May 26, 2014

Summertime Memories: 2013

HAMRADIO 2013 Friedrichshafen

Our summer holidays usually start at visiting European largest HAMRADIO fair at Friedrichshafen (DL). In 2013 things were no different; we hired 3 rooms for two nights in a nearby small village and enjoyed 2.5 days visiting the HAM-fair, eating &enjoying the view at lake Constance and as a highlight, visiting the saturday-night Bavarian Contest Club dinner.

As this was our umpteenth visit at the fair, only few items were bought. One tends to get overloaded with stuff back at home, so our priorities have shifted. Meeting many old but also new friends, has become a major fun part.






A first meeting was planned for some time with Romeo S59M(ex-S52RU) who was organizing the successful IG9Y MM operation for CQWW-SSB. From left to right: Romeo(S59M), Aurelio(PC5A), Me (PA5MW), Rens(PA3FGA) and his YL Claudia (PD5AX). Note the carton box behind them, which contains our new Flexa field-day 144MHz antenna. 
Our car already carried some HF equipment and transverters for 6m and 2m, we just needed an antenna to go with that.



 



Special aluminium polish on the radiator and 1st director add some valubale extra dB's...






On sunday afternoon we left for Malbun/Liechtenstein.



Antenna setup near cabin in Malbun (HB0)

There was no ham-radio activity planned that year. None at all as below picture verifies.
But just for dealing with known RF addiction, we did put up a multi-band 10-15-20m cats-whisker dipole @8m and a HB9CV for 6m at the top at 10m AGL/ 1670m ASL.






The dipole of a 10m yagi also carried the wires for 15 and 20m. Some ex-mil fiberglass poles on the right held the 2m/70cm vertical, used for local chat and to track our SOTA trips via APRS. At 2m height it carried the new bling Flexa Yagi.


Traditionally at the first evening, the main diner table in our cabin was transformed into a shack for 3 operators. Both my Elecraft XV50 and XV144 transverters were installed and connected to a K2. The power supply was my Diamond DMV330, but the one without Earth wiring. So after switching on and playing with some coax pigtails, the preamp of the 6m transverter was defect. And the K2 cabinet felt tingling. What a rookie-error, quickly established some proper earth connections



During the evening I had a CW contact with a G4 on 144Mhz! But he disappeared in the noise. As this was not some kind of guess-calculate-noise-intervals-mode but a 'pure humanoid operation', there was no completed QSO this time;). Nonetheless it did offer pure excitement. But Murphy decided to play along; after another half an hour the transverter started showing a life on its own. It would start to clatter indefinitely after any >10sec transmit period. Whatever we tried, it would not go away. Surely this never occurred at home. Next to that, all units had been intensively tested before departure. No TX on 2m anymore and no 6m at all.  Time to go..

Into the mountains

On a Saturday we visited the not-so-easy-to arrive top of the "Gorfion" to activate a SOTA FIRST (OE/VB-241). After the available Geocache was also found we went down along the trail of the Augstenberg. There we spotted a nice possible location to setup our new bling 144 yagi. 
Next morning we returned to that spot, setting up the 7el/144 and connected a TR751 to a pack of LiFePo4 power-batteries (2x2500mA=330g). The Kenwood was also taken from the Hamradio flea market and in mint & 'working' condition.


Setup-crew arranging deep-fringe HD antenna. 
Armstrong rotor.

IARU VHF July contest

The almost flat terrain at 2300m ASL, was already nicely warmed up by the afternoon sun.
What a crowded 2m band, not a single free spot to find!
I started CQ'ing around noon on 144.198 and quickly enjoyed a nice pileup.
After some 30 minutes, during a DL QSO, I noticed  someone was calling me in CW from The Netherlands ! How cool is that? Quickly  I gave PA3CWN an RST report and consecutive QSO number. Now that's a nice troposcatter QSO.  And copiable by ear ;)
My band openings, besides QRO stations within 200km, were relatively short and produced serious QSB from my side, so I was told. Turning the antenna into other directions delivered new ones from those areas every time.



