FS: Pocket Mini Build Kit! - Easy Assembly!

[jayrob]

Senkat, just letting you know that I am sending your Pocket Mini kits (and other item) today. (Thursday)

Thanks!
Jay

 

[enliteneer]

I really want to emphasize studying the information in the link I posted to rog8811's site...

With a red diode/single battery/FlexDrive set up, you won't be pulling extra current to boost voltage, because the diode is only asking for about 2 volts.

Thanks, following the circuit on rog8811's site, I put 4 1N4001 diodes in series with a 1.25 ohm resistor (I didn't have a 1 ohm!). The output voltage from the flex circuit, is 6.45 volts. The 3v power supply (current limited to 400ma) shows the circuit drawing about 50ma. Pretty much the same values as I measured with the real load instead of the 4 diodes/resistor.

According to the diagram, the current across the 1ohm resistor is proportional to the voltage.. I'm reading .005v (or 5ma)... actually I guess it would be slightly less current since my resistor isn't exactly 1 ohm.

Anyways, since the measured output of the flex circuit is the same as when the REAL (single) 650nm diode in place, hopefully the diode may still be good and just needs a bit more current from the flex?

The TI datasheet for the TPS63010 dc/dc converter shows the maximum output as 6.5volts.. which is what I'm measuring. Is this what it should be? I think there's a pot on the circuit (or maybe its just a screw), but if that's not the correct voltage, how can I set the voltage or current output of the flex?

Thanks!

 

[jayrob]

Try something...

Take your 1.25 ohm resistor out of the test load, set your DMM to read mA, and connect your DMM probes like so:

Negative probe to the FlexDrive negative lead, and the positive probe to the silicon diodes, which then connect to the FlexDrive positive lead. (just make sure you have the polarity of the silicon diode string the correct direction according to rog8811's drawing)

This will give you a reading of mA output. Forget about voltage. Voltage does not matter. The diode is going to take what ever voltage it needs. Current is what you want to measure.
Jay

 

[enliteneer]

Try something...
Current is what you want to measure.
Jay

Thanks,

The current thru the 4 diodes (the 1.25 ohm resistor removed) is about 395.5 ma. Which I think is correct, no?

I know you mentioned the voltage doesn't matter, but since I was already setup, I checked the voltage again across all the diodes and I'm seeing 3.6 volts! I'm also seeing about 550ma on the 3v power supply, which was much less than that before! Previously I had measured about 6.5 volts across the 4 1N4001s, the same as when the real diode was in place... I guess the voltage can be all over the place!

I've been hesitant like you said about testing the real diode standalone, but not sure what to do to get this to work!

Thanks!

 

[jayrob]

Also, when testing current in this way, always plug your probe into the 10A input on your meter if you have two inputs. This one will give you a more accurate reading than the 400mA input plug.

But you really have to stop worrying about the voltage readings. (that's what is confusing you) In a FlexDrive build like this, all you have to do is set the current properly.

And then remove the battery, and short the leads together to make sure there is no charge built up in the driver cap, and finally, connect your diode...
Jay

 

[enliteneer]

Thanks,

So sounds like you're saying to hook up the Aixiz module again (after discharging the flex)?

This time, I'll do it on the bench first instead of installing everything and epoxying the heatsink!

 

[jayrob]

Thanks,

So sounds like you're saying to hook up the Aixiz module again (after discharging the flex)?

This time, I'll do it on the bench first instead of installing everything and epoxying the heatsink!

You shouldn't need to use epoxy on the heatsink. Take a look at the build tips in the first post...
Jay

 

[enliteneer]

You shouldn't need to use epoxy on the heatsink. Take a look at the build tips in the first post...

The instructions on the first post, and the printout that came with the hot option kit say:

* As you know, the brass ring will press into the bottom of the pill. Use a little Thermal adhesive here. Maybe just in three spots. (not all the way around, because this is your negative contact point) That way, when you finish the build and go to tighten the assembly into the head, you won't have the problem of the brass ring 'spinning' in the pill instead of everything getting tight.

Is this no longer the case? How does the ring and heatsink stay together when tightening into the housing?

Thanks!

 

[Crossfire]

I press the ring and heatsink together with thumb and forefinger and spin it all up into the head by rotating the head. With a little practice it works very well.

Do not doubt this build. It is legendary. :yh:

 

[jayrob]

I press the ring and heatsink together with thumb and forefinger and spin it all up into the head by rotating the head. With a little practice it works very well.

Do not doubt this build. It is legendary.

Thanks Crossfire!



enliteneer, that instruction for glue is for the brass ring to the host 'pill'. Not the heatsink. Although the pill does contact the heatsink, and in effect is part of the heatsinking, as well as the entire host.

But normally, you will not need any adhesive on the heatsink...
Jay

 

[jayrob]

Darkarmyofone, I sent your Pocket Mini kits (and other items) today. (Tuesday)

:thanks:

 

[jayrob]

Crossfire, I am sending your Pocket Mini kit with 'Hot' option today. (Saturday)

I have it set for 300mA's (red test load) per your request.

Hope your build goes well!

 

[jayrob]

Glutton, I sent your Pocket Mini kit (and other item) today. (Monday)

Thanks!

 

[FlightLevel350]

Hey Jay, how long will these be in stock for? I will most likely get on once I get the money together (sigh, college).

 

[jayrob]

I plan on having these regular...

I keep about 15 on hand.

Just let me know when your ready!

 

[Glutton]

Thanks for the crazy fast shipping Jay! you are no slacker!

I have it in my hands and done already.