Wow, this is getting tiresome. I had another voltage stabilizer in my TR4A go
bad.
The first was my 39 y/o original, then a new one (actually a TR6 model) and
then a new TR4A model.
The original failed "open" (I.E. the gauges were getting no power.)
The TR6 model failed closed (I.E. the gauges were getting unregulated 13.6v)
The latest seems to have failed mostly open (The gas gauge reads about 1/4 when
it is tip-top full, and the temp gauge is full cold).
My original unit is easy to get open and did so. The little resistance wire
gets quite toasty after I cleaned the contacts. But it does not seem to open
the contacts properly when it gets hot. I get a little flickering of an LED
that I have hooked up to the test circuit. I had expected ON for a several of
seconds and OFF for something slightly less than a second. But this is not
what I see.
So, 2 questions. 1) what ON/OFF frequency should I expect for a properly
functioning stabilizer, since I do not have a good one to test. 2) what
should be making these things go bad and do it in DIFFERENT ways? As far as I
can tell, the gauges are working correctly and the resistance of the gauge
circuit seems OK. I am not sure what kind of current draw they are supposed to
have, but it seems OK at first glance. THe last stabilizer lasted maybe 300
miles, if that.
Interesting electronics side note: When I was awaiting a spare stabilizer many
months ago, I threw together a linear 10V regulator. It had NO power
filtration/spike protection, not that I thought I would have many transients.
Well, WRONG. The regulator died in several hours of running, but was great
while it lasted. I think I might make a new, more hardy one. Maybe with a
1000V/1A diode feeding into 1000uF cap on the power input along with a 600W
20-something volt bidirectional TVS as well. Does anyone know if this will be
enough protection, or is there something more I should have on it?
I had considered the issue of the relative ly poor efficiency of a linear
regulator, but, you know, the stabilizer's resistance wire probably dissipates
a half watt or more. That is probably about 2% of the entire output of my
generator's full power output!
-Tony
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