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Old 11-26-2020, 01:51 PM   #51
dl242gt
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Long ago. All cylinders 165+.

I was very concerned of freeze damage to block, radiator, heater core but the only thing I found was the heater core split.
Yeah, good numbers there. It's got to be some spark advance or fuel air related for that thing to run but have no power. I think you are on the right path. Just frustrating with how much stuff was marginal or bad.
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Old 11-26-2020, 02:39 PM   #52
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'Pulse generator' in this distributor... Hall Effect got used in more modern systems.
A Variable Reluctance Sensor might be the correct engineering speak. Short read at cite below.

Hall vs. Variable Reluctance Sensors

"In 1879 Edwin Hall devised a way to measure voltage based on electrons moving on a current carrying conductor in a magnetic field."
===================

Tom's Volvo can be Megasquirted, but I would use a Hall sensor setup since they work at zero engine speed plus .
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Old 11-27-2020, 12:56 AM   #53
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Originally Posted by 84B23F View Post
A Variable Reluctance Sensor might be the correct engineering speak. Short read at cite below.

Hall vs. Variable Reluctance Sensors

"In 1879 Edwin Hall devised a way to measure voltage based on electrons moving on a current carrying conductor in a magnetic field."
===================

Tom's Volvo can be Megasquirted, but I would use a Hall sensor setup since they work at zero engine speed plus .
.
Or in Keep it simple stupid speak... The pulse generator makes an A/C current. Every time the current switches from negative to positive the switch is triggered. We test a pulse generator using the low voltage A/C setting on the Fluke meter.

Hall effect makes an on/off signal. Ones an zeros. More precise.
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Old 11-27-2020, 01:38 AM   #54
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Originally Posted by JohnLane View Post
Or in Keep it simple stupid speak... The pulse generator makes an A/C current. Every time the current switches from negative to positive the switch is triggered. We test a pulse generator using the low voltage A/C setting on the Fluke meter.

Hall effect makes an on/off signal. Ones an zeros. More precise.
Not exactly. Hall effect sensors put out a variable voltage based on the strength of a magnetic field. It would have to be paired with a CT or other threshold sensor to output an on/off signal.

A variable reluctance sensor is similar in application but rather than detecting a magnetic field, it emits a magnetic field and detects ferrous objects. It also outputs a variable voltage which is related to the proximity of the transducer to the object it is detecting.
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I didn't think there was anything to the whole 7/9 thing, but I have to say that my 745T is the only Volvo I've owned that blew up and self-immolated.
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Old 11-27-2020, 10:20 AM   #55
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pulse generator
Both ignition systems are based upon a "pulse generator," and both designs represent an electronic circuit, where one is analog, and the other digital.

Wiki
1. Pulse generator
2. Electronic circuit

Both of these ignition systems used will control the "proper" dwell angle for a given coil, whereas, in a point based distributor, the dwell angle is determined by the point's gap.

Point System - Checking the dwell angle
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Old 11-27-2020, 01:08 PM   #56
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A variable reluctance sensor....outputs a variable voltage which is related to the proximity of the transducer to the object it is detecting.
Ah yes, very important point: Air Gap

Trigger/stator pole air gap: 0.25mm

ECM is expecting a range of lower/higher voltages to operate...he who screws the air-gap pooch will not be within the engineered specification.

PS: Over at Megasquirt forum, one poster used the expression "VR signal."
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Old 11-27-2020, 01:32 PM   #57
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A hall effect sensor is a switch and generates a square wave signal

A VR sensor generates a sine wave signal

A Hall effect sensor is powered, a VR sensor is discrete.
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Old 11-27-2020, 09:26 PM   #58
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A hall effect sensor is a switch and generates a square wave signal
Fine Point - They can produce either a digital (on and off) or analog (continuous) signal depending on their design and intended function.
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Old 11-29-2020, 06:30 PM   #59
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Lol..... Pissing match about archaic ignition triggers.

Tom... Getting anywhere?
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Old 11-29-2020, 08:47 PM   #60
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...archaic ignition triggers....
They are the best at "KISS," and could be fixed quickly. Earlier bike riders learned the hard way what those new fangled Hall sensors were about when they shot craps.

21 January 2019: The great ignition debate: Points vs. Pertronix
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