January 9th, 2024. Who and What do You Trust?
This not about politics or the current political climate in the USA. But it is about Sources of Information.
Guilty on this end of the making the first visit to You Tube to find information. Based on a Research Study I conducted while in Grad School, I found most people retain information when they hear and see information at the same time. Yes, it was a for a Marketing class. You Tube is that venue where you can see and hear stuff at the same time.
Need I also mention -- most of us tend to look for the easiest path. Boom, Click on You Tube and we are watching the subject we wanted,
When I purchased the Seeed Xiao RP2040, You Tube was the 1st stop. I had a link to that video in an earlier blog post. In that video, you were provided a link to a download for the Board Manager. It simply did not work! Then the unthinkable -- I went to the Seeed Studio website and found this.
There it was DON'T USE THIS! My time is really limited and a day's allotment was wasted because I went to You Tube. Another You Tube on the same subject said use the Miyagi LED On LED Off. example in the Arduino IDE.
That didn't work and I think in large, because I was using Version 1.8.5 where the Example Sketches had not been updated for the Xiao RP2040. But the Seeed website did have a proper version which did work and you saw it Blink.
So (as would seem the obvious) go to the manufacturers website as the first step. As I found out You Tube may have outdated information and you waste a lot of time!
Another very Questionable resource is QST! Yes, the supposed Oracle at Delphi of the ham radio world is frequently wrong.. I was given a NIB Eimac 3CX800A7 for use in a linear amp and the source circuit was from a QST article.
The N6QW 20M 800 Watt 3CX800 Linear Amp.
A couple of notes about this amp as it was the 1st use of a Micro-Controller for me employing the Microchip PIC16F84. It all started because I couldn't find a 3Minute Amperite Time Delay Relay. The year was 2000 and I just started seeing projects with the PIC16F84 and thought why can't I use this to build a 3 Minute TDR. Along the left side you can just see the small circuit board with the TDR. [With the Eimac tubes you have the have the tube warm up for 3 Minutes before applying the Plate voltage, thus the TDR. I keep thinking of Mary Jo and the back seat of the 57 VW Beetle and the three minute rule.]
BTW -- Compact was Good and Compact was Bad! Not being really certain about the cooling requirements for the 3CX800A7, I had fabricated a small Plenum Chamber at a local sheet metal shop and oversized the Blower to not chintz on the air flow.
Not having in depth ME skills, I didn't fully realize forcing a large volume of air into a small space is like creating a low frequency Siren. You could not have this compact amp sitting next to the Transceiver as it would drown out the sound. Or if you wore "cans" the sound was transmitted with your signal. The Blower Noise was very obvious.
Today I would have used an Arduino and with a Temperature sensor controlling the Blower speed so that likely most of the time would run quiet. Twenty five years makes a difference. When I had to make a quick move to Southern CA, prompted by the XYL's health issues, I gave this amp to a ham friend. He still uses it on 20M CW.
Back to the Bum Dope in QST. I got to a point in the fabrication where there seemed to be a huge gap in the wiring and the constants needed for the RF Choke were missing. The RF Choke you see in the photo is Homebrew.
I thought it best to track down the author (and not contact QST) for the answer. It was shocking what he shared with me. He built and tested the amp and sent it off to the ARRL Lab along with his notes and an outline of the Article.
He never heard anything more from them until he saw his work in a "cleaned up" version on the front cover of QST. He shared with me that indeed what I was asking was missing from the article but was in his original information submission. Don't trust what you see in QST!
Even in works that I have published there is an issue that we know in our brain about circuit peculiarities and somehow when we read the finished work our brain fills in the blanks, but it is not actually in the paper itself. I employ the 24 Hour rule that before I hit the Send Button I wait 24 hours and take one final read before submission.
Typically publications like the G-QRP Club SPRAT have a higher degree of scrubbing. The technical staff producing the content for publication are seasoned hams and they can spot things those without that background would miss.
