Q8 modding

1570 posts / 0 new
Last post
kiriba-ru
kiriba-ru's picture
Offline
Last seen: 12 hours 31 min ago
Joined: 01/17/2016 - 02:34
Posts: 1897
Location: Russia
Tom Tom wrote:
kiriba-ru wrote:
Seems that you little mistaken with 7135 usage. It is linear when you have 100% 7135 and 0% FET. All other mods cant be called “linear”. I.E. in ramping you will never catch this situation, even if you stack extra 32×7135 board.

I thought that ramping covered all levels, from lowest (7135 only) to highest. Am I mistaken ?


Lowest is PWMed 7135 which is also not linear (close, but no).
How are you going to catch it? I like linear mod but if I want to use it I will set with 3-5 fixed mods that includes one 100% 7135. After you can add as many chips as you want. But in ramping you will just pass this border (between 100% 7135 and low % FET) and wont recognize this easily.
hank
hank's picture
Offline
Last seen: 1 day 49 min ago
Joined: 09/04/2011 - 21:52
Posts: 8118
Location: Berkeley, California

> Just the zinc chloride

Make sure you understand zinc fume fever“zinc+fume+fever” when you start soldering.

Tom Tom
Offline
Last seen: 4 months 3 weeks ago
Joined: 09/10/2017 - 08:30
Posts: 1163

Zulumoose wrote:
Tom Tom wrote:

It is a big issue for me, have taken a tumble using SRK clone, bad enough but to have no light (and torch fallen from hand) in pitch black, I had a worrying moment. Fortunately backup torch in pocket, so found it.

Lanyard used ever since.

Now that’s the perfect motivation/argument right there to have a lanyard/glow ring/keyring light. All it takes is one trip or slip and you are effectively blind and incapable of finding your light again, assuming it is still working. I have been in pitch darkness outside once where I was incapable of finding my car, just 20m away. A single match would have been invaluable to me.

This was down a steep wooded hillside, eventually found the torch maybe 50 yards below me. Limped home with damaged knee, three butterfly plasters needed to fix. Meanwhile found what I was searching for, thank goodness.

Tom Tom
Offline
Last seen: 4 months 3 weeks ago
Joined: 09/10/2017 - 08:30
Posts: 1163
kiriba-ru wrote:
Tom Tom wrote:
kiriba-ru wrote:
Seems that you little mistaken with 7135 usage. It is linear when you have 100% 7135 and 0% FET. All other mods cant be called “linear”. I.E. in ramping you will never catch this situation, even if you stack extra 32×7135 board.

I thought that ramping covered all levels, from lowest (7135 only) to highest. Am I mistaken ?


Lowest is PWMed 7135 which is also not linear (close, but no).
How are you going to catch it? I like linear mod but if I want to use it I will set with 3-5 fixed mods that includes one 100% 7135. After you can add as many chips as you want. But in ramping you will just pass this border (between 100% 7135 and low % FET) and wont recognize this easily.

Not sure. I heard the switch LED can flash 1, 2, or 3 times to tell you which driver is in use. Until I get mine, not sure how it works. Programming in fixed levels may be the way, if ramping doesn’t give that info.

emarkd
emarkd's picture
Offline
Last seen: 14 hours 19 min ago
Joined: 04/14/2015 - 22:04
Posts: 1598
Location: Georgia, USA

Maybe I’m mistaken, but I was under the impression that there’s not enough pins on the tiny85 to do both the triple-channel setup (extra 7135 bank) and the lighted e-switch at the same time. You have to repurpose that pin to do one or the other. So maybe that’s why we wound up with “only” a 2-channel driver in the Q8?

patmurris
patmurris's picture
Offline
Last seen: 18 hours 15 min ago
Joined: 12/22/2014 - 15:54
Posts: 1327
Location: Nice, France
patmurris wrote:
Tom E wrote:
… I tested the stock Q8’s – if you tap them hard enough on a counter or wood bench on the tailcap, they do shut off, so the beefing up of the springs they were supposed to do maybe improved it a little, but didn’t solve the “jolt test” issue.

What happens when the cells lose contact? Does the light shuts off or does it blink off and resume at the same brightness?

Flashy Mike wrote:
Shuts off. And you have to hit it pretty hard. Don’t see a problem here, at least with new springs.

