Month: September 2017

More on GM3OXX

Sunset at Luce Bay Scotland, 3cm GM3DXJ, GM3OXX and GM8HEY dishes being set up. Photo GM8HEY (GM4JJJ). 322 km QSO to Wales. 10mW GUNNS WBFM.
Bill,

Thanks again.

I recall when George met up with the team from Wales in a car park in the Scottish highlands , they had also built 3cm gear and he found by direct comparison that their 3cm gear was more sensitive than his. He went straight home and redesigned and rebuilt his receiver. That gear then went on to break the World distance record on 3cm on a superrefraction path from Portpatrick to Cornwall with 10 mW WBFM. Smashing a record that the USA had held for 16 years from mountop to mountain top.

George was ambitious, he wanted that UK, EU and World distance record, he wanted to show the RSGB that Scottish hams could get the 3 countries and 20 counties award on 3cm. We (G8BKE, GM3DXJ, myself and George) did it by travelling round Scotland in my Mini Clubman Estate with dishes and tripods and 3 hams packed in to one car, at the same time fitting in the EU distance record from Luce Bay in Wigtownshire to St David’s Head in SW Wales at 322 km just to show them how.

No VHF Talkback, only a phone call from a telephone box earlier in the day to our Welsh counterparts to say we would be there about 6pm and to tune the 3cm band for us. Frequency uncertainty was in the 10’s of MHz. We arrived at the beach, set up 3 dishes, put on our transmitter test tones and then went back to receive, George asked us to make sure we had our test tones -off- as his receiver was overloaded, it was the Barry Radio Guys he was hearing, they were so strong. Didn’t matter where we pointed the dishes, we were in the sea level duct. Open waveguide still full quieting.

George’s words audible on the remote tape recording made in Wales, ” You can pack up your gear now lads, that’s the European Record!”

Happy Days!

— David GM4JJJ

GM3OXX SK

Bill,

I expect you will have heard via the grapevine, George Burt GM3OXX is silent key. Bad news travels faster than light.

I knew George GM3OXX before I was even licensed in the 70’s, as I heard his broad Scottish accent on 2m AM when he was portable on a local hill and was using 2m to set up 3cm contacts with QRPp WBFM. I climbed the hill and introduced myself and he graciously answered my questions.

George didn’t drive but despite that was able to climb all of the Munros (summits over 3000 feet) in Scotland and operated on 2m from all of them. He used hitch hiking and buses or bicycle to get to foot of the mountains.

Fast forward a few years, I had my first ticket GM8HEY…

I spent a night in my grandfather’s ridge tent on top of Snaefell (the highest mountain in the Isle of Man) (GD) with George. We had planned to take my car to the island by ferry, but had not realized that the TT motorcycle races were on and the Ferry was fully booked. We had to go as foot passengers and reduce the amount of gear. George carried his tripod and dish, 3cm and 2m gear and antennas plus rations etc, I carried this huge ancient canvas tent with wooden poles and pegs. We got to a campsite and we were told it was full, when we asked where the next site was the owner asked us where our motorbikes were, we explained we had come by foot, so he let us pitch our tent after all as we weren’t bikers.

George originally had planned to climb the mountain by foot, but with this huge tent even though I was fifteen years younger than George I would never have made it, so reluctantly we took the mountain railway which goes nearly to the summit of Snaefell.

The previous night it had snowed on the mountain, fortunately it was just freezing cold and windy when we camped right on the top. We had to use rocks to try and hold the old ridge tent down, it had no built in ground sheet. George’s “rations” seemed to be a bar of chocolate and some tea that he boiled on a tiny stove powered by some little pebble sized block of flammable material. I have never been so cold and hungry after a night in a sleeping bag. We idled some of the time calling stations on
2m with George’s homebrew 2m battery powered transistorised transceiver.

Next morning it was too windy to set up the dish and tripod, so we assembled it -inside- the ridge tent and successfully operated from there on 3cm WBFM across to G, GW and GM. on 10mW QRP of course.

George went on to break UK and EU distance records on 3cm before packing microwaves in and going back to QRP on HF.