But a rainstorm was slowly arriving, restricting our mountain visit to few hours only. My voice welcomed the departure as I had to talk loud and articulate heavily in order to get a few lousy Watts out of this Vintage Kenwood :)

In the end I made 44 QSO's to HB0/HB9/F/DL/PA/I/OE/OK/OL, not bad at all!
Into Holland I also worked PA0PVW, PA3PCV, PA1AT and PA2CHR (ODX 764km).

Many thanks to my crew for carrying some of my stuff and 'setting up the VHF site'.

 

What a superb way to enjoy a few hours in a VHF contest !


p.s. I just got reminded I was served a fresh cappuccino during the contest. Probably being to focused on the contest itself, I really cannot remember that at all....? Anyway thanks for that!

Feb 7, 2013

WSA 160m (1)

WSA160m, choosing a headphone

Weak Signal Audio 160m, a new project

When searching for progression, sometimes there is a need to look at matters from a totally different perspective.
In our efforts to dig deeper in the band-noise, opening up another layer, making new CW QSO’s possible, we decided to do a different investigation and perform some tests. This project does not touch on antennas or any RF/IF hardware. Instead, those steps from the detector to the 'decoding by human brain'. From your AF stage, via any transducer, passing ear-wax to that final conversion into gray matter signals.

Why discuss the use of headphones?

There's several potential topics to be discussed along this extended audio path. At some point we need to look at headphones, and perhaps pick one or more relevant types who might serve during future tests. Questions arise; are there relevant differences in headphones when it comes to making that extra QSO? What other parameters exist next to the obvious ‘wearing comfort’? Is there a single winning model or do you individually need to test-find a match for the operator?

List of headphones under test

No effort was made to add any specific commercial popular model or brand. We just grabbed as many HAM-Radio, Hi-Fi, DJ, Advanced Gaming and/or your typical MP3 headphones as we could get. All full-range stereo models. Some equipped with in-line volume control(s).

Medium sized “on-ear” models:     Philips, Sony
Large sized, fully ear-surrounding models:    Heil, MFJ, Beyerdynamic, David Clark, Philips
Small sized “in-ear” models:    Koss, Sony, Philips

We started with more than 20 models, slowly narrowing it down to about a handfull which offered small advantages in sudden areas.


Just a small bunch of the tested headphones

Comparison test conditions

The sound source was 160m recordings from CQWW-CW- 2012, using the Microtelecom Perseus. Filter taps were set to 32, as this enhances weak signal detection and avoids typical digital harshness which is common on some DSP's . During the first weeks the internal sound card of the laptop was tried, evolving to external DAC units, different external (Hi-Fi) amplifiers, finally settling for the premium quality Objective 2 Headphone amplifier. The O2 is an open source amplifier designed by NwAvGuy, with emphasis on benchmark performance and low cost.
http://www.jdslabs.com/item.php?fetchitem=o2full Later we also added the O2 USB DAC combo version. 
You can write a separate document on the required amplifier performance and correct matching to any type of headphone. Read more at: http://nwavguy.blogspot.nl/2011/07/o2-headphone-amp.html 

The Objective 2 headphone Amplifier

The listening test

From Early December till mid-January we spent two evenings per week listening to many different, but carefully selected time segments of the contest recordings, offering:
  1. Weak signal alone in the band noise
Extreme weak signals in/out of the band noise being extremely difficult to read, let alone decode for a valid QSO. Sometimes under lots of QRN and/or slow QSB. Listening for a longer duration to any CQ’ing station being called by far-far-away-dx. Sometimes we would eaves-drop on a CQ-√≠ng big-gun, switching his 4SQ 180 deg. back and forth.
  1. Weak signal close to a loud signal
This is also a dynamic range test; how does it (and your hearing) deal with weak signals in an environment of the complexity of loud sounds and quick volume changes.


Our main goal was to distinguish between:
  • How easy/difficult is it to pick and decode a weak CW signal?
  • Which is offering you a better reading resolution while tuning the band?
  • What other audible effects, good or bad are noticed?