Oh well… that does not sound too good to me… Most lights just flicker and come back on when having a weak connection, going dark can be a problem in some circumstance. Remind me not to use it for off road biking at night, speleology or anything ‘tactical’.

Tom Tom
Offline
Last seen: 4 months 3 weeks ago
Joined: 09/10/2017 - 08:30
Posts: 1163

hank wrote:
> Just the zinc chloride

Make sure you understand zinc fume fever“zinc+fume+fever” when you start soldering.

Rosin solder is also bad, some are particularly sensitive.

Basically don’t breathe in solder/flux fumes. In production situations there should be at least a desk fan blowing the other way, ideally proper fume extraction (that’s what I’m used to seeing).

Tom E
Tom E's picture
Offline
Last seen: 6 hours 40 min ago
Joined: 08/19/2012 - 08:23
Posts: 12194
Location: LI NY

emarkd wrote:
Maybe I'm mistaken, but I was under the impression that there's not enough pins on the tiny85 to do _both_ the triple-channel setup (extra 7135 bank) _and_ the lighted e-switch at the same time. You have to repurpose that pin to do one or the other. So maybe that's why we wound up with "only" a 2-channel driver in the Q8?

5 I/O pins: 3 chans, 1 switch, 1 SMD LED -- sounds enough to me, and yes, it will work with the latest NarsilM.

Because we don't need an external voltage divider circuit (R1&R2), it's doable. With 2S setups, it's not do-able currently.

 

We are talk'n 1 1/2 years ago roughly when the driver was decided on. Don't recall timing, but if the triple channels with full support (hardware and firmware) came out after the initial submission to ThorFire, then it was too late. For some strange, whacky reason, we thought the Q8 would ship well before the end of 2016 frown.

Ohh btw, I'm thinking the firmware was not ready in time for a triple, because the board layout still has pads for R1/R2.

 

 

 

Tom Tom
Offline
Last seen: 4 months 3 weeks ago
Joined: 09/10/2017 - 08:30
Posts: 1163
Tom E wrote:

emarkd wrote:
Maybe I’m mistaken, but I was under the impression that there’s not enough pins on the tiny85 to do both the triple-channel setup (extra 7135 bank) and the lighted e-switch at the same time. You have to repurpose that pin to do one or the other. So maybe that’s why we wound up with “only” a 2-channel driver in the Q8?

5 I/O pins: 3 chans, 1 switch, 1 SMD LED — sounds enough to me, and yes, it will work with the latest NarsilM.


Because we don’t need an external voltage divider circuit (R1&R2), it’s doable. With 2S setups, it’s not do-able currently.


 


We are talk’n 1 1/2 years ago roughly when the driver was decided on. Don’t recall timing, but if the triple channels with full support (hardware and firmware) came out after the initial submission to ThorFire, then it was too late. For some strange, whacky reason, we thought the Q8 would ship well before the end of 2016 frown.


Ohh btw, I’m thinking the firmware was not ready in time for a triple, because the board layout still has pads for R1/R2.


 


 


 

Yes Tom, I was inside on that discussion, at the time. Wink You’ve come a long way since.

patmurris
patmurris's picture
Offline
Last seen: 18 hours 15 min ago
Joined: 12/22/2014 - 15:54
Posts: 1327
Location: Nice, France
patmurris wrote:
patmurris wrote:
Tom E wrote:
… I tested the stock Q8’s – if you tap them hard enough on a counter or wood bench on the tailcap, they do shut off, so the beefing up of the springs they were supposed to do maybe improved it a little, but didn’t solve the “jolt test” issue.

What happens when the cells lose contact? Does the light shuts off or does it blink off and resume at the same brightness?

Flashy Mike wrote:
Shuts off. And you have to hit it pretty hard. Don’t see a problem here, at least with new springs.

Oh well… that does not sound too good to me… Most lights just flicker and come back on when having a weak connection, going dark can be a problem in some circumstance. Remind me not to use it for off road biking at night, speleology or anything ‘tactical’.

PS: would it be possible to add a proper capacitor in the driver design so that it can sustain short power interruptions? Not the main leds but at least the mcu so that it doesn’t reboot and keeps it’s current state.

kiriba-ru
kiriba-ru's picture
Offline
Last seen: 12 hours 31 min ago
Joined: 01/17/2016 - 02:34
Posts: 1897
Location: Russia

No, this wont work with lvp.

