Hello Roman,

> Hi Edson, I got 100mA to 120mA with OK efficiency
> even with the little RF choke.

    I've made some tests with 1-2mH inductors, but I've found that it
doesn't regulate very well. R1 seens to make a voltage divider with the load
and as the load increases (turning into a lower resistance), the voltage
drops.

> Any larger inductors were better, especially <1.5uH
> values, I got 200mA with good efficiency out of some
> of them.

    Raising the inductor, the frequency drops and the wave before R1 turns
"more squared". This lowers the stress of Q1 and it works cooler.

> Do you have a cro? It's very easy to tune the efficiency
> if you can see the waveform at the collector of Q1.

    Yes, I do have a good analog scope. It's essencial to study oscilating
circuits.

    As I need beter regulation and high current, I'll try Russell's circuit.

    Best regards,

    Brusque

-----------------------------------
Edson Brusque
Research and Development
C.I.Tronics Lighting Designers Ltda
(47) 323-2138
Blumenau  -  SC  -  Brazil
www.citronics.com.br
-----------------------------------

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