
These units will work
with Points OR
Electronic ignition
Some Jaguar units may be fitted with a lead
& a 3 or 4 pin plug
Current loop
( 1 full turn )
Positive OR Negative Earth*
A= Ignition feed -ve (+ ve)*
B= to coil -ve (+ ve)*
Case to be earthed +ve ( -ve)*
( for illumination only )
If unit fails to work REVERSE
A & B connections
These units will not work
with Electronic ignition
upgrade available
(See picture @ top R/H side
For ‘current loop’ info)
Type RVI v1 ‘Universal 80mm unit’
RVI version 1... It is important to retain the nylon block correctly with the metal
clip
& loop the ‘pulse lead’ as shown otherwise the unit will not work
For other Smiths / UK Jaeger instruments
Connections... CLICK HERE