Monday, December 20, 2010

Χάρις


Happy he alone, who each night can say,
“My life is lived: the morn may see
A clouded or a sunny day:
That rests with Jove: but what is gone,
He will not, cannot turn to nought;
Nor cancel, as a thing undone,
What once the flying hour has brought.
Quintus Horatius Flaccus (Horace), Odes; 3:29, 23 BC

Happy the man, and happy he alone,
He who can call today his own:
He who, secure within, can say,
Tomorrow do thy worst, for I have lived today.
Be fair or foul or rain or shine
The joys I have possessed, in spite of fate, are mine.
Not heaven itself upon the past has power,
But what has been, has been, and I have had my hour.
John Dryden, Happy the Man, 1685 

"Gratitude rejoices in what has taken place or in what is. It is therefore the opposite of regret or nostalgia (which aches for a past that never was or is no more)...

'The fool's life,' says Epicurus, 'is empty of gratitude and full of fears; its course lies wholly toward the future'...The wise man, on the contrary, takes delight in living and also rejoices in having lived. Gratitude (χάρις, or Charis) is this joy of memory, this love of the past - it neither suffers over what no longer is nor regrets what has been, but joyfully recalls what was...

These are immortal blessings, observes Epicurus, not because we do not die but because death cannot nullify what we have lived; lived fleetingly but definitively."
André Comte-Sponville, A Small Treatise on the Great Virtues, 1996


Dear 2010,
You've been good to me.
Farewell...but not Goodbye,
Mike

Saturday, December 18, 2010

RAC Winter Contest


I used my one-transistor, 80m, Reggie transceiver to make fifteen contacts in the RAC Winter Contest last evening. I operated for just over two hours with an RF output power of 57mW and no receiver gain

Minnesota's WA0MHJ (1613km) was my best DX of the night, followed by N4DW operating from Tennessee (1168km) and VE1OP in Nova Scotia (1007km). 

This evening I worked fourteen Canadian stations in the RAC Contest. A newly recharged battery pushed my RF output power up to 80mW. The best DX tonight was VO2RAC/VO2NS in Newfoundland (1074km), VE1AYY in Nova Scotia (759km) and VY2RAC/VY2LI on Prince Edward Island (741km).

I made 29 contacts (one duplicate) in total; working six provinces (ON, QC, NS, NB, NL, PE) and four of the fourteen "RAC" stations.  

Minimalism and QRPp fun aside, I enjoyed taking part in the RAC Winter Contest using a radio named in honor of the great, Canadian radio pioneer, Reginald Fessenden.

My thanks to all!

73,
Mike, AA1TJ

Tuesday, December 14, 2010

JH1FCZ: Fancy, Crazy, Zippy

Victoria and I hiked to the top of Camel's Hump this past October. A few days later I sent our friends several of the photos that we had taken there.

Nearly two months later a message arrived from my pal, JH1FCZ. Attached to his message I found one of his recent watercolors. Tadashi had used one of our photographs as the model for this painting!

Here is the photo that Victoria took on Camel's Hump


And this is what Tadashi so kindly sent me


His masterpiece will soon be framed and hung in a place of pride. I think it's absolutely beautiful. A work of art evokes emotion. Accordingly, I can't look at this and not recall the lovely Autumn day that we spent on the mountain. No less, it evokes the emotion of friendship. In fact I'm touched down to my bones. Thank you, OM.

Some of you will surely remember JH1FCZ as a co-developer of the Hentenna. Tadashi also edits a wonderful online magazine, CirQ; the back issues of which may be downloaded here

Issue 16 (click-on the magazine cover to download) is an example of the types of interesting projects that can be found in CirQ. A simple, 6m AM QRPp transmitter design appears on page 6. One doesn't need to read Japanese to figure this one out. 

But what's going on on page 10? Evidently, Japanese QRP operations are not limited to RF. In fact, these fellows are working DX with a pair of plastic cups and a 300m length of string! In the other issues you'll find details on how to rig a cup and string "party-line," and even a proposal for working around corners!

