I am Mike, K7MDL. On this site you will find several of my projects mostly related to ham radio. Interests related to ham radio cover software and hardware design for the VHF, UHF and microwave bands.
RF Wattmeter Project
Multiband LO Project
Is fully configurable with a rotary encoder and 2×16 LCD character display. Uses a radio’s (or N1MM+) BCD band decoder input and translates it to a configurable band decoder output with 6 lines and PTT pass through.
LO level is measured by a 8GHz RF detector. Uses a RF SP6T switch, programmable 31dB attenuator, and a 22dB wide band amp to set the perfect LO drive level for each band. Band decoder outputs can be used to select transverters and select antennas.
N1MM+ OTRSP protocol based Antenna/Transverter Band Decoder Project
The RF wattmeter was a test bed for this subset. The next step is to load this onto a Nano to control 2 sets of outputs with BCD or parallel IO up to 16 values or IO lines for 1 or 2 radios. Uses a single USB connection and some IO buffers. A LCD scxreen is optional.
Ham Radio Station Profiles
I have 5.7GHz and 10GHz at the Camano Island QTH.
Both homes are in antenna restricted neighborhoods so my antennas are hidden under decks, in attics, and I have 6 bands – 50 thru 1296 – in a single tree hidden from view in Florida. I am now about to install a rotator hanging from the back deck in Camano with short yagis on some bands.
WA7TZY became a SK in 2020 and we miss him. He was a talented RF engineer and mentor. With with his XYL Susan, WB7BST, they have enriched the VHF weak signal community for many years of weekly and contest operation.
They also were big HF operators in past years. They have spent years building a very competative station on 11 acres near Woodinville WA. Susan has been the weekly 1296 net control for a very long time now, maybe 20 years?
5.7GHz Transverter Project
It has dual receivers and 90mW out with tunable output filters. Uses PIC 16F877A chip for interface and sequencing. An extra feature I added uses the FT-817 TX Inhibit when the band is not on 430Mhz to prevent an accidental IF overdrive scenario from operation on another band that could be at 5W.
10GHz Transverter Project
My 10Ghz system is based on a MACOM “White Box” conversion to make a 144 to 10GHz transverter. 90mW to a 1ft dish.l A aviation amp module is the LNA. I am using a DigiLO programamble PLL at 2.556GHz driving a converted Qualcom x4 multiplier for the LO. An FT 817 is used as the IF.
I have several ampifier projects in 2020. Both stations got upgrades on 144 through 1296, generally 200W to 500W.