The Grandson of Zerobeat 3mm LED version with case is an update of the Grandson of Zerobeat kit
which has a daughter board for 3mm LEDs which is mounted in a Davies Molding 220 bakelite box (4" x 2.875" x 1.56")
Grandson of Zerobeat has 9 LEDs which graphically indicate the frequency of a received CW audio tone. Adjust your transceiver's frequency until the green LED lights up and you are within +/- 10 Hz of zero beat with the transmitting station.
3mm LED demo video on Youtube - a short Youtube video of the Grandson of Zerobeat 3mm LED encased kit
The Acrobat files of complex diagrams (like the schematic) may not view well on your computer screen - suggestion: use the magnifier to zoom in for better detail or print out the file.
gzb3mmencman.pdf - an Acrobat file of the 3mm LED Grandson of Zerobeat enclosure manual
gzbraman3mm1.pdf - an Acrobat file of the 3mm LED Grandson of Zerobeat RA manual
gzbra3mmdiag.pdf - an Acrobat file of the 3mm LED Grandson of Zerobeat RA parts placement
3mmragzbsch.pdf - an Acrobat file of the 3mm Grandson of Zerobeat RA schematic
Note: Firefox can't "see" the schematic for some reason, try a right click & save link as to download the schematic and view it with Acrobat
if that doesn't work, please email me and I can attach a copy of the schematic to the reply
gzb ra hu.pdf - an Acrobat file of the Grandson of Zerobeat hookup picture
gzbramodop.pdf - an Acrobat file of the Grandson of Zerobeat RA optional modification ideas