Second Stage Joule Thief Circuits

[Groundloop]

@gadgetmall,

I'm currently populating a Plexiglas plate for your new G-1301-XS Joule Thief.
I'm using a 4500mAh NiMeH battery and is charging the battery now. Has
to hook up the bcap and is almost ready to start testing.

Alex.

[gadgetmall]

Good Deal Alex . i have to get some stand offs and some hardware . I might buy a special case for the third one . for now its hooked up and firing a 1 watt led . Can i ask what is the programmed Voltage  setting for load firing high and cut off volts again ?   Also i tried a dead battery in it and it was charging so the regenerative part is working  as it when i put the new battery in the cap started to charge but its also firing a load when connected , bcap volts are 2.41 and battery is 1.37 .  recharged conditioned ni/mh and starting count down for play time soon . . for now i need to learn  the limits so ill be playing with the 1 watt led and pelitier module  then hook up the actual filament bulbs with a fresh recharged Enigerizer i have conditioned with the Bedini and it hot to trot ! I got almost 7 weeks on the otehr unit without the controller board just doing it manually  and also it was drawing much more than this unit . Draw on this Jt is 3 ma  the 7 week one was 13 ma so i have a good feeling that this will run months i hope . We will see. !! I am going to populate two more if i can snag some surface mount resistors and caps off some junk i have . The Max chips i have , They can also be got FREE from a source i have. The Pic is another story . I might ask Alex if i send some to him with return shipping to program them or there are plans for the  pic programmer here also code included ! It's not that hard to build one .
Update . Batt is still 1.37 and a good sign the circuit is not draining the battery . Bcap will take a long time to get this down to the cut off point of 1.5 volts for the bcap to shut off load so might be tomorrow before i know for sure . I think i will buy some small panel meters to keep tabs on in and out volts and put a piece of lexan on top of this box . i also fused the bcap . I think this important as the high amps could start a fire if something goes amuck !.


Albert

[gadgetmall]

@ ALL  Group Members interested  in replicating this Circuit i Have Some Boards Groundloop made and am offering some to Experimenters who would like to replicate this device . They are unpopulated and i have a limited quantity . If you Pm me i will give you one with the condition that you use it  for replications. Please Serious Replicators only !


Alex . I reread and I am not sure it is operating at the specs . I will repost :Circuit should use minimum current from AA battery.
My circuit uses less than 0,7mA.

Circuit should have a automatically feed back that could charge the AA battery from the BCAP.
My circuit will automatically feed back current to AA battery when AA battery voltage
has dropped to 1,3 Volt (adjustable) AND BCAP has a charge voltage higher than the AA battery.
The base current to the NPN transistor is not wasted and will also charge the AA battery.
The maximum charge current is limited by the transistor HFE (20).
The base current are (5/270)/2 = 0,009 Amp. so max. feed back charge current is 0,185 Amp.
This is a safe charge current for a NiMeH AA battery. (/2 is because PWM control with 50% duty.)

Circuit should have a automatically discharge from BCAP to load.
My circuit will automatically discharge the BCAP to load when the BCAP has reached approx. 2,5 volt.
The discharge will automatically stop when the BCAP reach approx. 1,5 volt. This threshold voltage
was selected bacause we always want the BCAP voltage to be higher than the AA voltage so that
we can get a feed back charge to AA battery when needed. The maximum discharge current is only
limited to the pcb tracks ability to conduct current AND the max. N-mosfet current ability. This is
estimated to be approx. 40 ampere pulsed with 50% duty cycle.

mine is firing around 2.45 i will see if the cut off is within specs . if not could you tell me what i need to do to resolve is anything .. thanks .

Edit . Ok i loaded the bcap down becuase the 1 watt Jt i had connected to the load was just not bring that bcap down fase enuff so i put a load over the bcap . bad mistake there as the bcap eventually dropped to 1.399 and the load switch was still on . i disconnected the load from across the bcap and then the load switch switch off:) Whee! Its charging and the batt is 1.34  so i must have triggered the recharge circuit at the same time the load was firing or something . I know know to ONLY put the load on the load output terminals . It looks GOOD !!! i will start with a fresh charged aa battery and 2 lamps just like yours so we are on the same page . Hey Please check that JT and see if my measurements are off like in the video i did of it . I assume the toroid was not broken because i reinforced it with packing  to protect it this time around . thank you Alex . here it is with the filament bulb and the other lights running is sweet oscillators off !


Gadget 

[Groundloop]

Albert,

The voltage level for "dump to load" can vary a little due to the "spiky"
nature of the JT output. The micro controller will try to do the discharge
at 2,5 volt but noise on the voltage sampling can throw this off a bit. The
important part is to keep the two voltage levels inside the safe operation
area of the Bcap. Tests I have done indicate that it will happen near the 2,5
volt level and the discharge will go on until the 1,5 volt level. This way we keep
the voltage on the Bcap higher than the input battery, and we also make sure
we never over charge the Bcap.

Alex.

[guruji]

Hi Gadget I would like the circuit but don't know exactly how to programme that chip that Groundloop was doing
I already build the charger but it takes quite a long time to charge that Ucap.
Right now I have build the Rosemary heater circuit and doing tests on this.
Thanks
Andrew