Please Listen for my 10 Meter Beacon! 28.2335 MHz

 

There it is, in all its glory.  The transmitter itself is a Doug DeMaw "Lil' Slugger" CW transmitter for 10 and 15.  I built it, maybe 25 years ago?  Still works.  3 Watts out, crystal controlled on 10.  Antenna is a 1/4 Wave groundplane up about 70 feet.  Mike WN2A kindly made me a PIC-based keyer that is generating the CW -- you can see the keyer board attached to the transmitter.  For the base I used a board and some socketry that had previously held a Ramsey-kit Q-AMP 20.  

I have it hooked up now.  It is transmitting.  Please see if you can hear it.  Send me a report!  The frequency is 28.2335 MHz. The callsign is HI7/N2CQR.  I am in the Dominican Republic. 

What Homebrew Looks Like (And W9BRD comment on the High School receiver project)

Clikc on the picture for a clearer view of this fantastic image

Dave Newkirk is the son of Rod Newkirk, the guy who wrote the inspirational "How's DX?" column for QST for so many years.  Dave is obviously a very prolific and proficient homebrewer himself.  I really appreciate his comment on the High School receiver project.  Thanks Dave. 

Dave wrote on QRZ.com: 

Rummaging around the net for such phrases as "TJ receiver" or variations that include AA1TJ and receiver returns no solid hits, but by following clues I found a/the article with schematic at https://hackaday.io/project/190327-high-schoolers-build-a-radio-receiver. That's a well-thought-out design that'll provide fun, fun, fun.

I think I have something like 8 homemade receivers available at the moment at W9BRD, tube-based and solid-state, regenerative and superhet. all told covering 160 through 17 meters (if I include my tube-based and solid-state converters), and about the same number of homemade transmitters. With some exceptions for particular on-air celebrations and events, commonly my entire station lineup is homemade from stem to stern, so to speak.

I've been building radio gear since 1968. Here's some recent fun:

Zed thread covering the development of a converter-plus-regenerative-tuner combo that I came to call the "Super 3-in-9":

https://forums.qrz.com/index.php?th...ceiver-using-one-9-pin-miniature-tube.897249/

Zed thread covering construction of my version of a coffee-can-based receiver/converter combo my father used for 15ish years as his main station receiver after beginning its construction in 1951ish "on a kitchen table in Hartford" while working at ARRL HQ:

https://forums.qrz.com/index.php?th...building-a-160-meter-coffee-can-regen.938709/

To which discussion our own @N2EY kindly posted the mid-1960s "How's DX?" lead in which Dad laid out his station design/configuration/construction philosophy ( https://forums.qrz.com/index.php?th...0-meter-coffee-can-regen.938709/#post-7021505 ).

To us, commercial/mil/pro gear has been and always will be various shades of inspiring to fabulous, but only with homemade gear are we home.

A little Night Radio Romance at W9BRD, featuring the BRD-160CC 160-m regenerative receiver and converter (transmitter and antenna tuner not shown). 

A Saw the Southern Cross (Crux) This Morning (first time in 30 years!)

You can see it (above) in the picture I took this morning, with my Iphone. 

I think I last saw this important constellation more than 30 years ago.  From my observation log: 

DECEMBER 9 1994. MORNING. Went to Parque Mirador Sur near Hotel El Embajador at 5 a.m. Confirmed that I have been looking at the Southern Cross. Below Corvus, Head of the Cross is on a line from Alpha and Beta Centauri. Base of Cross is "three thumbs" from horizon. I calibrate my thumb with Mars and Regulus at 2 degrees. That puts base of cross at 6 degrees off horizon. My Horizon is (90 -18.5 = 71.5 South. So 71.5 - 65.5 BINGO! Agrees with star map declination for Southern Cross. Also Right arm of cross is faint as indicated on star map. Alpha and Beta Centauri off tothe left. Alpha looks red. Beta seems to have two other stars around it. Eureka: Following the line from Alpha and Beta Centauri to the head of the cross, I found a very distinct circular cluster. I think this is the Jewell Box - NGC 4755 (open cluster). Still trying to figure out the constellation (Argo?) that lies to the right of the cross. Looks to me like the false cross. It is bigger than the Southern Cross. Mine seems to have a cluster off the right arm and the left arm has a dimmer star near it. A good morning! (LATER FOUND THAT MY CLUSTER WAS GLOBULAR CLUSTER RNGC 5139. I HAD MISIDENTIFIED ALPHA AND BETA CENTAURI.) 

