“The Electronics Of Radio” NorCal 40B Transceiver Build Lab Notes: Problems 1 & 2
This may be a series of blog posts you choose to skip over. I am following David Rutledge’s text, “The Electronics of Radio” while building the NorCal 40B transceiver. This series of posts will not be a review of the book, nor is it a assembly manual. Rutledge presents a series of problems at the each chapter that aid in understanding electronics and building the 40M QRP CW transceiver. I am going to try to go through all of these problems and document them here. I will title each post similarly and probably compile them together at the end. Maybe its time for me to include an index on my site, now that I have a couple hundred entries up. We’ll see.
Unfortunately, I think the only way this would be useful to anyone who stumbles upon these would be if you too were reading the book and building the radio. Rutledge labeled his problems 1 through 39, with multiple questions labeled alphabetically (a, b, c, etc.) contained within each problem. I have followed this format.
A couple of pieces of housekeeping…In case you are curious, I am using the Wacom Intuos Pro Medium writing tablet along with the Xournal++ note-taking software to create my lab notes. I absolutely love doing anything that involves handwriting math (including circuit analysis) this way. Secondly, take my solutions with a grain of salt. I am a novice at electronics; all of this could be wrong. I am posting this here, like I always say about all of the blogs on my secret site, for me and me alone. That others seem to enjoy checking in here is neat, but not my priority. If you actually are using this as a resource, keep in mind, none of this may actually be correct.
Finally, the book is still easy to purchase. Currently, you can find the NorCal 40B kit (the replacement for the actually trransceiver used in the book, the NorCal 40A) for sale at this site.
That’s all. The rest are my notes.
KM1NDY
Note: For Problem 2, I used 470 ohm resistors because I did not have 510 ohm resistors.
Below is the amperage measured in the equivalent circuit with 12V going applied to a 120 ohm resister. This matches quite well with what I calculated (see above).
Below is the amperage through one of four parallel 470 ohm resistors. If you multiply this by 4 (once for each parallel resistor in the circuit), you get the 100 milliamps seen in the equivalent circuit (see above). Note, where I have drawn the ammeter, I used the units of amps; it should be milliamps.