It was not about the offered sound quality as such. This was about making an extra QSO Y/N, next to being able to listen over prolonged periods of time, either comfortably scanning the band or monitoring QSO after QSO of some running Big-Gun.
Surely we were subject to the typical learning/recognition process when repeating sound clips, listening level differences and the inevitable ‘sound memory effect’ when doing endless A/B/X comparisons. But along the way several headphone models started to show their merits in one or more areas. This was not about doing a headphone shootout, but achieving our goal by learning from all aspects.

Noise cancellation headphones

A few years ago we did several tests, using different in-/on-/around-ear active&passive NC models, both at home and our club station PI4TUE. During 48hrs contests with many operators available, we received a lot of feedback. At best the NC models would offer some cancellation of the high environmental noise at low frequencies. Rumble and fan-noise from > 20 network servers in the contest room was attenuated to some extent and did offer some relief. But the active models showed other nasty side effects like additional internal amp noise, sound distortion and dynamic range issues. The passive versions, with ear surrounding gel-pads on the other hand, performed outstanding. Today, 3 operators still use these at home and in contests. Only the passive noise cancellation gel-pad version headphones have been used in this test.

Test results

High sensitivity HP reveals internal AF amplifier noise &hum
Every hum, noise, pitched distortions (audio birdies) of the AF amplifier are being heard. And this effect becomes much worse going to premium and high-end range models. The more expensive the headphone the higher sensitivity they usually offer. You need a fairly loud source input volume to overcome this amplifier QRN. 
 
AF amp internal noise/hum level must be very low
That is why we quickly went to search for the best available headphone amplification ham operator budget can afford. You can build your own low-noise headphone (distribution) amp, but don’t take it too far; read the chapter at ‘Designer Components’   From my past years at service and design of consumer audio Hi-Fi equipment, I recognize these statements all too well.
At future test we will show AF spectrum outputs of various HF transceivers.

Presence of AF background noise affects the ability to distinguish weak signals
We are subject to back ground noise in daily life and have become used to it. The fixed level of AF amplifier noise in the background creates an unconscious distraction. This became very apparent when using the in-line volume controls; making them less sensitive effectively pushed the AF noise level below the hearing threshold. You only recognize this benefit when you free yourself from the distracting noise. However, now offering much higher impedance to your amps output might affect its performance in other areas. Again a reason to switch to a quiet amplifier, also capable of handling a wide impedance range.

Lower range of audio spectrum HP allows for disturbance, like rumble or typical key click thumbs
Again, premium headphones reveal them pretty loud. Today, many on- and in-ear models are ‘tuned for extra bass’. Next to your CW passband filter settings, additional high pass filtering is a possible solution. But not used during this test.

Upper range of audio spectrum HP does not contribute to readability
Obvious and confirmed while using some experimental settings of filtering, sound equalization etc. A dedicated lowpass filter is under design, but never used in this test.

Open system on HP allow for distraction of environmental noise, decreasing focus over time
No problem if your shack is a remote, dead quiet man’s cave. Whatever your preference, you need at least some closed ear-protection, so you can concentrate on the job. We find open systems only usable for what they are intended for; playing music.

Premium High Fidelity HP offer an aggressive time envelope on noise/impulses/key-clicks or any radio communication sound. This is much fatiguing.
Whatever the great detailed sound and high dynamics offered by the premium to high-end quality headphones, they have a serious downside. They closely follow every quick rising signal and reproduce a ‘truth’ which becomes quickly annoying. Interesting during the first minute, but soon becoming unpleasant for your hearing. It’s like listening with AGC OFF, times 100. Even clear band noise slowly becomes fatiguing for your hearing. Let alone any nearby key-clicks, pops etc. For those using any antenna pre-amplification, be warned; it’s like sticking a needle in your ear every time the neighbor flicks a light switch. The overall result is a rough, harsh sound experience. Despite the much more detailed sound, there was never an advantage while trying to detect/decode CW weak signals.

