You're probably very close to a working rig.
If all you are doing is pressing the PTT button, you won't see any RF going out.
On a single sideband rig, you only get RF to the antenna wen there is audio into the microphone.
If you don't trust your wattmeter, maybe put a 1 watt 50 ohm resistor (or 4 1/4 watt 200 ohm resistors, etc)
on the antenna jack, see if they get hot when attempting to transmit. ?If transmitting 5 watts into a 1 watt resistor,
don't transmit for more than a few seconds or you will cook the resistor.
Be very careful as you mess around, take a break when you get tired.
Put tape over the ends of all the extra leads coming out of that Raduino, don't want them
to brush against anything they should not, such as the IRF510 heatsink.
If the IRF510 heatsink is not electrically isolated from the IRF510 tab, don't short anything to that
heatsink as it is at 12vdc.
Make sure your antenna connector is wired up properly.
Don't laugh, it happens.
On receive, it should be on the order of 150ma (I don't remember exactly) for main bitx40 plus Raduino.
With ptt pressed and no audio, it will go up a bit from there,
Should see about 100 ma (within 20%) ?into the IRF510 drain (connector PA-PWR1) when ptt is pressed.
If it is more than 100ma into the IRF510 with no audio into the mike, stop quickly before it smokes.
If it is less, measure the dc voltage at the IRF510 gate when pressing ptt, and tell us the current into the irf510 and the voltage at the gate.
Be careful if you choose adjust the 10k pot at rv1 as in the wireup instructions, it is very touchy and if you turn it up too hi the irf510 will smoke.
What's worse, it's wired up backwards, so turning it counter-clockwise will increase the bias into the irf510.
Safest thing is to remove power from PA-PWR1 and monitor the voltage at the IRF510 gate while fiddling with rv1
to get a feel for how it works. ?The 100ma point will be at around 3 or 4 volts, the smoking IRF510 point will be maybe 0.5v above that.
Then adjust that bias back down to zero volts, connect back up PA-PWR1 to a 12v source with a 2 amp fuse, and slowly turn rv1 back up?
(counterclockwise!) till get get to that magic 100ma spot.
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On Tue, Oct 24, 2017 at 02:41 pm, Neris Biciunas wrote:
-I have a QRP dummy load (), and the voltage measured (between ground and VRMS pin is something like 0.57) (RF power = (0.57^2)/50= .0065 watts) when the mic is keyed.
