Have I missed something here ......
Today I was going to fit a new Dizzy pick-up and base plate unit ( Rimmer part No. RTC 5090P1 ) this is OEM unit NOT the "Britpart" cheapest or the Original very expensive unit either, a middle range job? At £80+ it should be a decent replacement.
Before I begun to fit this unit I checked the pick-up for a resistance test using a very good multimeter, the one in the car reads 3K2 Ohms (3200 Ohms) and it will help produce a spark though it is playing up. I have tested my amp and that is perfect. My amp is a £25 - £30 job from a motor factor and has worked well for at least 5 years with the 35DML8 dizzy.
The resistance test on this new unit produced a Zero reading so I tried a continuity test and that also produced a Zero reading.
The pick-up itself is just a coil surrounded by a magnet, therefore the coil sits in the middle of a permanent magnetic field. Disturb that magnetic field with metal very close to - or touching the coil with it - and a very small AC voltage is produced. A very, very basic principle .... but it works
Would you the reader think as I do the pick-up coil is useless? No continuity and no resistance either through the winding.
What, if anything have I missed?
Many thanks ....Mike
Ign. Pick-up
Moderator: phpBB2 - Administrators
Re: Ign. Pick-up
How can it have neither continuity or resistance? That's like saying it's a perfect conductor and a perfect insulator.
Re: Ign. Pick-up
According to my SD1 BL manual, the correct resistance for the VR sensor in a DLM dizzy is 950-1150 ohms.
Dave
London SW
Rover SD1 VDP EFI
MegaSquirt2 V3
EDIS8
Tech Edge 2Y
London SW
Rover SD1 VDP EFI
MegaSquirt2 V3
EDIS8
Tech Edge 2Y
-
- Forum Contributor
- Posts: 208
- Joined: Thu Mar 25, 2010 8:49 pm
- Location: Markfield, Leicestershire.
Re: Ign. Pick-up
Thank you Gentlemen for your replies.
GDCobra ... I am talking about a coil of wire - the pick-uo - if it hasn`t got continuity the resistance must be infinity, i.e. open circuit.
Dave, Thanks for those readings a useful point to remember. I checked my multimeter on the Ohms reading with a 4700 4K7 Ohm resistor ( yellow, violet, red ) and it read true as I didn`t believe the 3K2 reading.
The reading I get from my fitted Pick-up ( disconnected from the amp ) of 3K2 Ohms explains why my pick-up coil is playing up. The amplifier is easily tested and produces a very good output at the coil - I have seen the king lead spark 40mm and felt the bugger as well.
The pick-up coil without continuity is obviously US - I just wanted to know I hadn`t missed something.= it can now be returned as faulty.
Thank you both, Mike
GDCobra ... I am talking about a coil of wire - the pick-uo - if it hasn`t got continuity the resistance must be infinity, i.e. open circuit.
Dave, Thanks for those readings a useful point to remember. I checked my multimeter on the Ohms reading with a 4700 4K7 Ohm resistor ( yellow, violet, red ) and it read true as I didn`t believe the 3K2 reading.
The reading I get from my fitted Pick-up ( disconnected from the amp ) of 3K2 Ohms explains why my pick-up coil is playing up. The amplifier is easily tested and produces a very good output at the coil - I have seen the king lead spark 40mm and felt the bugger as well.
The pick-up coil without continuity is obviously US - I just wanted to know I hadn`t missed something.= it can now be returned as faulty.
Thank you both, Mike
Mike B Drives a 1984 Mk2 Granada ghia V8.
Re: Ign. Pick-up
The connectors on the end of the sensor leads are crimped on spade types - 1/8"? I'd check they aren't corroded where crimped. Trying to guess why the unit would go high resistance.
Dave
London SW
Rover SD1 VDP EFI
MegaSquirt2 V3
EDIS8
Tech Edge 2Y
London SW
Rover SD1 VDP EFI
MegaSquirt2 V3
EDIS8
Tech Edge 2Y
-
- Forum Contributor
- Posts: 208
- Joined: Thu Mar 25, 2010 8:49 pm
- Location: Markfield, Leicestershire.
Re: Ign. Pick-up
Hi Dave,
Good point but not here. When I dumped the original amp from the side of the dizzy I joined a thin 2-core cable to the wiring of the pick-up.
This was done by soldering the two joints and covering them ( insulating ) with heat shrink sleeving. This cable then goes direct to the amp that is positioned well away from engine heat.
however, I have checked my work of 5 years ago and it is still good, nevertheless a good point.
A resistance of 3200 Ohm - still helping produce a spark is beyond me.
Good point but not here. When I dumped the original amp from the side of the dizzy I joined a thin 2-core cable to the wiring of the pick-up.
This was done by soldering the two joints and covering them ( insulating ) with heat shrink sleeving. This cable then goes direct to the amp that is positioned well away from engine heat.
however, I have checked my work of 5 years ago and it is still good, nevertheless a good point.
A resistance of 3200 Ohm - still helping produce a spark is beyond me.
Mike B Drives a 1984 Mk2 Granada ghia V8.