PD68 Review: Convoy BD03 - Tube light w/ built-in charging (Coupon inside)

Obviously Convoy lights in general are very popular. However, of all the Convoy lights the BD series are newer and less known. I have seen some posts in different areas about them (also can be found under the “Dipper” name), but no full reviews. So I asked Gearbest to send me a copy to do a review on.

Fit and Finish
First of all, this flashlight looks like if an S3 and an S8 had a lovechild (see the picture of it with my S8), but since the S3 and S8 are cousins it had a birth defect that allows it to charge batteries inside the light. I was honestly expecting the quality to be a bit below what we expect from Convoy, but it isn’t at all. No, it isn’t the super-matte finish of the new C8, but it isn’t the cheap shiny finish either. It feels great in the hand.

The bezel and button are stainless steel, as is the clip. It is an integrated shelf design, and the reflector is OP. There is no driver retaining ring, it is press-fit. This would normally be a bad thing, but in this case the battery tube is not part of the driver circuit, the power is carried through the battery carrier. The tailcap unscrews normally but the battery carrier comes out with it. The battery carrier itself is plastic, with threads that screw into the tailcap. It also serves as the “retaining ring” for the switch/charger board in the tail. The charging circuit is completely separate from the driver.

I have two gripes: The clip isn’t great. As you can see it’s a wire design that is solid out of the box, but I’m not sure if I can trust it to hold it’s shape. However, in the pictures you can see I put a solarforce clip on it that actually seems to work quite well. The other gripe is this: the battery goes in the “wrong” way. Meaning, positive towards the tail. It’s not really a problem, but I think they should have labelled it better. It is marked inside the carrier, but it’s black plastic and hard to see (maybe a sticker would have been better?). Also adding to the confusion, there is still a spring on the rear, so the positive end goes on the spring. The driver has reverse polarity protection, but I’m unsure about the charging circuit. On the good side, the battery carrier does fit long protected cells (although they are harder to get back out than smaller cells).

Operation
This is a 5-mode driver (L-M-H-Strobe-SOS) with a reverse clicky and memory, so most of you are familiar with the way it operates. It is “only” 1.5amps on high, but it was much brighter than I was expecting. I’m used to always having at least 3amps, so the brightness for 1.5amps was very nice. My sample has the 4C tint, which is in almost perfect neutral white.

The specialness is hidden in the tail. The light comes with USB charger and micro-USB cable (just like for a cell-phone) and a little do-hickey that clips on to the metal button to charge the battery. You don’t even have to open any covers or anything to charge. Very Cool. The downside to this system is that you need to be careful to not lose the little adapter. While charging, a red light can be seen on the tail, and it turns green when charging is “complete”. I tested it using a protected Samsung 30B. On mine, the green light turned on at 4.15v. I then waited an hour and it was at 4.2v, waited another 2hours and it was still at 4.2v exactly, so it appears this is a reliable charger.

Also, the light can be used while charging. The adapter that clips on the tail has a pass-through to operate the switch. I think that makes this perfect for biking. You could have the light attached to a USB power bank while riding for extra long run-times. I did a little test to demonstrate. I put in a battery at 3.82v, attached the charger, and turned the light on medium. I left it running for 30min, then checked the voltage. The voltage had gone up to 3.90v, so essentially this could run forever on medium. I tested it again on high this time (battery still at 3.90v). After ten minutes voltage had dropped to 3.85v, after another 20min, it had dropped to 3.75v. The light is actually running off the battery not the charger directly, so on high you’ll eventually run out of juice, but it should extend run-time significantly.


Mod Forecast: Mostly Sunny
Having the charger separate from the driver sounds great, right? Well yes, but remember the driver isn’t normal. It connects to batt- right in the middle and has a contact ring that connects to the battery carrier for batt+. And unfortunately, there isn’t enough room in the pill cavity to stack a new driver. However, it is a 7135 based driver that has a genuine Attiny13A so you can reflash your own modes on the stock driver and there should be enough room to stack 4 more 7135’s for 3amps. This should also work as a host for a triple with some kind of mcpcb spacer.