In Issue 18 the transmitter from Issue 16 is combined with an equally simple superheterodyne receiver. The result is a miniature "milliwatt" station suited for "mountain-topping." The photo on page 7 shows an intrepid climber standing above the clouds with  his radio plumbed into a Hentenna. The map on page 6 indicates the AM stations that were worked with this tiny, QRPp rig.       

             

Friday, December 10, 2010

Solidarity -10dB

I've had 21 QSO's with Solidarity thus far. The only DX station worked so far is FG8AR, although W7CNL (Boise, Idaho) is actually located 100km further away. In fact, Jack has reported hearing my signal most everyday of the past week. On one occasion he copied my signal at 569.

On 12/9/10 I connected a step-attenuator in-line with the antenna. On the very same day K8KJ (at 1103km) briefly copied my signal with 10dB of attenuation switched-in (4mW); pretty neat considering the poor band conditions!

Dave, AB9CA, operating near Mobile, Alabama, was kind enough to send me a recording of my signal yesterday. Please click here to listen to my 40mW signal as received at a distance of 1993km. My signal is fairly weak at the beginning but rises considerably by the middle of this recording.

On December 15, I received an email message from DL3PB. Peter noticed that one of my CQ's had been logged by K4TD's automated receiver with a signal-to-noise ratio of 40dB...again, this is with 40mW feeding an end-fed wire over a 1572km path!

   

The lowest powered station that I have copied so far is K9IS (1258km) using his RockMite at 350mW. Today I worked W4DNE (1379km) while he was running 5w to an attic dipole. That QSO was followed by a contact with N9CX (948km) running 1w from Ohio. Here's a scan of the log as of today. My first contact with Solidarity was with KE4YHY on 11/26/10.

On 12/14/10 I worked W7CNL again. This time Jack was running his Ten-Tec R4020 portable transceiver with an RF output of 4w. He was 569 here on peaks.  



Tuesday, December 7, 2010

Solidarity Today


Despite continued poor 20m band conditions I had a wonderful time today with Solidarity

Minutes after turning on the rig this morning, I heard WA0ITP/QRP from Iowa (1645km) calling me right "on-sked." We had a short but nice QSO with 559/339 reports. Thanks again, Terry!

Shortly afterwards, W7CNL replied to my CQ; giving me my best DX of the day (3658km). Jack was running a Corsair at 90w from nearly across the continent. He wrote a follow-up email in which he reported hearing Solidarity's 40mW signal several times last week.

I next had a short QSO with K4FH (1466km) in Buford, GA with 569/339 reports. In a follow-up email Chris says he worked me on his indoor attic loop antenna. Wow! 

My fourth QSO was with W8FS (888km) with 579/339 reports. He was running a Kachina at 70w into a TA33 Yagi.

The fifth contact was with with the well-known Arkansas QRPer, WA5BDU (1992km). The reports were 449 reports both way. Nick was running his Elecraft K3 at 5w into a tribander Yagi.

Number six, was WA8REI (914km) with 559/529 reports. Ken was running 5w to a Hustler vertical. Ken sent, "40MW IS THE LOWEST PWR I HVE EVER WRKD." I'm always happy to hear that!

W4FOA (1486km) answered my call for QSO number seven, and an incredible 579/579 exchange! Tony remembered me from our voice-powered New England Code Talker QSO last year. Today he sent, "FB MIKE SOLID ARMCHAIR CPI."

My 8th and final QSO of the day was with WA9ETW (1362km) with 559/529 reports.

All but the first QSO was made by calling CQ, although WA0ITP and W4FOA were kind enough to SPOT me. Calling CQ is probably the most difficult way to garner a QRPp contact, but with a rock-bound transmitter there's little else to do but cross your fingers and begin "bleating!"

