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RF Probe circuits and RF Field Strength circuits.? DIY build your own N5ESE Ballpoint Pen RF Probe for cheap.?? Prefer a Sharpie RF Probe, yes we have that one, too.? All 3 circuits complement each other.? NorcalQRP KI6DS rf probe build of Ballpoint Pen RF Probe has a great step by step instruction with clear photos.?? N5ESE Classic has some great descriptions.?? Finally the N5ESE Ballpoint Pen RF Probe, has a great layout blue paper diagram.?? Step by step instructions and pictures for the build, too.?? Look for RF Probe Circuits "Folder"? in the Files section,? /g/BITX20/files/RF%20Probe%20Circuits? you will find these files.?? The file size is 10.1 Megabytes in size.?? Extract and subfolders to a new directory.?? Then ungzip those files and directories.??? Can we have some one make the RF Probe, test the circuits and measure RF Voltage.? Next create a tabbed file with the several columns of the information with circuit junction and transmit voltage measured there.? Place the first information into the first column like RF Voltage measured, 2nd column the device pin name, or the circuit junction.? 3rd column the section name of the transmitter.??? Attach that file here and place a copy in the folder, RF Probe circuits.

ps.? Anybody making a 28.300 Mhz or 50Mhz 6 Meter version??? Anybody coming up with PSK31 interface to the Bitx40 transceiver?

I'd like to see some sort of RF probe built into the main board of the Bitx40 on any new PCB rev. ?At least pads and traces laid out for it, to optionally be stuffed with parts obtained by the user. ?Could be the N5ESE probe, though the $10 AD8307 chip would give far greater dynamic range as suggested in post 20308.?Either way, the DC result goes into a Nano ADC pin.

OK, while I'm on a rant, here's some other debug tools that would cool to integrate into the rig. ?Having such tools available to everyone that owns the board would make debug in the field much easier, and also simplify things considerably when giving help within this forum.

A basic DC voltmeter, going into a Nano ADC pin.

Use a Nano counter-timer output plus resistor attenuator to give a 1khz square wave (better, a PWM sine wave plus RC filter) of known amplitude into the mic input for transmitter testing. ?Perhaps a two-tone test signal?

Use a Nano counter-timer plus a 74HC4040/74HC393 prescaler to implement a frequency counter good to 30mhz. ?It's ok if it takes 30 seconds to get 1Hz resolution.

Use a spare Si5351 channel as an RF signal generator, can be set to any HF frequency. ?A resistor network gives a selection of appropriate signal levels for injection into the various receiver stages. ? (The A and C channels have good isolation and would go to the VFO and BFO, each with their own PLL. ?The B channel is normally shut down to avoid crosstalk, but can use its fractional divider to generate a wide range of frequencies from the BFO's PLL.)

And furthermore!: ?The Si5351 should be on the main board. ? Users can use the preprogrammed Nano and 16x2 display from HFSigs, or choose any uC and display they want. ?The relays strike me as relatively expensive and unreliable, all but the T/R switching into the antenna could easily be done in silicon. ?At ?~10W signal levels, the TR switching could likely be handled as well.

Don't get me wrong. ?The Bitx40 is a real bargain exactly as it is. ?But making some basic debug tools available to everybody that owns the board would give us a common way of looking at things, greatly simplifying incorporated into the design would be cheap and give us a standard way?

Jerry, KE7ER

The prescaler and especially the AD8703 stuffing options are admittedly a bit over the top. ?The audio and RF signal generators and the RF probe would likely cost pennies, it's all R's and C's and a cheap schottky signal diode for the probe. ?Would help solve many of the debug issues we see in this forum. ??

Jerry