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Showing posts from February, 2017

SSB/CW Transceiver Architecture

What is the best Homebrew Transceiver Architecture? This question is almost like your XYL (or girl friend) asking you: "Do you think I am getting fat (or fatter as the case may be)? How in the world do you answer that question (in an honest manner) without getting a lot of blow back.   In some cultures a "plump" woman is highly prized while in others, almost looking anorexic enjoys the same level of adulation. But being the best begs the defining of what is a transceiver architecture?   Having built dozens and by that I mean maybe 4 or 5 dozen, describes the number of transceivers built by me over a nearly sixty year period and thus I have used various schemes. Here are a few:   The first is a bit of a hedge where the project is not really a transceiver but a trans-receiver which means you build essentially a separate transmitter and receiver that share but a few common elements such as a VFO, BFO and some TR switching. In the December 1989...

Like the Geico Ad -- Everyone knows that (--but me)!

A Dinosaur amongst the Technologists! While I try to keep current with the technology trends, regrettably I was born in the Dinosaur era of this hobby and it is hard to shake the past.   A connective story for you (meaning you have to connect the dots) and for this we go back to 1967 when after serving four years in the US Navy, I had my first real job. Should digress that while you would think at this time (Vietnam War) that here I was a degreed EE with his military service behind him that job offers would be a cinch! I applied at Collins Radio thinking my degree, having a ham ticket and military service out of the way would be a plus. Well it wasn't, as serving my country for four years was a handicap. Basically Collins said you have not done electrical engineering for four years and we can hire a new college graduate who has the most current skills AND we can pay him less! Thank you Collins!   When I applied at AT&T Long Lines --they could...

A Practical Problem ~ How to make your hombrew rig do TUNE?

( A note from Pete -- I can see the number of hits on each post and was somewhat surprised that the secrets of homebrewing got nearly 500 hits and the troubleshooting one just over 150. So that is helpful and very telling --we like to build stuff; but don't like to fix it. That is the last time that troubleshooting will be discussed by me. I know how to do it --do you?) How to make your Rig do TUNE? So you asked has Pete been in the house too long because of all the rain in California and now has gone bonkers?  Everyone knows for SSB only rigs (like the stock Bitx40) you simply whistle into the microphone or yell the standard "HOLA"  into the microphone! Others will ask why do you even want to tune your radio? VU2ESE's Bitx40 instructions basically say plug in the microphone and talk it up.   Well having your SSB only rig be able to TUNE has some very practical and necessary applications. The CW ops are smiling now as they think --just hold the key down...

The Art of Troubleshooting!

Three Easy Steps To Troubleshooting! 2/10/2017 ~ See the PS Note at the end. What, are you kidding? There simply are no three easy steps. So get over it! That indeed is the heart of the problem --we all want to slide into home, take the easy way out, do the minimum work, send out 100 emails in hopes of having someone else resolve your problem. It just doesn't work that way! I repeat there are no three easy steps! No fellow hams, this is not Fake News!   That said there is however a process for troubleshooting a project and that is what I will share with you. A long time ago I came up with my process after observing how heathkit was successful in the kit market until they became a dinosaur and were overrun by the black boxes from the land of the rising sun. Heathkit's success was build and test a portion of the circuit before moving on to the next element. In effect the portions completed actually became a part of the test system as you added new elements. Ho...

Gum on your shoe --- the Bitx40

Have you ever stepped in Chewing Gum? The questioned posed is more like the result rather than the question --- no matter what you do it sticks and is just there, never to leave. So it is with my involvement with Bitx40 --- no matter how hard I try, there always seems to be an email in the queue asking me a question. Most recently there have been a flood of questions about the use of OLED displays on the Bitx40.   First asking me has some really negative aspects especially since the information is not being shared with the greater Bitx40 community such as would happen if posted on the Yahoo group reflector. Despite what  I tell my XYL that "I know everything", I don't and thus posing your question via the Yahoo group will give you the benefit of the "group grope" to wrestle with your question. I don't subscribe to the reflector so I may give you info that has been proven wrong.   The other negative aspect is asking me to do work that you should b...

Cool Stuff from N6QW

Cool Radios from the N6QW Laboratories!   2/4/2017 ~ Request for AGC circuit being used. This was supplied to me by PD7SSB who came up with modification to my 20M Shirt Pocket Transceiver Project. It is an audio derived circuit. I have no details for implementing an RF/IF derived circuit such as the W7ZOI Hycas. 2/5/2017 ~ More on the AGC Tribal knowledge here. The 4.7K Ohm Resistor connected to the output and feeding the diode was replaced by a 25K trim pot in series with a 3.3K fixed resistor. I found that there was too much "AGC" action with just the 4.7K ohm as shown on the schematic. The 25K pot was wired as a variable resistor (If you have to ask how to do that --turn off your soldering iron). Thus the range is 3.3K to 28.3K --now giving you a span of adjustments. Hold off  sending me an email as there will be some who suggest just using the 25K pot with one end to ground and the center wiper to the diode and the other end connected to the LM386 ou...

Secrets to Homebrewing ~ Revealed!

Secrets to Successful Homebrewing -- An Art! Many years ago there was a joke going around about the person who widely advertised "Become Rich Quick!" Send $2 and discover how. As the story goes a reply would be received in the form of a postcard ( at that time 3 cents) which simply said "Do What I Did!"    Well I could tell you to do what I have done; but that would undoubtedly be a disservice in that simply repeating what I have done has no guarantee and you didn't even have to spend the $2.   So for free -- you know how good free is -- are some suggestions for the would be or seasoned homebrewer on being successful in your builds.   Getting organized by having a good information storage and retrieval system. A well established library, collections of data sheets, and cataloged project articles are worth their weight in gold A suitable well lit workspace where you can stop a project and return to it later picking up where you left o...