Tom E
Tom E's picture
Offline
Last seen: 6 hours 40 min ago
Joined: 08/19/2012 - 08:23
Posts: 12194
Location: LI NY

I got it on the list to save off the current level setting, and detect short power glitches, then restore the output level. Do-able, just not sure how it would perform, timing wise, if it would recover from these type of hits, etc. This came up near the end and didn't have time to develop, test, get it in. Really wondering now if the stiff springs MtnE sells would prevent it. Problem is though if you have springs stiff enough to work with 30Q BT's, it's probably gonna be too tight for full size protected cells. Actually I didn't try protected cells with the stock springs - may work much better, not sure.

patmurris
patmurris's picture
Offline
Last seen: 18 hours 15 min ago
Joined: 12/22/2014 - 15:54
Posts: 1327
Location: Nice, France
kiriba-ru wrote:
No, this wont work with lvp.

Can you elaborate?

Actually, most clicky switch drivers use power interruption to change state and they do ‘remember’ their state during the time they are off the battery – even long enough for a long press. Banging the light would be a very short event. And many of those can handle LVP nonetheless.

Lazy-R-us
Offline
Last seen: 3 months 3 weeks ago
Joined: 09/13/2015 - 00:30
Posts: 674
Location: Carolinas, USA

patmurris wrote:
Can you elaborate?

Actually, most clicky switch drivers use power interruption to change state and they do ‘remember’ their state during the time they are off the battery – even long enough for a long press. Banging the light would be a very short event. And many of those can handle LVP nonetheless.


I can’t prove it, but given the way the light behaves when bumped this way, I think the processor does not lose power. Consider that when power is first applied, the light blinks twice to indicate this. That is not what I see happening. I think that the code is still running and polling the switch input. It perceives a very short term drop in voltage on that pin, checks what it is supposed to do in the case of a single click and turns itself off.

Lazy-R-us

Tom Tom
Offline
Last seen: 4 months 3 weeks ago
Joined: 09/10/2017 - 08:30
Posts: 1163

There is no intrinsic difficulty in holding up the MCU during very short term power glitches, it’s just a matter of circuit design and bulk decoupling.

It’s something not necessarily done with clicky tail switches (where the driver is looking for power interruptions to change modes), but for an e-switch it shouldn’t be too difficult.

I’ll be taking a look myself, not knowing the detailed design or layout it might be as simple as adding a big bulk decoupler across the MCU, or not.

In my SRK clones its a big problem to fix (I have considered it) because the LED power is also on the same rail/PCB trace as the MCU, so the tens of amps possibly taken by the LEDs exhaust any simple add-on decoupler/holdup cap. instantly. I’d have to cut traces and add a couple of things to improve it. But if the MCU is isolated from the main power by e.g. reverse protection diode, maybe it isn’t too difficult to fix, depending on how the driver PCB is laid out. Shared trace with the LED + supply would be a bummer. I’ll take a detailed look once I have mine, because it really is an issue for me.

patmurris
patmurris's picture
Offline
Last seen: 18 hours 15 min ago
Joined: 12/22/2014 - 15:54
Posts: 1327
Location: Nice, France

Lazy-R-us wrote:
patmurris wrote:
Can you elaborate?

Actually, most clicky switch drivers use power interruption to change state and they do ‘remember’ their state during the time they are off the battery – even long enough for a long press. Banging the light would be a very short event. And many of those can handle LVP nonetheless.


I can’t prove it, but given the way the light behaves when bumped this way, I think the processor does not lose power. Consider that when power is first applied, the light blinks twice to indicate this. That is not what I see happening. I think that the code is still running and polling the switch input. It perceives a very short term drop in voltage on that pin, checks what it is supposed to do in the case of a single click and turns itself off.

I have no idea how this works but what you describe as a fake single click seems to make sense indeed.

Tom Tom
Offline
Last seen: 4 months 3 weeks ago
Joined: 09/10/2017 - 08:30
Posts: 1163

Lazy-R-us wrote:
patmurris wrote:
Can you elaborate?