Communication drivers/cheaper HP models seem to have a limited rise-time, thus masking the aggressive time envelope noise/impulse effect
For recognizing and decoding weak CW signals, the low-end or cheaper models performed equally well, less the harsh and quickly fatiguing sound experience. A cheap hamradio boom-mic headset was preferred over its premium competitor. I recall that exact same experience when I bought the high-end model after having used the former for several years. But the larger, much more comfortable ear pads and sturdy mic-boom did make a valid difference. I only use it when making a phone QSO on 50MHz.
Mind you; the time envelope of CW signals is relatively slow. And their sound environment (band noise, off-pitched CW signals)is such different, that we do not need any additional sound resolution to distinguish them better.
Premium headphone models just offer too much; less seems better.

Communication drivers/cheaper HP models seem to have a mechanical threshold. This can offer less detail at very low listening volume, perhaps also masking weak signals by amplifier noise
Although we were splitting hairs, a few low end models showed this effect. It became more apparent while using noisy amplifiers and/or connected to some of our HF rigs. Turning up the volume cleared the effect.

Louder is NOT better
Turning up the volume for completing that difficult QSO is not enhancing your hearing ability.
On the contrary: your hearing ‘Auditory Filter’, which allows for max distinction of isolated signals, is negatively affected: http://en.wikipedia.org/wiki/Critical_band Read more about your hearing at: http://projekter.aau.dk/projekter/files/9897666/Auditory_filters_at_low_frequencies_07gr1062.pdf 


Interesting remark: “another important effect of loudness perception is that not every sound that is above your threshold of hearing can be heard. If a sound is given, while a near louder one is also present (within the auditory filter) then it is possible you do not perceive the lower one. This process seems intuitive, but on the psychoacoustic and cognitive levels it becomes very complex. The term for this process is masking.” In short: your hearing ability has a minimal bandwidth and a varying curve.
MP3 encoding uses this masking effect of human hearing to lower the data rate, without affecting the overall ‘sound quality perception’.
Be cautious about treating your hair cells. You want your personal auditory filter curve sharp and symmetrical. Preserve your hearing!
The above shows a typical hearing of a young, healthy person. Now see what has happened to those suffering from hearing impairment:
Guess how you are going to compensate for that lack of hearing ability
Right; you will turn up the volume even more....
 
And exposure to loud listening volume slowly might activate your ‘Acoustic Reflex’, the attenuation reflex in your middle ear. And again you compensate by reaching to that volume knob.
Although turning up your listening volume seems effective sometimes, it certainly has more to do with your current focus and perhaps the continuous distraction from environmental noise.

Closed HP systems with passive noise cancellation allow for high focus at an average lower listening volume. Separation of weak signals is easier at lower audio levels here.
The ear surrounding gel pads model from the professional aviation headsets offer clear, isolated reception of weak signals in noisy environments. They avoid listening fatigue in lengthy contests. The gel pad aviation model was friendly for the ears, even after many hours of contest use. But one of our clubstation operators perceived the ‘ear sealing effect’ as uncomfortable. Another instead, uses a generic hearing protector around his in-ear headphone, like drummers do in their studio.

And some final remarks


'Clean' TX signals, with less sidebands/key-clicks, resulting at AF level in more approaching a true sinus character, are easier to decode as a weak signal
Sound timbre and tonal coloring are a matter of personal choice, as is wearing comfort
Passive/active sound moderation like limiting and/or low-pass filtering may have a pronounced effect, but are to be proven as we have not used these in this test.

Rens, PA3FGA
Mark, PA5MW






Feb 29, 2012

Beverage On Ground (BOG)

Lowbanders cannot operate without the availability of a dedicated receiving antenna. One that does suppress local noise, suppress sky noise from certain directions and suppress QRM from certain directions. In fact, all it does is deleting signals and/or band noise you do not want. What remains is the dx, coming from that single direction that was left unattended. That is really it. 