Here is what Heavens Above predicted for this morning from Punta Cana: 

 

 

Steve G0FUW talks Homebrew and Kits with Charlie NJ7V

Our homebrew direct-conversion receiver challenge (see below) has led to a discussion of the differences between homebrew and kits.  Our intent in designing this rig was to come up with something that was simple enough to actually homebrew (that is the challenge:  homebrew it!) .  Building it from a kit would be something different.  I like the way Charlie and Steve talk about the differences between homebrew and kits in this video.  Around 33:49 Charlie mentions that after a while you just get good at building kits.   Steve points out that building kits is a bit like "painting by numbers" (a great metaphor).  Steve then goes on to talk about the formation in G-QRP of the "scratch-built group." Steve tells us that he has built some 84 radios.  Steve talks about "the joy of building it yourself" (43:49)

Steve gives a very kind shout out to SolderSmoke at around 23:58.    The references to Tony G4WIF and Ian G3ROO were also very nice. And there are many great mentions of Pete Juliano N6QW. 

And remember:  If you are not a member of G-QRP you are just wrong!  Join here:  https://www.gqrp.com/join.htm 

Thanks Charlie and thanks Steve! 

------------------------------------

November 13, 2024

Bill's appearance on the Ham Radio Workbench.  (Bill made some overly harsh comments about radio rejuvenation, and was trying to make amends.)  But now we throw down the gauntlet.  WE CHALLENGE the HRWB guys to build -- to homebrew - our TJ DC RX.  They will experience JOO, JVO and the elite status that comes with having built their own ham radio receiver.  And if they go on to build a 10 minute transmitter, they can use it for CW contacts.  Like on POTA (Thomas!)

December 13, 2024: 

Bill was on Ham Radio Workbench: https://soldersmoke.blogspot.com/2024/11/bill-n2cqr-appears-as-guest-on-ham.html  Our challenge to HRWB.  Gauntlet thrown down... OUR CHALLENGE HAS BEEN GRACIOUSLY ACCEPTED!     We now extend the challenge to the entire SolderSmoke community: Build one of these:  https://hackaday.io/project/190327-high-schoolers-build-a-radio-receiver

Homebrewing is not for the faint of heart!  Accept the challenge!  Build stuff! 

A Tale of Woe -- Troubleshooting my 15-10 Rig in the Dominican Republic

-- Problem first showed up as a low level oscillation in the background.  Annoying. 

-- I suspected the simple AF amp from the TJ DC RX project was oscillating.  Wasted a lot of time. 

-- Isolated the problems by cutting off all of the RF input to the SBL-1 mixer. 

-- While watching the carrier osc signal, noticed that the hum appeared as the waveform got fuzzy. 

-- I had used the osc/product detector circuit from the BITX 20. 

-- I had added an amplifier stage to get the signal to higher level. But it was poorly designed. 

-- After some struggle, I decided to rebuild the osc/mixer board. 

-- Redesigned amplifier stage using LTSpice. 

-- Changed from an SBL-1 mixer to a singly balanced mixer like in the BITX 20. 

-- This worked well.  Hum disappeared. 

-- But I had neglected to put the .001 uF cap to ground from the AF port! Thus the cartoon! 

-- This is a very important cap.  Circuit was a lot more balanced with this cap in place. 

-- Noiticed that output on 10 was only about 25 watts PEP, while on 15 it was around 100. 

-- Checked input to final amps.  Input on 10 was a lot lower.  

-- Tweaked the 10 meter bandpass filter and got the output on 10 up to about 80 watts. 

Re-Built board for carrier osc/BFO and mixer for TX and RX