Homebrew

Jason Milldrum on May 18th, 2009

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 [...]

Continue reading about New Homebrewing Finds on the Web

Jason Milldrum on January 11th, 2009

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 [...]

Continue reading about Caddock Dummy Load Performance

Jason Milldrum on January 8th, 2009

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.

Continue reading about Lessons Learned Today

Jason Milldrum on January 8th, 2009

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 [...]

Continue reading about 30 Watt Dummy Load

Jason Milldrum on November 6th, 2008

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, [...]

Continue reading about Progress is Made

Jason Milldrum on November 2nd, 2008

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 [...]

Continue reading about Yet Another DC Receiver

Jason Milldrum on October 26th, 2008

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 [...]

Continue reading about Preliminary CPO Schematic

Jason Milldrum on October 20th, 2008

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 [...]

Continue reading about Back to Basics

Jason Milldrum on July 31st, 2008

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 [...]

Continue reading about W0IYH RMS-to-DC Converter

Jason Milldrum on July 26th, 2008

This morning we had the first Portland-area version of the Pie & Coffee, which we have informally dubbed the Eggs & Coffee since we are meeting at breakfast time. The meeting (and I use the term informally) was at the Peppermill restaurant in Aloha. In attendance was Dave W8NF, Carl WS7L, and myself. Not a [...]

Continue reading about Inaugural pQRP Portland Eggs & Coffee