The ability, to delete all directions but one, is put in two figures of merit; MDF and RDF(refer ON4UN’s book). In short, a kind of horsepower if you will, to distinguish the good from the better receiving antennas. And just because humanoids simply must quantify everything


I refuse to go in detail about RDF and MDF, because they represent computer models from antenna modeling programs, which by principle, cannot handle close to ground antennas, or more specifically, cannot handle real ground at all. Until someone takes a helicopter and runs zillions of circles at different heights around a lowband receiving antenna, measuring its pattern, I rather use my ears instead. 

And then again; what elevation angle is required at which moment? Too many parameters. Better have a few antennas more at your hand!

Setting up station @PI4TUE




The lowband receiving antenna is a whole lot different from multi-element VHF yagis, where forward gain is simply the most important figure of merit.
But, there is also a common factor between them; the “better” the antenna, the smaller the forward lobe in degrees azimuth/elevation. Where “better” has a total different interpretation; the VHF yagi needs the small lobe to collect all tiny weak signal particles from the dx and to a lesser extent, avoid signals from the side and rear. Lowband receiving antennas mainly concentrate on deleting signals from all unwanted directions and to a lesser extent collect the weak signal from that direction which remains.


Antenna computer models?


I shit on virtual, calculated dB’s.

In the end it all boils down to achieve a S/N ratio where you can make the QSO yes or no.



There’s no free lunch.
A decent lowband receiving antenna (like multi phase staggered beverages) requires real estate and/or extensive hardware and trimming (6-9 Circle). A physical shortcut like Flag/Pennants/K9AY/EWE, or even the BOG is a choice mainly based on the will to put up any RX antenna to receive at least something. Some work better than others, depending on the environment. And then there is man made noise for which vertical polarized antennas seem more sensitive. Or is it not?

 
You need to experiment and find what works best for you.

On a site note; even a short vertical, suppresses high angle signals thanks to its theoretical doughnut shaped pattern And being less susceptible to local noise because of its short length, this IS a valid dx receiving antenna. The total opposite is a short backyard NVIS covering high angles only. Here you have it; two RX antennas which fit even the smallest gardens!

 
Need proof? Find my result in 2012 CQ160 CW Low Power




ARRL DX CW contest 2012 @ PI4TUE club station
During last week’s ARRL DX CW contest weekend at our PI4TUE club-station, we (again) were in desperate need of a working RX antenna and had little time to install it in the usual public space.
The PI4TUE station is located in a building at the Eindhoven University of Technology.
It’s nice to have antennas at 70m above street level, but the local noise level is very high. Let me emphasize that again; for the lowbands extremely high!
Both on the roof and on ground level (up to a distance of 150m from the buildings), we have experimented for some 10 years with the following receiving antennas: K9AY, KAZ Delta RX(only on roof), magnetic loop (s), short tuned verticals ... etc. All including extensive common mode filtering. 


Nothing ever offered any S/N advantage compared to the available TX antennas; full size 40m dipole and vertical @65m, full wave 80m loop @73m and two full size 160m 0.25 slopers @63m.
Because of limited available real estate, beverages have not been tried thus far. Also, there are some large rusted fences along the property perimeters.


But Topbanders never give up. So this year it was time to try a BOG.


Do or do not, there is no try!
On a piece of lawn, facing the USA, 8 plastic fence posts were put in the grass. A 70mtr (max available space) long 0.5mm dia insulated stranded copper wire was linked on the bottom of the posts. At both sides a copper pipe was hammered 1 m deep into the ground, hoping NOT to meet any local wiring. KFC! From our shack at the 13th floor, 150m 75Ohm SAT coax + another 50m RG58, across several roofs, cross-overs between buildings (which required informing security, asking them NOT to shoot us from the roof) was used to connect to our BOG through a 1:4 transformer on a BN73-202 binocular. There were no 50/75 transformers installed. This was never tried before, not permanent and we had about 3 hours available.


On average, the antenna wire was at a height of 3 to 12 cm across the lawn.


Why not directly on the ground? Well, according to theory, directly on the ground should have an electrical "lengthening" effect (which is wanted). But on higher bands (40m) such can introduce a direction reversing effect (not wanted). Also, flat on the ground the signal is supposed to drop several dozen of dB’s. Well, theory is one thing, and often ensures that we hopelessly remain staring at computer models. 


