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Re: Is my BitX output stable?


 

?Gene,

> Do you believe one of these may also be affectng?the freq output changing (which bothers me more than the volume change)?

That business of the transmit frequency moving 50khz is very weird,
can't imagine why it would do that. ?

> Pressed PPT with no mic.? Freq meter jumps between 7.2364 and ~7.2911
> (first number stable second varies 50-60 Khz above first).? Is this normal?? Am I just seeing noise??

I'm not convinced this is real,?

A SingleSideBand transmitter with no input at the mike will not transmit anything at all.
Well, a perfect one would not, you will have some residual carrier, but not at all clear if the freq meter
has sufficient signal, or perhaps it is being overloaded. ?Perhaps it is even seeing some other stuff
like BFO or VFO getting coupled in there to confuse things.

Can you find somebody with a shortwave receiver that has a bfo suitable for receiving an SSB signal?
Here's a cheap one: ?
And cheaper still: ?
Or get one of these, I hear the receiver on it is pretty good: ?

I would recommend doing Allard's 10k resistor mod so you can transmit a CW carrier with key down.
That should be a clear tone in any shortwave receiver with a bfo.
If you don't supply power to the IRF510 at the PA-PWR1 connector, you wont be transmitting anything
and won't need a dummy load but a nearby receiver should still hear a signal from Q14.
?
It's possible the BFO or VFO really are moving around, that's the only way this frequency change could be real.
You can listen to our BFO using that same sw receiver tuned to 12mhz. ?With the Bitx40 tuned to 7.2mhz
the VFO will be found on your radio dial at 12-7.2 = 4.8mhz.

Jerry


On Sat, Nov 18, 2017 at 07:58 pm, Gene Nitschke wrote:

?

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