We are down in the weeds with the actual building of the Digital LO/BFO for the new 20M Hybrid Wireless set.
But 1st did you turn off Alexa and did you check your blog, so it is sanitary? We are being watched, monitored and observed thus the concept of the land of the free and the home of the brave is now questionable.
I have been working on modifying the JF3HZB sketch for the new 20M Hybrid Wireless. So far, I am able to show on the face of the display a sideband selection (USB LSB), but the code still needs to work to actually generate two different BFO Frequencies. A single BFO Frequency would work OK if you only wanted one sideband like LSB on 40M or USB on 20M.
A single BFO frequency would also work if you used a pair of filters out of say a Drake rig like a T4XC where the filters are switched in the circuit depending on the sideband you select. Thus, the filters are switched and not the BFO. A DPDT switch would do all of the heavy lifting, with 1/2 of the switch inputting to the ESP32 and the other 1/2 controlling two relays to switch in the different filters.
Yesterday was spent on the start of actually building the hardware. First up was a power supply. The Vin for the ESP32 is 5 VDC and having no 7805 three terminal regulators, I used as LM317 to create the 5VDC.
LM317 connections, R2 is adjustable to set 5VDC
(R2 = 220 Ohms + a 500 Ohm Trim Pot)
CNC Board Layout
A slight adjust will make +5VDC
Once the supply was built and mounted on a board it will fit under the actual Digital LO/BFO,
I made a part fit check of the ESP32, the Si5351 and the breakout headers. See below for the arrangement. Just to left of the top board midpoint you can see the Trimmer Adjust screw to set 5VDC.
Digital LO/BFO above the Power Supply
Final note is that I created an isolated copper pad where I soldered the LM317 to the copper pad and now we have a heatsink. Copper makes for a great heatsink and has better thermal conductivity at 2X!
⚖️ Comparison Table
| Property | Copper | Aluminum |
|---|---|---|
| Thermal Conductivity | ~400 W/m·K | ~200 W/m·K |
| Weight | Heavy | Light |
| Cost | Expensive | Affordable |
| Machinability | Difficult | Easy |
| Corrosion Resistance | High | Moderate |
Them that know, protect themselves. Dump Alexa, Tik Tok, LinkedIn, all social media, (X, and Facebook) and the ARRL. This is so that you create a very small digital footprint.
You might also consider stop making You Tube political based videos as they are being watched by you know who.
73's
Pete N6QW
Do you have any clue who is monitoring you?