[Review] Convoy C8+ 'Ultra Muggle' - 125lm single mode

[spyderco monkey]

Here's a review I did of a custom Convoy C8+ designed as simple but effective flashlight for giving to friends and family:

https://imgur.com/gallery/N3W3fEu

TL;DR: Using a 1x7135 driver, the light puts out ~125lm for 9.5hrs with full output, followed by another 2 hours of steadily decreasing output. It's very similar in concept to the Malkoff M61L, but for $25.

Because of the highly effective reflector of the C8+, its able to provide excellent illumination at 50yds, and passable illumination out to 100yds.

50yd beamshot:

More beamshots and runtime testing in the link, along with full writeup.

 

[azkid]

Cool concept. I read the imgur writeup.

I wonder if convoy will introduce an "Ultra Muggle" version as an official product. Of course it would have to have a different name.

Edit: just went down the diy programmable rabbit hole. I have been doing AVR embedded development as a hobby for several years. Wouldn't be too hard to reprogram driver boards myself. Also I now kind of want to make my own driver board that is easier to program.

 

[WalkIntoTheLight]

I wonder if convoy will introduce an "Ultra Muggle" version as an official product. Of course it would have to have a different name.

You can kind of do that already with the Convoy biscotti firmware. Just program a mode group with a 10% setting, such as group #3. Then, set the light into mode-memory. Select the 10% output level (which I believe is the right output with a 8x7135 config), and just don't do any mode changes after that. If you have a 4x7135 light, then use a mode group with a 20% output, such as group #5.

 

[Swedpat]

Spyderco monkey,

I like the idea of a no nonsense light with long runtime and decent throw. 125 lm is adequate for many normal tasks while still not that overly blinding if turning the light on with dark adapted eyes. Do you consider to sell some single mode 125lm model I am interested to buy!

 

[freeride21a]

Cool, kinda reminds me of the old Surefire E2L with the single stage 45L output that went for 9hrs of regulated then lasted to 14 as it diminished... iirc actual OTF was around 60L. This was back in 2008-9 or so.

 

[Swedpat]

You can kind of do that already with the Convoy biscotti firmware. Just program a mode group with a 10% setting, such as group #3. Then, set the light into mode-memory. Select the 10% output level (which I believe is the right output with a 8x7135 config), and just don't do any mode changes after that. If you have a 4x7135 light, then use a mode group with a 20% output, such as group #5.

Yes, but if you flash with the light or turn it off and on within a short time it will cycle to next mode. That's not desirable, so I like the idea of a true single mode version.

 

[WalkIntoTheLight]

Yes, but if you flash with the light or turn it off and on within a short time it will cycle to next mode. That's not desirable, so I like the idea of a true single mode version.

Yes, I agree. Which is why I programmed all my Convoy C8's to be single-mode. You can only do that with 100% output, but IMO I want max throw anyway, so it's probably the mode I'd choose even if I could pick others. For lower output, I use an EDC.

I can see the desire for a lower single-mode output, if you want to use only a C8 on a hike. At 125lm, the run-time would be 8 or 9 hours.

 

[badtziscool]

Archimedes lumen curve at play here.

https://www.candlepowerforums.com/v...ictive-is-it&p=4378276&viewfull=1#post4378276

 

[Swedpat]

Yes, I agree. Which is why I programmed all my Convoy C8's to be single-mode. You can only do that with 100% output, but IMO I want max throw anyway, so it's probably the mode I'd choose even if I could pick others. For lower output, I use an EDC.

I can see the desire for a lower single-mode output, if you want to use only a C8 on a hike. At 125lm, the run-time would be 8 or 9 hours.

I considered to order a Convoy C8 last year but I did not because of the lack of reviews(at least at that time).
It's a pity that it's not possible to program to single mode other than highest mode. 1250lm with a single 18650 probably means unregulated, or stable for a few minutes with a stepdown. I have not seen any runtime graph so I don't know. But at 50% it should maintain stable output for maybe 1,5 hours or so.

 

[WalkIntoTheLight]

I considered to order a Convoy C8 last year but I did not because of the lack of reviews(at least at that time).
It's a pity that it's not possible to program to single mode other than highest mode. 1250lm with a single 18650 probably means unregulated, or stable for a few minutes with a stepdown. I have not seen any runtime graph so I don't know. But at 50% it should maintain stable output for maybe 1,5 hours or so.

It is true that the Convoy C8 (8x7135 option) is not very well regulated on max output. My measurements show it losing about 25% output by the time the cell is half-drained. But it should be better regulated on the 4x7135 option, which is essentially 50% output. And if you really want a 125 lumen single-mode, you could always desolder all but 1 of the 7135 chips. Then, 100% output would be about 125 lumens, and it should be very well regulated.

 

[Jimmyboots]

As someone that carries a Malkoff M61L running a 18650 in his work duffle everyday I couldn't approve more of your post and light. Excellent work, now I may have to go over to convoy and order a similar setup.

 

[Swedpat]

It is true that the Convoy C8 (8x7135 option) is not very well regulated on max output. My measurements show it losing about 25% output by the time the cell is half-drained. But it should be better regulated on the 4x7135 option, which is essentially 50% output. And if you really want a 125 lumen single-mode, you could always desolder all but 1 of the 7135 chips. Then, 100% output would be about 125 lumens, and it should be very well regulated.

Thanks for tip! Is that easy done even if I have no experience of modding? And sorry for my ignorance here but is it possible to get a 625lm single mode version as well by desolding chips?

 

[WalkIntoTheLight]

Thanks for tip! Is that easy done even if I have no experience of modding? And sorry for my ignorance here but is it possible to get a 625lm single mode version as well by desolding chips?

I've never done it myself, but AFAIK, those 7135 chips are all in parallel. So, you should just be able to remove them. In your case, leave 5 on the driver, and get rid of the other 3.

 

[spyderco monkey]

Spyderco monkey,

I like the idea of a no nonsense light with long runtime and decent throw. 125 lm is adequate for many normal tasks while still not that overly blinding if turning the light on with dark adapted eyes. Do you consider to sell some single mode 125lm model I am interested to buy!

You can order them directly from Simon at Convoy on Aliexpress.

Send him a link to my Imgur review, and request the same light - A 1x7135, set to 100% 350mah only.

He's great to deal with.

 

[spyderco monkey]

As someone that carries a Malkoff M61L running a 18650 in his work duffle everyday I couldn't approve more of your post and light. Excellent work, now I may have to go over to convoy and order a similar setup.

Thanks! Yes, its very similar to the M61L w/ 18650 in performance. The M61L is a bit brighter, but the C8 has a much larger reflector, so it ends up having a further effective range.

 

[Swedpat]

You can order them directly from Simon at Convoy on Aliexpress.

Send him a link to my Imgur review, and request the same light - A 1x7135, set to 100% 350mah only.

He's great to deal with.

Thanks! :thumbsup: