The 1/4 ohm resistor referenced in the article is a way of simulating a fully-charged battery so the final voltage regulator setting can be made without waiting for the battery to come to full charge specific gravity. The old Sun VAT-20 tester that was the industry standard back in the 50's and 60's has that resistor built into the unit. A quick work-around is to purchase four 1 ohm 250 watt resistors and assemble them in parallel with some #10 wire with alligator clips attached, and insert them in series between the BAT terminal and the output wire to the ammeter like the diagram shows. Then adjust the voltage regulator setting to the desired number (usually 14.5-14.7) Remember that the setting will decrease slightly when you install the cover- - - -steel conducts magnetism better than air. DO NOT try to use the field resistor I recommended for that procedure. It can't be adjusted low enough to get 1/4 ohm, and it might burn out due to insufficient current capacity. 1 ohm 250 watt resistors are available on Ebay, cheap!
That variable resistor is used between the field wire and ground to precisely control armature voltage while setting the cutout relay closing point, or any other time you need a specific voltage output for test purposes. It is not intended to carry full charge current.
The final check of the voltage setting is the water level in the battery. If the engine is starting reliably and the headlights are bright, and you don't have to add water to the battery frequently, you're good to go. If you're running some sort of sealed battery, adjust the regulator to the manufacturer's specifications, but be sure the battery is fully charged or use the 1/4 ohm resistor to simulate full charge before making the adjustment.
Jerry
