As I mentioned in the previous post, I wanted to try the Google+ Hangouts feature to attempt to do a video chat version of the old EchoLink chat that some of us used to have a few years ago on Saturdays. Today we took it for a spin, and I think I really like how… Read More Homebrewing Hangout
I got a few pleasant surprises this weekend regarding ham homebrewing websites. First off, I received a very nice e-mail from Jonathan, KB1KIX. He stumbled upon my documentation for the Willamette transceiver (AKA the qrp-l.org Group Project), and took the time to do a very nice write-up about it on his blog. There’s a lot… Read More New Homebrewing Finds on the Web
A few days ago, I built myself a simple 30 W dummy load out of Caddock power resistors. As I mentioned in the previous post, I was doubtful about the readings that I was getting from my LP-100 (not that I doubted the LP-100 itself, just my calibration of it). Tonight was my first night… Read More Caddock Dummy Load Performance
You can never have enough low frequency decoupling in an audio amplifier with 100 dB voltage gain. You can never have enough voltage regulation on the VXO you are using to feed your diode mixer. Not enough and you get all kinds of nasty low frequency oscillations in the receiver.
First off, I want to apologize for the sparse updating on the blog lately. The muse has not been my friend in the last few weeks. I try to keep the content mostly original, but perhaps I will have to turn to that time honored blog tradition of short blog posts repeating something cool I… Read More 30 Watt Dummy Load
I finally got a few days of decent sleep (decent meaning more than 4 hours), so I had a little energy to work on the simple DC transceiver. A few days ago, I got the remainder of the audio chain working. The emitter follower on one of the outputs of the differential mixer was yanked,… Read More Progress is Made
Yes, its a post about another simple, low-performing direct conversion receiver. However, I think that this one is slightly unique. I was inspired to give this a try based on the Flea minimalist transceiver that was introduced on the EMRFD Yahoo group. These little rigs are fun to build in an evening, but just how… Read More Yet Another DC Receiver
Here’s quick update to post the schematic of the code practice oscillator that I mentioned previously. As you can see, I just paired a twin-T sine wave oscillator with a buffer amp that feeds directly into headphones. The twin-T provides plenty of voltage, so the buffer is all we need to provide enough current to… Read More Preliminary CPO Schematic
I know that the blog updates have been a bit light over the last week or so. Although we have been in our new house for three weeks now, it seems like the chores just keep piling up. However, I have done a little bit of work in the homebrewing department. Inspired by messages from… Read More Back to Basics
Today I finished construction on the circuitry for the RMS-to-DC converter described on the October 1992 QST article by W0IYH on measuring receiver performance. This is an article that I found on the EMRFD CD when I was searching for information on measuring the noise figure of amplifiers and receivers. I didn’t find the article… Read More W0IYH RMS-to-DC Converter