Re: LOW tx output1.4 volt

Soundararajan Ra.
 

Dear farhan
After replacing Mic i am able to get  1.5 at 100 preset.
But still power out put is below 4 watt.
Driver transistor DC voltage
ground to emitter 440 mv
Ground to base 1.2 volt
Emitter to base 646 mv
pk to pk 7mhz voltage is
Driver base 1.5 volt
Driver collector 1.4 volt
PA gate 1 volt
Checked for short in toroids .
Shall i replace driver transistor.
I have 2N2218A. Shall i use instead of 2N2219A?.
Any it good experience get more exposure in Bitx.
I am enjoying the experience.
Full joy is ,when come on AIr with 8 watt power.
73s
Soundar
Vu2rjw


On Nov 23, 2016 9:30 PM, "Soundararajan Ra." <vu2rjw@...> wrote:

Dear mr farhan
Realy unble to solve my problem
removed predriver transformer and rewound .
Ground to collector 1.1 v
collector to centret tap .5 volt (both supposed to be added and to get 1.5 v)
But CT to ground is .5 volt (c134).
At 100R preset getting .5 v so insufficient drive voltage .
Getting 2 watt out put at antenna.
I am blinking ,what next 7 do.

One more option for me  is to order one more kit.
Soundar
Vu2rjw.


On Nov 23, 2016 4:41 PM, "ik8yfw@... [BITX20]" <BITX20@...> wrote:
 

I performed some transmissions test Yesterday night, I can confirm the values declared: 100 - 90 mA in RX mode, almost 385 mA pressing PTT and over 1.1 A when modulate. Clear audio. I measure over 7 W output on my wattmeter. Fine job. I planning to add a fan to IRF510 for temperature controll. Thanks. Giuseppe, ik8yfw


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