I really struggled with a recent BTU Shocker mod/upgrade - disappointing output, disappointing amps from the BTU driver, even with a resistor mod. Removing the resistor made no difference... What do I do? How do I explain to the owner after all the cost and time, only 10% improvement?
So, I reverted back to what worked once before... Swapped in this driver from Hank: IOS_3.5A. It's a little messier installing - slightly undersized, had to add some copper strips and solder to be sure it gets tightened down well, because the original driver is like 22 mm, this IOS driver is 21 mm or so and a thinner contact board. Got it in, with the usual XM-L2 U2/SinkPAD, 20 gauge, lapped, surfaces, copper braid on springs, yada, yada.
On KeepPower 3400's, got a respectable, though not stunning 3.55A measured across the switch, with lumens of 3,753 @start, 3,627 @30 secs. Then also copper braided the + and - springs on the carrier (not just the 3 cell springs), and it improved to 3.76A @switch, lumens of 3,876 - 3,740, throw of 178 kcd. So, seeing a pattern ofreducing resistance and getting improved amps, I tired 3 fresh SONY 30 amp rated batteries (from FT). This is the result:
5.0 amps measures across the switch, lumens: 4,760 - 4,461, throw 212 kcd (throw # is low because measured at 4.3 meters).
Wow - this blew me away! Ok, it's not a realistic use scenario - the SONY's are 1600 mAh unprotected. But it does show the potential, and if say you want that "wow" effect, you may get 15-20 mins or so on high I'm guessing? It's probably even better on Samsung 20Q's or 20R's, and I tried Panasonic PD's (not fully charged) and got a respectable 4.46A measurement and 4,386 - 4,192 lumens, and at 2900 mAh, you could get decent runtime but are gambling with unprotected batteries in series. I ran the light for 3 minutes straight and all went well, slightly warming of the body in the area of the pill.
So, this IOS driver is going direct drive in high, though medium and low still work fine. Advantage is no auto kick down from "turbo" also. I emailed Hank about this 3 batts/3 LED's series configuration earlier before using it, and he already speculated it may go direct drive, so now it's pretty much proven on this Shocker. I would also assume you may be able to get the same result on a DRY driver with all the same mods (copper braiding, 20 gauge wire, copper stars, etc.). I did one Shocker upgrade with a DRY driver and got 3,944 lumens @30 secs and 190 kcd on Panasonic PD's, but not sure if I copper braided all 5 springs in the carrier, and don't have a recorded amps measurement to confirm it.
Updates (Aug 20)
Fixed up my amp measurement leads - now using 14 gauge silicon wires. So on the Shocker I'm working on now has de-domed XM-L2 U2 1A's on Noctigons, measured 4.7A on Panasonic PD's, 5.7A on SONY 30A and Samsung INR 20Q's, and absolute insane #'s for lumens and throw at 5.7A: 4,100 lumens at 30 secs, 467 kcd measured at 4.3 meters. Now there's a couple of differences - I jumpered the current limiting resistors (jumper wire over one resistor), cleaned up contact surfaces with CRC 2-26, using emitters/stars from IOS (known good!!).
- 6.5 minute test: 118F at hottest surface (pill area), cells down to 3.8v, 4.1A switch measurement
- With KeepPower 3400's: 4.15A with cells at 4.10v, still warm, lumens: 3,478 at 30 secs, throw: 392 kcd