the gauges in these old cars work on a wire that gets hot when current from the sender passes electric current through them, that is why they take time to warm up and read correct.the length of wire drives the needle directly. The voltage regulator works on a similar principle turning the current on a off at a "average" voltage of 9-10 volts. If you did not have a voltage regulatory gauges would go up and down with system voltage ie engine ruining and charging battery and engine off. moden voltage regulators are solid state electronic devises.
The ‘69 has the ignition switch near the gear shift like that. That was standard in ‘69. Although I’ve seen some relocate it to that position. Shouldn’t be too difficult. Just need to lengthen the wires and find a suitable spot to drill a hole.
So … I’m far from an expert … so I could be wrong…. But I think your test equipment is giving you a misleading result. The DIGITAL multimeter is taking a sample of the voltage at some instance in time. And the way the old style stabilizer works is by opening and closing some contacts. When the contacts are closed … you get full battery voltage (~12v). When they are open … you get zip. So unless your multimeter is able to somehow show you the average voltage over time (as opposed to instantaneous). It’s just gonna look like the voltage is jumping all over the place. If you had an analog volt meter … you’d see the needle bouncing up and down as the contact inside the stabilizer open and close. Which is not to say that your stabilizer wasn’t bad. It probably was. But even if it was good … you’d probably still see values jumping all over the place.
A L7810C is a 10 volt regulator. A L7809C is a 9 volt regulator the 10 volt is £1.71 & the 9 volt is £2.60 from eBay you will need a soldering iron! watch out for the tab being earth!
Hi Andy, Dave Connitt here. I want to reply to a couple of your comments on my voltage stabilizer. I don’t use the LM7810 voltage regulator. I use a regulator specifically designed for automotive applications. It has many advantages that the LM7810 doesn’t have like a wider operating temperature range, reverse polarity protection, and over voltage/current protection. Secondly, now matter which regulator you use you MUST include a suitable input and output capacitor to protect the regulator. This requirement is in all the manufacturers data sheets. That is one of the reasons the stabilizers you buy are failing as they just have the regular hanging there by itself. And thirdly, my regulator is thermally bonded to the case to sink heat out of the regulator. In normal operation the regulator needs to supply about .25 amps but these are all linear voltage regulators and they all generate heat which will kill a semiconductor. I’m not trying to be a smart ass at all but just wanted to clarify what you stated. I was a printed circuit designer for 35 years. Before I ship one of my voltage stabilizers it’s burned in for 24 hours at 150% of it’s nominal load.You can use a 7810 but read the data sheet which you can download from the manufacturer for free. Thanks, Da