Conclusion

Pros:

  • Typical Convoy quality
  • solid construction
  • reliable built-in charger
  • nice beam pattern
  • great tint (4C)
  • 1.5amps is perfect for gifts, it will wow them without burning their hands

Cons:

  • Stock UI (blinkies)
  • Clip isn’t as good as it could be
  • battery orientation should be better marked

Final word: Great light overall, perfect for gifts especially.
.
.
.

Gearbest is offering a coupon code for this light in the different tint offerings.

Link to the lights

For 3B, 4C, or 5B tints the price is $21.99 coupon: ConvoyGB
For 1A or 7A tints the price is $20.69 coupon: BD03GB

I’m heading up to Michigan for the weekend, so we’ll get some real-world usage out of this guy.

Hey pilotdog,

Thanks for the great review! I have been eying the convoy BD03 for a while as the answer for the age old problem of gifting people lithium lights if they don’t have a proper charger, but i’ve held out until someone reviewed it. Good to know that the charger seems pretty safe.

I just have 2 questions if you get the time:

1) Since this is a different driver do you think that it has low voltage warning or some sort of low voltage protection?
Also is there anyway to get rid of those darn blinkies?

2) What’s your take on the reflector? Is it more akin to the deeper reflector in the Convoy S2 and rest of the S series or more like the shallow reflector in the S2+/S3, or is it something entirely different altogether?

Once again thanks for the great review!

1. I didn’t have time to test LVP before I left (maybe i’ll use it enough to find out on my trip) but it does have the voltage divider resistors that would lead me to believe it has lvp, and Simon says it does on his product page. Simon also didn’t mention any way to change mode groups, and there is not a “flash” in any of the modes like there is in Convoy’s other drivers.

2. it is directly in between the S2+ and S2 in terms of depth.

How does the charger works? I’ve been looking at the pictures and it seem to have only 1 contact point, the spring on top of the switch. does it alternate -ve and +ve rapidly?

Thanks for the review, looks well built.

The metal button that you see on the outside is actually two isolated connection points. The middle part (the part that moves when you press it) is what connects to the spring on top of the switch. The outer ring connects directly to the flashlight body and then to the “ground” ring on the charger pcb

I opted for one in 3B directly from Simon. I really like this little light, have been EDC’ing it since it came in. I am a little concerned about the clip as well, I do use the clip all day.

I went 3B since it only had 4 7135’s and I wanted a good color and as many lumens as I could get. Simon also flashed it with no blinky modes. I think that I might like it more that my S2+ 18650, but not as much as the S2+ in 18350. I would love to buy an 18350 tube for this light! Are you listening Simon?

I was not sure how to get the driver out and did not want to bust a paid for light trying. I am having issues with my first charging cap, I have only found one of my many usb cables that will lock in and stay. Simon is sending me another cap, problem solved.

Getting the driver out wasn’t too hard on my sample. There are notches cut and I just used the tip of my DMM lead to pry it out.

I’m really surprised this isn’t more popular than it is, it’s a great little light.

I’d probably prefer this without the charging and the ability to use a different circuit.

Well without the charging its essentially a Convoy S3, so you can have your cake and eat it too.

Appreciate the review on this charger light PD68. I have but one burning question, does the switch provide water resistance like the usual rubber boot?

It’s tough to say. The tailcap is not just metal pieces sliding on each other as it looks, there is a silicone gasket in there. However, it doesn’t have as much pressure on it as the normal boot cover does. So I would say it is definitely water resistant from rain and splashing, but I wouldn’t submerge it.

it says the codes have expired

Sorry for the noob question, but would it be possible to reflash this with something like TK’s Bistro?

Should be. It uses an ATtiny13A microcontroller.

Standard bistro uses the attiny25 but there is a 13 version as well.

Thanks for this info. I’m very happy with this light except I’m not a big fan of the UI and the wire pocket clip sucks. That being said, I appreciate that both ends of the battery tube are identical. This allows me to switch the clip position by reversing the tube. I like when designers avoid making unnecessary mistakes like using different threads at each end. You’d think it would be natural to do, but more times than not, designers seem to choose against it.

Going to try follow the instructions here to reflash the UI to the 13 version of bistro.

Oh good! That’s a great guide to flashing. Helped me out a lot. Let us know the results.