George was as fit as a mountain goat in his youth, tragically he was struck down with a terrible condition in early middle age that robbed him of his strength and ability to even walk, let alone climb mountains, but you wouldn’t have known it, he never complained, just the same old George “building wee boxes” as he put it to me on one of the last times I spoke to him.

If you visited George’s shack, you wouldn’t find any commercial gear at all, everything he built himself, it was so beautifully made too, I marvelled at how compact and neat it was.

There won’t be another George Mary Three O Ocean X X-Ray X X-Ray on the bands.

Thanks for all the great times George, I am sure you won’t be resting, you are probably designing that next “wee box”.

— David GM4JJJ

Herring Aid Error: C14

Yea, take a look at C14 in the AF amp. At 1000 Hz 10uF is about 16 ohms. That would put a serious dent in the AF gain. And indeed, when I went back to my Herring Aid 5 (38 years from start to finish) and pulled C14 out, there was a dramatic increase in AF gain.

Mistakes happen, but I wonder if anyone else spotted and reported this one. Could someone with access to the QST archives check to see if an Erratum was ever published? The project also appears in the 1977 ARRL book “Understanding Amateur Radio” with the problematic C14. My guess is that it was just an error in the value of the cap.

Can You See an Error in the Herring Aid Five Schematics?

Something caught my eye this morning. Please take a look at the audio amplifier stages (Q3 and Q4) on the Herring Aid Five. Can you see an error? Above is the original schematic from the 1976 QST. Below is a 1998 update by VK1GB and KI6DS. I see the same problem in both schematics. Please let me know if you see an error.

Six Stations Worked on BITX Night

I had a a good session with the BITX gang on 7277 kHz starting at 7pm local last night. Keith N6ORS was on with his MIN-X rig (picture above). Michael KN4EAR’s signal is much improved (Michael had worked Barcelona with his BITX40 Module earlier in the day). Randy WB5YYM’s rig (featured last week on this blog) was booming in from Arkanas.

LOG: WI1B Ken on BITX, AA4PG Pat, KN4EAR Mike in Falls Church, N6ORS Keith on MIN-X, W1LY Willy, WB5YYM Randy in Arkansas

Hallicrafters and the Romantic Life of Private Hogarth

The world of the SolderSmoke podcast and blog are — and will remain — G rated. But occassionally our discussion of ham radio technology causes us to bump up against some racy topics. This happens VERY rarely, and that rarity probably says something about ham radio. We have noted the alleged attractive power of Pete Juliano’s French beret. There was that April 1 story about the new SolderSmoke cologne (“chicks dig it!”). Jean Shepherd was a man of the world — our discussions of him sometimes bring us a bit closer to the prurient boundary line. We occassionally mention the lifestyle of the Dos Equis man. But mostly, we stick to the circuitry.

This morning I came across a character that I hadn’t been aware of: Private (later Corporal) Hogarth. He was the theme of a series of ads run by the Hallicrafters Company during World War II. They were trying to sell their EC-1 broadcast receiver (essentially an All American Five). Their advertising theme was, essentially, “chicks dig it.”

More of this here: http://www.geojohn.org/Radios/MyRadios/EC1/EC1.html


 Don’t blame me. I blame Hallicrafters.

The Road to QRO Perdition


 I want to start out by saying that this is NOT my fault. I have been TRYING to do QRP things. Remember my recent Tuna Tin 2, Herring Aid 5 rig? I am aware of the ever-present threat of expulsion from the QRP HoF. We all remember what happened to poor Pete back on April 1, 2017.

But sometimes people just deliberately put temptation in your path. That is what happened this week. Our old friend Rogier KJ6ETL (formerly known as PA1ZZ) sent me the very LARGE chunk of aluminum that you see in the picture above. Look at that thing. It is practically begging to be turned into a very QRO push-pull amplifier.

At first I told myself that it would be impossible to tap the big heat sinks on the sides. How would I get the drill in there? But then I realized that I can just put the threads in from the outside. I can almost smell the machine oil. And the heat sink compound…

Thanks lot Rogier. This is all your fault.





