LPF-140 Low Pass Filter Module Completed

The new Low Pass Filter, Model LPF-140, has been assembled and tested on my miniVNA.


It is very similar to the LPF-100 but the inductors and wire are super-sized for high duty-cycle. The input and output are SMA connectors. The control cable is the red vertical rectangle in the upper left corner. A flat cable connects from there to the MPU Module. See the schematic: File Attachment: LPF-140R0 Schematic.pdf (28 KB)

I have been checking out the QVGA Control board for the display. The board is functional. I can run the demo programs, read the USB port and communicate via a serial port. I set up the development in two stages. The first is the Control board using the demo LCD glass. Second is our own LCD board with the two boards sandwiched together. It is 4 x 3 x 0.5 inch size. The glass will pass through the front panel with a thin overlay and bezel. We will be able to control the amp using touch screen technology.

I have the PIC C24 C Compiler installed. The development work on the screens has begun. I found a great little program called VGDD (Visual Graphic Display Designer) from Italy. It is a WYSIWYG (what you see is what you get). This program allows the screens to be made and write the code for you using the MicroChip Graphics Object Library. 

You can see demos of it here: Virtual Fab Site If the link doesn’t work use this: virtualfab.it/VGDD.php

I hope to get a combined set of boards for the Display on order this next week.

I completed wiring and testing Surface Mount Soldering System ,Hot Plate and PID Controller. It has programmed events to ramp the temperature to the sit and soak state followed by the solder melt state and a cool down. I want to have a very repeatable soldering system for the surface mount parts. I think I have it.

Signup for the project. Start by sending me an email: vstamps@comcast.net

73, K5OOR –  Virgil



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