Re: share your BITX success stories

ajparent1/kb1gmx
 

Well took it out of the box and wired up the connectors and all and having on the bench spread out.
haven't measured power in any exacting way for at 11V I see 6W at 7mhz.  Receives well.

I then installed my mod for the audio amp to run it at 8V regulated.  It works.  Only one part
used an lm7808.

Changed the resistor on the back of the LCD from 100ohms to 330 to damp down the brightness a bit.
Adjusted pot on the back of Raduino for better contrast.
Flipped the 5V regulator around so it doesn't hang off, my case needed that bit of space for a really
good encoder.

Next step is the bias on Q70 its sitting at 1.6V way too low for good overload results. 16k resistor will fix that.

After that replace q90 with 2n2222A and then check the bias it seems to be at higher current than needed.

At this point I'll break for an order of a dozen MPSH10 and some other RF parts to try.

The case, no matter what they say the drillin and blastin is the work:
While waiting I'm working the fitment of the case and the various parts.   Other things that
will need to be on the panel is the power led, some form of metering for received signal
strength and relative TX power (bargraph but not on LCD). 
Mic jack, headphone, and antenna jack are  on the front panel along with LCD and power
switch.  Then we have audio level and rf-gain.  All this goes in an area 8.x inches by 2.25 inches.
It has the potential for being cramped if I use the larger tuning encoder.   The display
eats panel space too.

plodding on..

Allison

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