More Stations Worked on Sunday Night with the BITXes

I worked AD0RW, AC9PD, VE3ZBM and WB5YYM on 7277 kHz around 2345 Z Sunday 10 Sept 2017. BITX ops gather on that frequency on Sunday nights at around 7 pm local time.

The station above is the impressive all HB 40 meter station of WB5YYM. That’s a 49er on the left, and a BITX40 on the right. The amp in the middle has 2 IRF510s. HB mic too. FB

Amazing $49 Rig from QRP Labs

Hans Summers’ QRP Labs has an amazing new rig — The QCX — that is chock-full of features and FB technology. Hans has long been one of the most innovative guys in ham radio, and this latest rig is one of his most amazing creations. Like Farhan’s BITX40 Module, this new rig is priced in the 50 dollar range. Hams who are paying many thousands of dollars for their “radios” should be asking themselves a question: Could I be having much more fun for far less money? This rig is in big demand and there is already a waiting list, so place your order now if you want to work on this during the winter. Here is the link:
http://qrp-labs.com/qcx.html

QCX Features:

  • Easy to build, single-board design, 10 x 8cm, all controls are board-mounted
  • Professional quality double-sided, through-hole plated, silk-screen printed PCB
  • Choice of single band, 80, 60, 40, 30, 20 or 17m
  • Approximately 3-5W CW output (depending on supply voltage)
  • 7-16V recommended supply voltage
  • Class E power amplifier, transistors run cool… even with no heatsinks
  • 7-element Low Pass Filter ensures regulatory compliance
  • CW envelope shaping to remove key clicks
  • High performance receiver with at least 50dB of unwanted sideband cancellation
  • 200Hz CW filter with no ringing
  • Si5351A Synthesized VFO with rotary encoder tuning
  • 16 x 2 blue backlight LCD screen
  • Iambic keyer or straight key option included in the firmware
  • Simple Digital Signal Processing assisted CW decoder, displayed real-time on-screen
  • On-screen S-meter
  • Full or semi QSK operation using fast solid-state transmit/receive switching
  • Frequency presets, VFO A/B Split operation, RIT, configurable CW Offset
  • Configurable sidetone frequency and volume
  • Connectors: Power, 3.5mm keyer jack, 3.5mm stereo earphone jack, BNC RF output
  • Onboard microswitch can be used as a simple straight Morse key
  • Built-in test signal generator and alignment tools to complete simple set-up adjustments
  • Built-in test equipment: voltmeter, RF power meter, frequency counter, signal generator
  • Beacon mode, supporting automatic CW or WSPR operation
  • GPS interface for reference frequency calibration and time-keeping (for WSPR beacon)

Nuclear Powered QRPp? Tritium Nuclear Batteries and Plutonium Pacemakers


OK QRPers, it is time to explore another power source. Enough of the nails in lemons and all that mess. It is time to go NUCLEAR! Check out the motor in the video above, then look at the video below for more info on how the nuclear battery was made. Who will be the first to QSO with homebrew nuclear power? Or has it happened already?

Mike Rainey — this seems like the perfect project for you OM.


Oh and by the way, in the course of reading up on this, I learned that we once used PLUTONIUM to power pacemakers. Check it out:

https://www.mdtmag.com/blog/2016/01/medtech-memoirs-plutonium-powered-pacemaker

And no, today is not April 1.

SolderSmoke Podcast 199 Eclipse, Regen, BITX, DC RX, 3D OLEDS, Iphone Boxes, Mailbag

SolderSmoke Podcast #199 is available.

http://soldersmoke.com/soldersmoke199.mp3

 2 September 2017

 The Eclipse. The Floods.

Sawdust Regen gets John Henry off to a good start.
Voltage regulators as audio amplifiers

 The return of the Simple-ceiver (Direct Conversion)

 Ceramic Resonators

 3D OLEDS

 iPhone Boxes as rig enclosures

 Electric Radio on Frank Jones

 17 Meter Contacts

MAILBAG