Re: Output stages voltage for reference

Soundararajan Ra.
 

today i fed 19volt to the IRF power supply using laptop powersupply unit. .Power output of 15 to 20 Watt was read in my sx200 diamond swr meter.
Is it necessary to adjust 0 singnal current of IRF (idle current) ?
When i fed 12v volt IRF 510 current is 85ma..

On Fri, Jan 6, 2017 at 4:44 AM, Jorge Luiz Fenerich py2pvt@... [BITX20] <BITX20@...> wrote:
 

      Hello Raj I was able to adjust the 50 mA finally, I was measuring in the wrong place but with your help I hit the point. Thank you.
    Jorge

2017-01-05 11:11 GMT-02:00 Raj vu2zap@... [BITX20] <BITX20@...>:
 

Jorge,

If you measure total current then you will not be able to reduce to zero. If you put a meter only to final stage then
the current control will be effective.

My board came with ~150mA in the final stage IRF.

Raj

At 05-01-2017, you wrote:

 

   Thanks Raj but I can not adjust the 50 mA at rest, something is wrong yes!
    Jorge

2017-01-04 13:47 GMT-02:00 Raj vu2zap@... [BITX20] <BITX20@... >:
 

Jorge,

This is normal. As the final IRF warms up the current increases. Do not worry!

At 04-01-2017, you wrote:
 

    Hello Raj, my BITX20 V3 Linear is consuming 155mA I think a lot, what will be happening? Maybe the auto FET flickering?
     Jorge PY2PVT _._

2017-01-04 10:11 GMT-02:00 Raj vu2zap@... [BITX20] <BITX20@... >:
 
For anyone trouble shooting the final stages.
Measured these voltages without any modulation
Power supply exact 12V, PTT pressed/shorted
Predriver Q13 drawing 30mA
C=11.6
B=3.66
E=3.0
Driver Q14 drawing 41mA
C=11.85
B=1.0
E=0.415
Final Q15 drawing 150mA
C=12
G=4V
E=0




--
  73 de Jorge PY2PVT
  Campinas SP
  GG67MD




--
  73 de Jorge PY2PVT
  Campinas SP
  GG67MD




--
  73 de Jorge PY2PVT
  Campinas SP
  GG67MD


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