Actually, most clicky switch drivers use power interruption to change state and they do ‘remember’ their state during the time they are off the battery – even long enough for a long press. Banging the light would be a very short event. And many of those can handle LVP nonetheless.


I can’t prove it, but given the way the light behaves when bumped this way, I think the processor does not lose power. Consider that when power is first applied, the light blinks twice to indicate this. That is not what I see happening. I think that the code is still running and polling the switch input. It perceives a very short term drop in voltage on that pin, checks what it is supposed to do in the case of a single click and turns itself off.

If so, maybe that could be filtered out in firmware, or the e-swtich powered from the same isolated well-decoupled rail as the MCU.

I’m anticipating that when the batteries lose contact with a bump, they will then bounce around a bit, predictable if you know mass of batteries and spring constant. Just as most mechanical switches and relay contacts “bounce”, once you look closely at them.

Edit: if one of the four cells was replaced with a very lightweight part, with a big capacitor inside (maybe supercap), that might be much more resistant to losing contact, even when the main cells do. If it had a small spring on the + end too, even better.

Lexel
Lexel's picture
Offline
Last seen: 15 hours 1 min ago
Joined: 11/01/2016 - 08:00
Posts: 5194
Location: Germany

if you are concerned about power loss when the light get hits you can increase C2 to compensate

Bistro HD OTSM does that to detect long presses of the tailswitch with a 47uF capacitor

Tom Tom
Offline
Last seen: 4 months 3 weeks ago
Joined: 09/10/2017 - 08:30
Posts: 1163

Lexel wrote:
if you are concerned about power loss when the light get hits you can increase C2 to compensate

Bistro HD OTSM does that to detect long presses of the tailswitch with a 47uF capacitor

Might not be so simple if, as suggested MCU is indeed holding up, but false switch presses are being triggered by transients. Glad this little issue, which is important to me, is attracting attention, but will wait until I have my torch before jumping to conclusions.

Edit: PS Lexel, how do your drivers behave in this scenario ? Like the look of your dual 7135 bank ones.

Caleb
Caleb's picture
Online
Last seen: 10 min 12 sec ago
Joined: 03/13/2016 - 01:28
Posts: 578

So much good information here.

Thanks everyone!

Lexel
Lexel's picture
Offline
Last seen: 15 hours 1 min ago
Joined: 11/01/2016 - 08:00
Posts: 5194
Location: Germany

Tom Tom wrote:
Lexel wrote:
if you are concerned about power loss when the light get hits you can increase C2 to compensate

Bistro HD OTSM does that to detect long presses of the tailswitch with a 47uF capacitor

Might not be so simple if, as suggested MCU is indeed holding up, but false switch presses are being triggered by transients. Glad this little issue, which is important to me, is attracting attention, but will wait until I have my torch before jumping to conclusions.

Edit: PS Lexel, how do your drivers behave in this scenario ? Like the look of your dual 7135 bank ones.

from the MCU and its parts for powering the MCU its identical, just one more output channel and a better FET

joechina
Offline
Last seen: 2 hours 22 min ago
Joined: 03/05/2016 - 08:23
Posts: 1405
Location: Germany

@Tom,
what solder do you use for the springs? The stuff for electronics, multicore with 0.5mm OD with 4 percent silver?
Sn60PbAg = 60 Sn, 36 Pb, 4 Ag 180

Tom E
Tom E's picture
Offline
Last seen: 6 hours 40 min ago
Joined: 08/19/2012 - 08:23
Posts: 12194
Location: LI NY

joechina wrote:
@Tom, what solder do you use for the springs? The stuff for electronics, multicore with 0.5mm OD with 4 percent silver? Sn60PbAg = 60 Sn, 36 Pb, 4 Ag 180

I use Kester SN63PB37 #66/44 1.0MM ("44" rosin core), 1 LB spool that been lasting for couple years now, lot more to go. I work with a very senior super tech, who I think is the one recommending this. Right now I'm use no clean solder flux in a pen, but prefer using the better stuff, Kester #186 RMA, but hard to find and seems quite expensive now.

This is one listing for it: http://www.ebay.com/itm/Kester-186-Soldering-Flux-Pen-/122702524233?hash=item1c91a3ef49:g:1PwAAOSwBp5ZuESC

"No Clean" is actually harder to clean up.

