A new K2 power issue?

[gary7]

I am bring a new K2 into the world and I have completed my steps up to P67. Ready for 'Assembly, Part III'. I am an experienced builder and have a generous assembly and test bench. One thing I noticed, when I turned the unit on for 'Alignment and Test, Part II', the K2 was drawing 240mA rather than the 80mA in my first turn on. As this is more than the unit should draw when finished I do have some concern. The only part that seems to be getting warm is Q22 which appears normal, but there seems to be 100mA lost (almost 100% more than the 120mA nominal).

As I am not the first to build one of these, I hope there might be some ideas out there. I am not sure if this is normal for this stage or there is something wrong.

Thanks,

Gary
KJ4ZMP

[picmaster]

Hi Gary,

I have built only 1 K2, but mine has the same power consumption (240mA)
during RX. So I think your current consumption is OK. You can have some
deviations of your consumption because of LCD backlight mode (day/night),
S-meter mode (bar vs dot), post-mixer amp Q22 biasing so don't worry too
much about this.

Keep in mind that if some of your 2N7000s used in the T/R switching circuit
were fried during assembly (like mine for example), it's possible to have both
RX & TX circuits activated (during reception!) and thus consuming more current
than expected. Just check the voltages on the drains to be sure MOSFETs
are healthy.

Wish you success in your build!

73,
Nikolay (LZ1NRD)

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