Again, the conditions were generally poor again today with most everyone complaining about the high QRN. Peter, DL3PB, reported the signals coming across from North America today on 20m were rather anemic. Indeed, the only DX station that I heard was a weak ZS2 station from South Africa. Taking this into account I'm just shy of ecstatic over my results today with 40mW and three pencil tubes. Thanks fellas! 


Speaking of pencil tubes, I came across an interesting passage the other day on the history of Raytheon subminiature tubes; such as the one used in Solidarity's transmitter.

"Prior to the war he [Percy L. Spencer] had experimented with developing subminiature tubes so that he could make a radio-controlled airplane model for his sons. These tubes ended up playing a crucial role in the development of a proximity fuse detonator..." Raytheon Company: The First Sixty Years; Earls and Edwards

The development of the proximity fuse tube was anything but a one-man, or even a one-company effort (the engineers at Sylvania Electric, among others, made important contributions) Still, I hadn't realized the degree to which Percy Spencer was involved in this project. 

Raised a poor Maine farm boy; lacking even a diploma from grammar school, Percy went on to become an innovative inventor and a leading designer of vacuum tubes.  As one MIT physicist reputedly quipped, "...he could make a working tube out of a sardine can." 

http://www.softslide.com/volumes/v2/t3/history/readers_digest.htm
http://www.softslide.com/volumes/v2/t3/history/globe_gramps.htm

Please click here to download the twelve-page, Raytheon Commercial and Military Subminiature Tube Catalog for 1961.

Writing from the Baykonur Space Port, Alexander, UA9LAK/UN7 (aka UA3VMC) kindly reports

"These tubes using rod electrodes were designed for use in particularly harsh environments. They were used in military equipment (and according to some, even in on-board satellite equipment, etc.)

I also have a surplus emergency  radio - of the kind used by stranded airmen and sailors - that uses tubes of this type. These tubes were also used in mobile VHF and HF radios."


On Alexander's website I found this lovely QRP Verse

...И поэтому ручку настройки
Я вращаю на ту частоту,
Где такие, как я, собираются
Чтобы сделать доступней мечту.

Вот сидит под своею антенной
Мой пока незнакомый собрат,
У которого "мелкий" трансивер
И в антенне все те же пять ватт.

Побеседуем, если удастся
Злых помех нам толпу победить,
Попрощаемя и "разбежимся"
Вновь к ДХ-ам дорожки тропить.

....Пожелать остается терпенья
Тем, кто сможет в нелегкой борьбе
До ДХ-а в толпе "достучаться"
И сказать гордо: "Я - QRP!"

There beneath his antenna 
Sits my brother still unknown
And his small transceiver
The same QRP as mine

Friday, December 3, 2010

Solidarity

The receiver used in Solidarity is an upgrade of that used in my November 27, 2010  station. The detector now operates in the vicinity of 2.87MHz with improved frequency stability. Furthermore, the addition of the frequency-converter stage introduces isolation between the detector and the antenna.

My earlier receiver was also plagued by microphonics. While a vibration damping mount for the CK5875 detector tube would have greatly reduced the problem, I decided to side-step the issue entirely by switching to a remarkable, Soviet-made, subminiature pentode.


The 1Ж24Б (1J24B, 1SH24B) is a marvel of ingenuity dating from the 1950's. Examining the close-up photos on this German site, one might be tempted to exclaim, "Where are the grids?" In fact, three grids are present, only, they aren't helically-wound, neither are they ladder or screen structures; they're collinear! This device is the product of some clever electron optics (see post #7) involving tiny sheet beams.


Another virtue of this tube is its extraordinary emission efficiency; a definite plus given my eventual goal of building a minimalist's vacuum tube-based portable QRPp station. 

Details of the 1Ж24Б are covered in this 1962 Soviet vacuum tube manual. An article on the topic of these tubes appeared in the July 1960 edition of the journal, "Радио." Please click here to download this magazine issue. The article begins on page 34 (page 40 of the scanned document). 