Cheaper here: http://www.ebay.com/itm/Kester-Rosin-Flux-PEN-186-good-for-Solar-cells-Panels-/140359491548?hash=item20ae13dfdc:g:3OYAAOSwyZ5Un0xr

 

 

WillyD
Offline
Last seen: 2 weeks 4 days ago
Joined: 10/10/2012 - 15:55
Posts: 779
Location: Ohio

Wow, can’t believe the mod thread is up to 20 pages already. By the time I get my Q8, it will be double this. Has anyone swapped out the emitters yet…sorry…I’m not about to read through 20 pages to find out Smile

tekwyzrd
tekwyzrd's picture
Offline
Last seen: 2 months 2 weeks ago
Joined: 11/14/2015 - 01:15
Posts: 1110
Location: Northeastern Ohio

Re: springs I’m considering using be-cu springs left from my Chimera build as inner springs with outer coated steel springs and punched copper buttons to lock the ends together. The be-cu spring would provide a low resistance path while the outer coated spring would improve compression resistance. I considered using the be-cu springs alone then did a tail impact test of the Chimera and found that after a moderate impact it went off then turbo (lexel 2s tactical dual switch srk driver). The be-cu and steel pair would essentially be using a be-cu spring as the bypass for the steel spring.

Banggood – recommended for buyers who don’t mind an endless wait and continuous excuses for not dealing with defective items.
Fasttech – recommended for buyers who like to wait long periods with ever changing arrival dates for items that were ‘in stock’ when ordered.

hank
hank's picture
Offline
Last seen: 1 day 49 min ago
Joined: 09/04/2011 - 21:52
Posts: 8118
Location: Berkeley, California

Makes sense. The bumping worries me just a bit, as I’d been thinking the Q8 will make one heck of a bike light.

Jtm94
Offline
Last seen: 3 weeks 3 days ago
Joined: 02/22/2017 - 05:08
Posts: 392
Location: Pennsylvania

It would take a heck of a bump to disconnect all 4 batteries. With spring bypasses the wire makes the springs a tad bit stiffer so I don’t know if I can even get my Q8 to disconnect if I tried. Sanding down the battery tube also shaved off a fraction of a mm to make things more snug as well. Thinking of taking the tube down just a bit more to line up the flat spots, but I will wait for my screws to come in so I know the driver is sitting flat.

tekwyzrd
tekwyzrd's picture
Offline
Last seen: 2 months 2 weeks ago
Joined: 11/14/2015 - 01:15
Posts: 1110
Location: Northeastern Ohio
Jtm94 wrote:
It would take a heck of a bump to disconnect all 4 batteries. With spring bypasses the wire makes the springs a tad bit stiffer so I don’t know if I can even get my Q8 to disconnect if I tried. Sanding down the battery tube also shaved off a fraction of a mm to make things more snug as well. Thinking of taking the tube down just a bit more to line up the flat spots, but I will wait for my screws to come in so I know the driver is sitting flat.

The ti-cu springs in my Chimera are 1mm, no bypass. An impact from about 1 ft to impact with the palm of my hand caused stated change. I suspect the method I suggested might prove to be better than a wire or wick bypass.

Banggood – recommended for buyers who don’t mind an endless wait and continuous excuses for not dealing with defective items.
Fasttech – recommended for buyers who like to wait long periods with ever changing arrival dates for items that were ‘in stock’ when ordered.

Flashy Mike
Flashy Mike's picture
Offline
Last seen: 6 hours 54 min ago
Joined: 01/14/2016 - 16:38
Posts: 1172
Location: Germany

Findings with my Q8 lights:

- it’s a disconnect and not a spike or fake key press, easy to recognize: it flashes 2x as it does when powering on,

- disconnects occur with and without spring bypasses,

- disconnects occur with long protected cells and with short ones, but even on weak bumps with short cells.

Flashy Mike
Flashy Mike's picture
Offline
Last seen: 6 hours 54 min ago
Joined: 01/14/2016 - 16:38
Posts: 1172
Location: Germany

Proposal to avoid power off on bumps

An additional 100 uF ceramic cap over C2 appears to be sufficient in my light. No power hickup on hardest bumps, even scratched the tailcap during tests.

Pages