NICAD Battery charger using LM317 2

[fuseshut]

I have seen many charging circuit examples using various regulators, specifically the LM317T 3 terminal voltage regulator. I wish there was a way i could post this schematic, but I am looking at a configuration that uses the LM317 and output terminal of the 317 is connected to the rechargable NICAD battery. BUT there's another component connection that doesn't make sense. The circuit has a resistor connected from the Positive terminal of the DC input to the positive terminal of the NICAD battery. WHY?
I did some simulations and I can see that the voltage regulator does not supply enough charging current to the NICAD battery when it goes below (let's say) 7VDC (there's a zener voltage regulating diode across the NICAD rated for 8.2V = 1N5345), there is only 75mA. But with that resistor connected from DC in to NICAD Batt, it gives is 3X as much. Is it true in general that based on charging current (mA) requirements the LM317 cannot source enough current? That doesn't make sense either. The LM317 can provide up to 1.5A. If there's a way in which I can post a pdf of this circuit please let me know.

 

[elfgriper]

VE1BLL,
I agree adding the idea of a load at U1 gives some some sense of the current flow thru the circuit. Good Job BrianR.
-elf