[V8] more speedo drivel

[Buchholz, Steven]

... interesting data point David!  I do have a "bad" distributor on the
bench in the garage ... when I get a chance I'll try your trick.  

The one thing I did want to comment on is the use of a 400 ohm resistor.
30mA in addition to whatever load is already placed on the signal at the
other end of the wire might tend to overstress things a bit.  If you can
make things work with a 1K resistor, all the better.  In fact, I'd recommend
something even higher ... say 4.7K.  This will minimize the amount of
current that the Hall Sender is being asked to source ...

The other thing that would be interesting would be to check the voltage
supply to the Hall Sender both when it is loaded (connected to the sender)
as well as open.  If you see 12 volts open circuit that drops to something
like 9v with the load of the sensor applied that would be telling as well.
Either the source has a problem with a high impedance, or the sensor itself
is drawing too much power ... 

Steve B
San Jose, Kaleefohnia (USA)
> 
> For anyone who wants to try this on their intermittent speedo 
> or distributor 
> sender, I tried both a 1K and a 400 ohm resistor. Both 
> worked. I went with the 
> 400 ohm 1 watt for a little extra drive current (around 30mA).