IF ANYONE knows where to get THIS switch— this IS THE ONE for FET pressure switches on guns. The on/off button acts like a forward clicky— so don’t even need to press the long side of the switch.
Sofirn USED to sell it, and I’m waiting to hear back from Lan/Barry re. availability. You don’t need the tail-cap or plastic wire exit piece (replacing the silicon switch cover) for most lights, if you’re willing to pot whatever switch your light comes with. For the Convoy C8+ : punch a hole in the rubber switch cover, remove the old switch, replace with the FET switch (with any spacers needed) and add silicon— done! (oh and make sure you add the resistor to your driver— more to come on that here… I’m wondering what the best method is for that mod myself)
Have no idea… Sofirn sold it to me last May (with the tailcap for a C8A) and I rebuilt it into one of the C8+ lights— it’s absolutely awesome (after 10 days hunting in the field— using four other different models which all sucked mostly… this one SHINED!). Simon can’t get it, Sofirn hasn’t replied yet, and so I thought I’d throw it out there so someone may be able to ID it— AND provide a source!
Richfire looks like the source to me. Contact them. They also have a 21700 tube style LEP with USB-C charging… linking that in the LEP thread… but anyway they look like they blatantly clone some Surefire and Streamlight designs. Heck, you never know, they could even OEM those two. It’s China after all.
Thanks for the lead… I’ll contact them for an OEM opportunity… but it will be a while to get any info as I’m out for a week starting here in a few days (offline and out of the country)
I looked again and although the switch itself is identical, the wire isn’t coiled like the Sofirn version. But I’d prefer no coiling actually as it gets in the way of things.
Made some prototype . Led directly connected to switch. Full DD power output for 4min , latter starts to drop and in 30sec goes off at Vin 2.8V, at 3V - moonlight, at 4V - 1A. So its like batt indicator and LVP ;)) To recharge you need to turn off for second or few . It works like 1 mode DD. Main driver is unnecessary ;))
So I got my parts in today. Don’t yet have the PCBs so I ‘air wired’ everything. First run with a 1500mah cell @ 3.7V starting lasted 13 minutes before hitting the LVP flash. Retesting with charged cell but thinking something in the 15min is going to be where it lands. I started with a 4.7Mohm gate resistor and the turn off response is just slow enough to cause mode switching to be effected ( off time needs to be a few hundred ms longer than normal ). I’m going to try doubling them up and seeing how 2.35Mohm behaves.
Important note: the 22mm four mode sst40 Convoy driver that I received a few weeks ago works without any additional modification.
EDIT: 2.35Mohm works perfect. Starting the runtime test, but it should be right around 6-7 min.
Good News! I hope the ramping driver used in the C8+ and L21B also come ready to use. But good to know what will be needed if not. Excellent work JaredM!
So the runtime is going to depend on the output level and when it hits LVP on the driver it seems. Since as the capacitor drains, the Vgs decays. Rds-on then climbs an exponential curve as Vcap approaches G-S threshold voltage. On mode 2 of 4 the setup ran over an hour before I cut it short. On mode 4 of 4 (~6A) it ran about 3.5 min. Mode 3 = ~4min. I feel like there is going to be dependencies on the Vf of the emitter too, so I’ll test something high (was using LH351D).
I get some may want longer run-times, but for use on a gun pig hunting (with my hunters and I the last two years), we never run the gun light more than 30-45 seconds at a time when making the kill shots.
When hunting on the move— the usual run time is a few seconds- every five minutes or so to check the field as we move forward to new areas. So about 10-15 times a night (for 1-2 seconds) if stalking for a few miles in woods. But we mostly sit and wait (with night vision) for most hunts and then we only use the gun light to make the kill(s). They are a LOT cheaper than thermal scopes
In any case, when we see a pig the gun turns on and the first bullet is flying 2-5 seconds later- with several shots also sometimes made after that (going after pig #2 and maybe pig #3 if they don’t bug-out too fast). But the party is usually over in under a minute (coyotes are usually one-and-done (10 seconds).
We use hand-held lights for longer views if we need longer light run times (and we often stalk with red lights in the hand, or moonlight also works great if you have it).
So in my use: if this driver can stay on for about a minute with the C8+ and L21B, that is long enough for me. Any longer is “gravy” time
The C8+ CULPM1.TG light runs at 8A (full output) and IIRC the L21B also does 8A at full power (Funtanstic may correct me, while I’m also not sure it’s the same driver/output as the older/heavier L21A).
JaredM if someone needs to modify the driver in order to make the switch work please show us where we would have to add bleeder resistor on the driver?
Not anyone here will be happy to modd their driver in order to make working FET switch… Especially if it is complicated.
I thought it could act like plug and play switch and work without any modifications on the driver? Lexel battery powered fet switch did not required any modification on the driver.
The power has to come from somewhere, a coin cell in the case of lexel’s solution, or the light cell itself through a ”bleeder” resistor connected between Bat+ spring and Bat- ring. On some drivers this can affect mode selection unfortunately.
If you want something universally compatible with no modifications needed then the coin cell is the better solution, with a high pulldown resistor value it will last a very long time before needing to replace the cell.
“On some drivers this can affect mode selection unfortunately”
I have Lexel battery FET switch and my old type of driver lost no memory effect and went to next mode memory…
But I use different single mode driver so mode changing is a matter of past for me. But anyway it would be nice that this works for people that still use multimode drivers
If soldering bleeder resistor to driver is easy like this it should not be big deal in soldering that resistor.
Couple of pictures explains better than thousands of words…
That picture is a valid example of a bleeder mod. On some drivers that may be the best spot, but others maybe not. The only rule is a resistor goes between Bat+ and gnd. Very simple.
I’m not going to buy every driver in the world and test it with this switch. It’s made for modders, so while I will do my best to guide people and answer questions as I always do, I’m not making any promises. For the members buying these in qty to resell, it is ultimately on them to do the R&D to validate what they make and sell. This is a hobby for me, not a business. I do things for fun and for helping out the community, but I have limitations. I’ve already been pretty generous I feel and offered to test a handful of go-to drivers if someone sends me one. Also, my offer still stands for people to pay shipping on the Beta run of boards to test against their products. If you are interested in that PM me. PCBs should show up this week and I could have them out next day.
