My first VV.

[vereybowring]

So finally got most of the parts I was waiting for, so I have now built my first Variable Voltage device.



It's a 3AA box with two 14500's in series limited by an LM350T and a rotary potentiometer. It also sports the usual copper button and on/off switch along with the eGo 510 connector.

Works very well and the range is 3.7 to 6.87 V which isn't bad.
I am going to get more compact potentiometers and knobs when I get round to making more.

In the meantime I'm off to "test" it out - already my coffee mixes taste much better since it can go to 3A where my PT has only 2A available due to the hub I'm using.

[vereybowring]

Well I've been using it since I built it and have to say it performs reasonably well.

I am glad I put a heat sink on the LM350T though since it gets very hot with ongoing use.
The batteries seem to last about 3-4 hours heavy use too which isn't bad considering with the heating quite a bit of energy must be wasted.

Now I await more parts to play with to get a working model using the TI chip.

[safercigs]

awesome job m8 looking good and with a small nob it will be awesome ...now if you produce these please put me down for 1 for sure

i look forward to further updates

daz

[vereybowring]

Sourcing a smaller dial is not as easy as I thought for a compact unit.

I am chasing up suppliers though since finding "cermet knob" or "cermet shaft" brings back very unhelpful results even within electronics sites.

Wish they would mark things in a more user friendly fashion, cermets are much smaller than other rotary pots but getting them mated to a control is a more difficult proposition since they are designed for screwdriver adjustment.

I have found somewhere though and am trying to get myself a decent deal.

[ian]

Count me in for one of those to mate,please add my name to your list