Aside from the vague speculation they may have been been used in the MIG-25 (Foxbat), it's clear these tubes were used for portable military equipment of the Warsaw Pact nations; an example of which may be found here. They were used for similar applications, and during the same time-period as the likes of my Raytheon subminiature tube was used in NATO equipment. 

I rather like the idea of melding the CK5875 and 1Ж24Б - these former Cold War adversaries - into a single radio.  



The 40mW transmitter amounts to a simple, crystal-controlled, Miller oscillator followed by a high-pass, L-network for impedance matching. For maximum efficiency L1 needs to be a Hi-Q inductor. 

The regenerodyne receiver IF tunes from 2.877 to 2.807MHz in order to provide 20m coverage from 14.000 to 14.070MHz. L2 and C4 constitute a 16.877MHz trap filter. Adjust L2 for maximum 16.877MHz energy at the filament. VC2 cancels the residual trap reactance at 14MHz. On paper it improves the sensitivity by 4dB; it's not strictly necessary. While tuning across the band VC3 needs to be re-peaked every 10kHz or so. VC4 is the main-tuning variable capacitor. VR1 is the regeneration control. 

The CK5875 filament draws 100mW at 1.2Vdc and the 1J24b's each draw 15mA. Altogether, the receiver only consumes 217mW of input power. Not a peep of SWBCI has been heard on this receiver in several weeks of operation.



Despite poor band conditions, last week Solidarity provided me with several pleasant QSOs. On Thursday, K9IS replied to my CQ with his Elecraft K1 from Wisconsin. Steve was running 3w to a dipole. He was 579 on the regenerodyne and he gave my 40mW signal a 339 report. 

An hour later N4KGL/4 answered my call. Greg was operating his little, Wilderness SST @ 3w into a Hamstick dipole that he mounted atop a 20' mast. Greg was on his lunch hour and operating from the parking lot adjacent to his office. Details of his setup may be found here, here and here. Greg wrote later

"I had good copy at the beginning for the essentials and then fading in and out....When I turned on the rig I was hearing nothing in the SST's 8 khz receive window. So you were the first signal that I heard."

Working a guy standing in a parking lot on his lunch hour (a stone's throw from the Gulf of Mexico) with 40mW and some vintage pencil tubes stuck in a plastic protoboard here in snowy Vermont is just plain cool! 

A few minutes after I signed I heard K9IS calling me again. He'd heard Greg's and my QSO. In fact, he'd continued to copy my CQs on a variety of rigs ever since our contact. He said that my signal had peaked briefly at 559. The most exciting news was that despite a slight frequency offset in our crystals, he'd copied me on his RockMite. Steve then switched to the RockMite (at 350mW) for the remainder of our contact! I gave him a 559 (an easy copy here aside from the QSB fades). He copied me at 329. Just amazing...

These great QSO's were the "shot in the arm" I needed to go on calling, even as the band conditions appeared to further deteriorate. Tuning around, I only heard a couple of signals on the band now; besides it was nearly sundown. But you know how it is...just a couple more calls  :o)

And suddenly, big as life, I hear FG8AR calling me! I quickly send off a 599 report; feeling my pulse all the way to my sending wrist. FG8AR replies with a 539 report. He says his name is Olivier and asks, "PSE UR PWR?"  I reply, and he responds, "GUD GUD WITH 40MW." 

It took me a moment to recover after we'd signed; I kept looking at the tiny CK5875 envelope while trying to visualize the geographical location of the island of Guadeloupe. 

Most exciting of all is the thought of what will be possible with Solidarity when the conditions on 20m are actually good! 

So thanks for your interest, guys. I hope to be QRV on 14.060MHz with this rig come next Tuesday (12/7/10). I hope to hear from you!

       

Links

http://www.hi-ho.ne.jp/ux-45/russian.html
http://www.radiolamp.ru/shem/tuner/3.php?no=31