Re: Is my BitX output stable?
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Jerry, Raj,
Thanks for?the feedback.? I will try going back to an earlier version and see if that changes things as that is easiest change.? Will then try removal of the 100pf and finally moving antenna to C5/C6 junction (with L3 disconnected).? Do you believe one of
these may also be affectng?the freq output changing (which bothers me more than the volume change)?
The 2nd BitX is still in the box unpacked but maybe it is time to find some space on the bench for another one!
Gene N2IJF
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I'm with Allard (hard to imagine how this is firmware related) and Raj (most likely the BPF at L1,2,3).
Though conceivable that the 100pf cap has something to do with it.
> ?I did not perceive this volume change when running V1.01?
Is it possible it was there with v1.01 but you did not notice
it?
If you have a second Bitx40v3 with original firmware, then check for the same symptom there.
Do all the mods you did to your first unit one by one, checking after each to see if the symptom has come on.
Jerry, KE7ER
On Sat, Nov 18, 2017 at 07:30 pm, Gene Nitschke wrote:
The actual volume out of he speaker (mainly noise) increases significantly (3-4X) while tuning across the range mentioned?.? I only have a 1Mhz USB scope but voltage waveform confirms voltage increase to the speaker.??The increase appears to start after
the 7.200 beep but increases until max range 7.300.? I did not perceive this volume change when running V1.01 but I must admit I have not tried any other versions.??
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My v3?unit is mostly stock with only mods being the?100pf cap to the output low pass filter, and the double diode to protect Q13.? The main reason for upgrading was I was seeing the?freq jumping at the output. The upgrade did not change that so maybe
I should try a down grade of the?SW maybe to something in?between V1.01 and 1.27.1?? I want to keep this one mainly stock as I want to build another for experimenting but want?to get this one?right first.
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