Fixing a Broken LED Strip Tester, TKDMR Model: TD2B

This is a TKDMR Model: TD2B LED Lamp & Backlight Strip Tester that stopped working.
I got this TKDMR TD2B LED strip tester from Amazon for around $19. The first time out using it and 5 or 10 minutes into testing strips of LEDs and it stopped working; I heard a sizzling/frying noise. The voltage dropped from 300V on the display to around 180V. No idea why it happened; I am quite certain I didn’t do anything wrong, nor short anything, because the display would have read 0.0V but it did Not. Nor did I overpower anything because the strips were disconnected from the TV. The silly thing just fried and stopped working, while I was using it to test LEDs, like normal.
Anyway, so I opened it up, and looked around with a magnifier, and sure enough R24 and R25 resistors were fried and cracked, so badly it was hard to make out the numbers on them. It seems they both read 841 which equals 840ohms but because they are both in parallel, you can just solder over them with a single 420ohm resistor. All I had was a 470ohm resistor, so I used that and it worked great! The tester now reads 300V again, just like it is supposed to, and it tests LED strips exactly as before! And with a whole 1/4 Watt resistor now in there, I do not foresee it burning out like the tiny SMD resistors did! Design fail? Yes.
But we can fix it.

Search Results Words: fix, broke, not working, fried, Model: SD300, Jeston Model: DLV300, Yuange Model: YG-300YM