Saturday, May 30, 2015

Homebrew Transmitters

It's been a while since I've added any posts that weren't just lists of loggings.

As I wrote in my column for The Spectrum Monitor, I'm about to start building a Corsette transmitter with crucial guidance from Z from Channel Z. I'm not sure if I'll write about it here on the blog, for an edition of the Pirate Radio Annual, or for somewhere else. But I am planning to write about it somewhere.

If you haven't been following the low-powered transmitters that people in the pirate radio community have been building over the past few years, the Corsette is a tiny AM-modulated shortwave transmitter with an output of just a bit more than one watt.

What's the point of such a low-powered transmitter? Well, for starters, Channel Z has been reported across a number of states in the East with just the Corsette. Also, the transmitter is the base for the the Corsair which can output approximately 10 watts, so it has been used by a number of pirates with good results. I haven't heard of amateurs using Corsair or Corsette transmitters on 40m, but that would be a possibility, too. Finally, I'm planning to either back off the power or use it into a small dummy load so that I can transmit audio to my antique radios around the house.

I can't speak for everyone else who has an interest in radio, but I can't just pick up a schematic and understand it. I don't know substitute components and I don't know proper kit construction techniques.

I had wanted to get some good transmitter articles in the Pirate Radio Annual, so I've asked Fearless Fred, Z, and James Brownyard about writing. Everyone expressed interest, but Z said "Why don't you build a transmitter and write about it?" He said that he'd also build one at the same time and help guide me through the process. Well, I couldn't really refuse an offer like that!

I've ordered most of the parts, so I think I'm about ready to get started. I feel as though my utter lack of knowledge in combination with all that Z knows and has experienced, will result in a how-to article that will help newbies be able to successfully build a working Corsette.

*    *    *

Ironically, as I was finishing ordering parts on Friday and thinking about starting the Corsette transmitter project, I received an anonymous hand-written letter at my mailbox. It's a tube transmitter schematic. I won't reprint it here because the designer didn't say whether it was intended for public consumption. I will reprint the note that came along with the schematic:

"A first look at a transmitter we have firing into an array of dummy load cables. Here's a circuit diagram close enough to make up a parts list and hit the bench. Will have more info (and fun results) in a couple of months. Out of ink."

Interesting stuff!

Sunday, May 24, 2015

Memorial Day logs: 5/24-5/25/15


WAZU: 9275.2, 5/24-25, 2345+ Checked out HFU logs, tuned in, & am hearing Stones "Let's Spend the Night Together" at 2345, with a fair signal. My 1st time hearing the station outside of 43m & my 1st time hearing a North American pirate on 31m in a long time. Sounds like Ratt at 0002, a bit earlier, I heard The Seeds "Pushin' Too Hard," which I'm not sure if I've ever heard on a pirate. Fun to hear this test, apparently with low power, and on an odd (but very effective) band.

Saturday, May 16, 2015

Weekend Logs 5/17-5/18/15

I've been remiss in posting logs here, so I thought I'd give it a shot with a couple tonight. I spent most of today at a graduation (Congrats, K!), wrote a couple of entries for the Pirate Radio Annual while experiencing the all-thumbs Pirates of the diamond blow another game as it was pouring here. After it cleared, I ran the weedeater for an hour and checked the radio. I'm hearing:

Radio Cinco de Mayo: 6935U, 5/17, 0005-0021* Lots of  Spanish-language Mariachi music and IDs & e-mail address from a male announcer who might not be fluent in the language. HUGE signal. This could be a broadcast from Radio Diecisiete de Mayo. Announcement at at 0016 was overdriven and the audio clipped badly. Radio Cinco de Mayo was one of the entries that I wrote about an hour ago. I thought I was safe to write the entry, but not so. Great to hear again.

Ireland Radio International: 6299.5, 5/17, 0004+ Heard a tiny bit of audio and a decent carrier. I decided to record Radio Cinco de Mayo instead, with the hope that IRI will still be here after R5dM signs off. I really need to set up a good secondary antenna! Fortunately for me, my bet paid off and RII was still on the air when I tuned back at 0029. It's just barely there in heavy static crashes. Signal has improved here, but it's not as good as what other North Americans have been reporting. I've been comparing it back & forth with the signal on the Twente receiver and it's now getting to the point that I can copy a bit via my own radio without using Twente as a crutch. Right now playing Laurie Anderson "Oh Superman" which is so choppy that it sounds like something weird is going on with propagation (like really fast selective fading or maybe a utility on the frequency). No, it's just the song. Also heard music by Green Day & John Lennon. I didn't hear an address, nor have I found one online. Does anyone have contact info?

Radio Abu Dhabi: 6285, 5/17, 0115+ Much better signal that IRI here! Heard the end of an announcement, then part of a song. Dead air, then into what sounds like folk music with flute 

Went grocery shopping and filled the car up with gas. Came back & discovered that I missed Radio Free Whatever and Wolverine Radio. On the plus side, at least I heard Radio Cinco de Mayo, which typically only makes one broadcast per year and Ireland Radio International, which I've never heard or heard of. 

unid: 6965U, 5/17, 0320-0324* '60s music: "Incense & Peppermints" "Little Red Riding Hood" SSTV of what seems to be a husky or maybe a wolf. During the show, someone threw a carrier on the freq that was so strong, I had to look to see if the receiver had shut off.


Big Johnson Radio: 6935U, 5/17, 1946-1956* Decent signal here with the original version of "10-Inch Record" clear IDs with gmail address (so it was a new or revised show). Haven't heard this station in close to 20 years. Found a few instances of this one being on in '95 & '96. Not sure the last time it was on.

Northwoods Radio: 6935U, 5/17, *2312+ SSTV but the sync is totally messed up, then loons & "Freedom from the Great Lakes" ID. Excellent signal. "Proud Mary," Leningrad Cowboys "Vodka" (sounds like a good band for Radio Free Whatever) + "Fight for Your Right," "Gimme All Your Lovin'" Ha! Jack Pine Savage just said that this is the perfect band for DJ Dickweed. I'm guessing that it was just serendipity & not that JPS is reading my blog while the songs are playing :o)

The Crystal Ship: 6876, 5/18, 0140+ Excellent signal with a song that sounds like Tom Petty. Tuning away to check on Big Johnson Radio. Only caught the last two min of BJR, so I'm back here. More Tom Petty music & heard IDs that this is the TCS Tom Petty Buried Treasure special

Big Johnson Radio: 6950U, 5/18, 0143-0145* Good signal. "Big 10" Record again" YL computer voice: "Write to us at Big Johnson Radio at gmail dot com" Old interval signal, but I can't remember whose it is.

Friday, May 8, 2015

Weekend Loggings: 5/8-5/11/15





Old-Time Radio unid: 6770, 5/8, 2210+ Noted in passing on my way up to listen for Over 60 Degree Radio (but not heard here)