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Dermatophytosis

With eleven Boat Anchors now gone, I found a trove of homebrew radios that have been stashed away. Today was no exception.





Nothing really exotic with a standard single conversion topology utilizing a 9MHz Filter, the SMD version of the Plessey Amps (to the left of the Filter) the 2N2219A Driver and IRF510 final. The standard Arduino Nano and Si5351 comprises the Digital LO and BFO. Well, I must admit my display layout is a bit exotic literally accomplishing the impossible task of 10 pounds in a 5-pound bag.

There are two VFO's (LO's) with memory. A flick of a switch lets me check the 40M FT-8 frequency. It also has a built in 988 Hz, ten second pulsed tone for tune up.

Using the Hermes Lite 2.0 as a detector I corrected the Crystal in the Si5351, so it is dead nuts on, and we get no reports of being 30Hz Low.

The case was repurposed from a former transceiver and uses a recessed front sub-panel. One advantage of using the repurposed case is everything is accessible and plenty of elbow room for tinkering.

As a standalone it does 5 watts and with the AN762 CCI Amp, I see about 120 Watts to the Delta Loop. 

What a pleasure to operate this radio and I take pride in fabricating this rig. It is my design, not a kit and the boards were made using my CNC Mill. 

Signal reports have been excellent and were I a POTA Person, this might be a fun radio to use portable.

Two separate amps are used in line with the BPF. One amp is the Rx Preamp stage, and the other is the Transmit Pre-Driver stage. Their gains are individually adjustable, and this enables slightly reducing the Rx gain, so you don't swamp the downstream circuitry. On Transmit typically you want max stage gain (and linear) to the Driver stage.

The Rx stage is a 2N2219A and the Tx stage is a 2N2222A. These are run hot for best IMD and thus heat sinks are mandatory.

We live in a free society (that is until all of our rights get eroded by you know who) and that enables us to make choices. Imagine a billionaire hedge fund manager who rewarded the ICE shooter who killed the mother of three with a $10K donation to a go fund me that supports the shooter. Our collective choice is to call that out as wrong! 

All along you thought Candida was a rock opera originating from Spain. No singing is involved with that subject.

Them that know can make things go and then they become obsolete and fade away. 

73's
Pete N6QW

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