KD0FNR's Amazing San Francisco TouCans Rig -- A Rockmite and a Tuna Topper in a Pineapple Can Mounted on the Dipole in a Shopping Bag

Click on the image for a better look

This post has a definite San Francisco vibe. 

Hamilton KD0FNR appeared on the SolderSmoke blog way back in 2011.  Perhaps he should join forces with N6ASD who lives quite close to him in SF, and seems to share radio interests.  Also in their area is the esteemed Bay Areas blogger and homebrewer Dave AA7EE ; Dave recently sounded the CBLA alarm, alerting us to the presence of an intruder on 3579 kHz.  In the process, Dave mentioned the Pt. Reyes Web SDR, the presence of which came as welcome news to Hamilton. Finally, Dave and Hamilton mention the KPH Web SDR, which brings to mind Dick Dillman W6AWO who has been on the SolderSmoke blog several times.  

Hamilton and his kids have their rig (a Rockmite and a Tuna Topper in a Dole Pineapple can) mounted at the feedpoint of their dipole (in the red shopping bag above).   They link to it via WiFi and Bluetooth. FB.  Thomas Witherspoon has a nice presentation (by KD0FNR) of the TouCans project on his blog: https://qrper.com/2023/12/field-radio-kit-gallery-kd0fnrs-rockmite-20-and-tuna-topper/ 

Hamilton KD0FNR writes: 

At the moment, the kids whose dad I am, better known as the gang—12, 10, and 8 year-old Diaze, Mota, and Tawnse.. all internet aliases—are big into 20 meters QRP CW with Project TouCans, a Rockmite coupled to a Tuna Topper. The radio and the amp that popped us out of QRPp to plain-old QRP are both housed in a Dole Pineapple can with a tuna can as a cover and antenna mount. The whole rig is still very much mounted in our half-wave dipole! 

Project TouCans consists of a Rockmite feeding a 5 Watt Tuna Topper, all of which is housed in our dipole antenna. The Rockmite has a single crystal bandpass filter on it's rx input. That makes it a pretty wide reciever which is fine, but it's particularly sensitive to its tx frequencies, 14075.5 and 14058 kHz AND—for some reason I have yet to understand—10459 kHz. By watching the SDRs that now—thanks Dave—envelope us here at our home QTH in San Francisco, we can see the frequencies of incoming signals. That information keeps me from responding to 14059 kHz signals in vain.

And now, the headphone repeater: TouCans is completely wireless with respect to the ground. That means there's no power line, no feedline, no keyer lines and no headphone line. Keyer controls are handled via wifi to a Raspberry Pi Pico-W on the rig while audio is brought back to my headphones via Bluetooth. Power is provided by a USB-C battery pack that lives in the rig which is mounted above us in the antenna. (Yes, all of this is becuase I thought feedlines matches and baluns were too mystical and hard to understand years ago. Yes, this has probably all been more work than a balun. Yes, I am still totally enamored of my original design decision. :) ) Anyway, the bluetooth range is about 50 feet and the wifi range is shorter than that. The short of it is—pun not intended—that I can't quite use the rig while I'm in my office. But, I can send CQ to the rig every half minute or so via a memory keyer, then turn on the SDR in my office, and then sprint a bit closer to the rig when someone calls back. (It helps that houses in SF are a bit tiny.) So, SDRs are kinda an integral part of our QTH setup and it's awesome to learn about a new—to us—one! Thanks again!

Winterfest Loot: Who Can ID the Homebrew Receiver?

First a big congratulations to the Vienna Wireless Society and its President, Dean KK4DAS.  In spite of low temperatures that made the Winterfest Hamfest live up to its name, this year's 'fest was a big success with excellent turnout both by buyers and sellers.  There were a LOT of older rigs -- on one table I saw three HT-37s.   It was all great. Here is a video of the hamfest.  https://www.youtube.com/watch?v=oheht5jCuKE&t=619s  This was shot early on Sunday morning March 19, 2023, about 30 minutes after it opened.  An hour later there were a lot more customers. 

One of the first things I bought was the item pictured above.  I bought it mostly because we are currently building 40 meter receivers with the local high-school students.  I didn't have a screw driver, so I couldn't open up the box.   Something was rattling around in there.   I worried that the box might be mostly empty.  Or that it would have one PC board with a sad collection of ICs.  But in the hope that I would find something truly homebrew, I bought it.  

Below are pictures of what I found inside.  Can anyone tell us what this is?  ( I recognized it immediately.)  More on this device in due course. 

Other loot from the 'fest: 

The one on the left I've been using since around 1998!  It is getting beat up.  I bought the one on the right at the 'fest.  It is in much better condition.  5 bucks.  TRGHS. 

I always wanted one.  I had nice leather case, but I gave it to Dick Dillman years ago. I now feel like a real boatanchor guy.  I got for 15 bucks.  I see on Amazon they are selling for $466! 

I had one as a kid.  Will be useful in the DR.  In great shape. 

Eamon Skelton's book was a great find.  As were the early editions of SSB for the Radio Amateur.  Eight bucks for the whole lot.

I like homebrew speaker enclosures.  They add soul to the new machine. Perhaps a prize for the high-school project.  Three bucks. 

Finally, this thing.  Plagued by guilt for past cannibalizations of QF-1s,   I was going to pass on this one, but I realized that my friend Dean KK4DAS would be on his way, and if I didn't take it (and extract the variable capacitor) he would.  So I bought it.  But I may leave this one as is, for possible use as the The Radio Gods intended.  It could use some cleaning up.  It seems to have a coat of nicotine. Ten bucks. 

I also picked up a few larger knobs that may be of use with the high-school receivers. 

COVID-19 -- StayInTheShack ("SITS") -- Our Contribution to Flattening the Curve

Early in the COVID-19 Emergency, I saw this inspiring picture of Dick Dillman W6AWO.  Dick had placed a caption under the picture:  "I've moved to the command bunker and will be staying here for the duration." That's the spirit OM!  That is what we as radio amateurs should be trying to do at this point.  That is how we can help flatten the curve and slow the transmission of the virus. 

I guess we could call this  #SITS:  Stay-In-The-Shack.   For many of us this is really not much of a sacrifice -- this is what we mostly wanted to do anyway.  And we have people to talk to (on the air).

So... Follow OM Dillman's lead.  FLATTEN THE CURVE!  STAY IN THE SHACK!  

73 and take care. 

KPH: Maritime Radio History

That's OM Dick Dillman at the controls of maritime radio station KPH in Bolinas, California. Bob, W8SX, sent me an mp3 recording of a show that Dick did for public radio station KWMR. It is about the magic of radio, and about the efforts of Dick and his friends to preserve an important element of radio history. You will also hear about spy stations, the Linconshire poacher, SKY KING and much more. You guys will like this program. It will fit nicely in those iPods and mp3 players:

http://www.g4aqg.sussex.ac.uk/IRT.mp3

More info on station KPH can be found here:

http://radiosquirrels.net/gallery/show?keyword=kphhistory