PicPower Project Notes

PIC Power Project Notes

The PIC Power Meter started out as an article in QEX in the May/June 2005 edition. A companion piece was presented in QST. In conjunction with the article, KangaUS offered full kits for sale.

Since 2005, over 100 full kits were sold, and another 100+ sets of PC boards. The firmware was updated in 2007 to include some minor feature enhancements, including RS-232 interface support. The project appeared in the 2008 - 2009 handbooks as well (give or take). Bill @ Kanga has just a couple of kits remaining in his stock.

General:

QEX Article reprint.
QST Article reprint.
Silk Screen layout, to assist with the placement of all components.
Original Schematics (requires ExpressSCH / ExpressPCB).
Bitmap of CPU Schematic
Bitmap of Interconnect Schematic
Bitmap of RF Module Schematic

Corrections:

The ARRL Version of the schematic noted two R210 resistors. The lower resistor is R209. These are both of the same component value, and the netlist is correct (so there should be no concern here). (05 June 2005).

Get the Lead Out!

Many components are being obsoleted out, in favor of the Lead-Free or RoHS-compliant efforts. In order to further assist you in the acquisition of components, here is a table of component substitutions. (08 June 2006).

Component Designator	Part Type	Old Digikey Part Number	New Digikey Part Number	Comments
R102	10K Variable Resistor	3329H-103-ND	Work-In-Progress Bourns 3309W?	Lead / Older part was too expensive!
U101, U201, U205	78L05 Voltage Regulator	DK-NJM78L05UA-ND	DK-497-1183-1-ND	Or equiv. Lead Free.
U202	AD8307 Log Amp	DK-8307AR-ND	AD8307ARZ-ND	Or direct from Analog Devices

RS-232:

Schematic of CPU Module, with RS-232 interface added (bitmap)

Parts chosen:

Max 232 Line Driver / Receiver, Texas Instruments, Mouser P/N 595-MAX232DW
1.0uF 50V Electrolytic Capacitor , DK PCE3045CT-ND

The V2.0 code supports serial port output of all of the pertinent data. Note a ugly sprintf bug within the present CCS compiler, which explains the even-uglier formatting within the source code. If you don't like the format of the output, I would encourage you to modify it yourself (I'll probably be doing so as well!)

Presently, the serial output is hard-coded for 9600 bps.

Other Projects to Investigate:

Convert the source code to compiler under Microchip's C18 compiler;

More to follow.

ka7exm at gmail dot com