Instead of debating, better start building the darn thing!

Since we really needed *any working* receiving antenna on 160/80/40 and there was no time for experimenting anyhow, the wire was deliberately hung 2 inches directly above the ground.
Termination at start was 390 ohms, and later changed to 195 until the analyzer measured a flat SWR curve up to 10 MHz.

At the TRX end a HD version common mode filter was connected: 17 turns of RG174 on a #77 ring core, followed by a galvanic separation using 2x2 turns on two BN73-202 binoculars, with the secondary separately routed in Teflon tubes. Over the top? Yes, maybe, but since all our previous effort only offered noise and I use this kind of filter successfully at home. 

On Friday afternoon, around 17UTC a quick check at BCB frequencies well known to us (1584, 4015, 6995 etc) all clearly showed F/B and F/S performance, which was promising!

"You sure you don't hit anything ??"











Blue wire near ground IS our BOG




















It works!
Those of you who participated, know this was a weekend with some of the worst lowband condx for years. Even more reason to have any decent RX antenna available.
In the contest, our antenna was a success!

None of the 20 worked USA mults on 160m, delivered by the BOG, could be heard on the full size TX sloper antenna. On 80m this was the best receiving antenna ever. From a quiet S1 background noise, stations appeared out of nowhere with S1 - S5. Again, most of them were no QSO or just not there on the TX full wave 80m horizontal loop @73mtr AGL.  On 40m about 30% was better than the quarter wave TX vertical at 65m height. In most cases the S/N was better not only because of the lack of constant cracking noise from the TX vertical.

Why did we succeed this time? Because the BOG is only active in the horizontal plane, the local man made noise is perhaps largely ignored? That is supposed to be a myth. So I rather stick to the remaining fact that on a specific lawn on which several other types of RX antennas have been tried, this one did work FB.

We do have experience with different kinds of 200-300m phase staggered Beverage antennas on (large) outdoor terrain for many years. Any kind of BOG is a poor performer in comparison.
But this thing sure has potential at (small) residential areas.


What is next?
No hallelujah yet. We will soon make some additional attempts out on the free field, before moving it along the property of our neighbors.

The internet offers very little data on the BOG.
Please, can any of you share their experience on balancing BOG parameters like height, termination, length, etc.?

73 Mark, PA5MW (PI4TUE)

Mar 11, 2011

ANY antenna beats NO antenna

Stop modeling and get on the air; NOW.
After having moved, a couple of years ago, I wanted to launch my 160m activities at this new QTH. But the list of opportunities was quickly overtaken by the local challenges. The few attempts were marred either by public exposure (neighbors included), safety issues (see nov 1 2009)and lack of real estate. Next, work and other activities shifted priorities such that I kept stuck at the stage of computer aided antenna modeling.
I had to lower my ambitions as advancing plans to the next season again and again, did not get me anywhere and certainly not the pleasure of simply making QSO's on Topband.

The stealth Topband Antenna
An unobtrusive wire up in the air as high as possible, plus a few radials on the ground resembling some sort of basic Groundplane Antenna are my major goals.
I already tried getting different wires up a large tree, but the launching velocity power of my legal sling shot wasn't sufficient.
A friend offered help by supplying a special tinned copper wire having teflon isolation. At only 0.2mm diameter this stuff is both unobtrusive and extremely light.
With help of the slingshot it is quickly launched in a large tree using a 40g weight at the end.



It's the white wire, routed along branches of a small dead tree in the back garden. The horizontal wire is a short wideband horizontal antenna.
From here it goes upwards to a large tree some 15m away, ending at a height of >22m and then some length horizontal tangled up in the branches. In total I guess, about 26mtrs. Unimportant really, since there are plenty of opportunities to match it on 160m.




A copper ground rod and some 6 attached radials varying from 6 to 9mtr (20-30ft) in length are covering the west-to-northwest quadrant. Minor detail; since the vertical wire rises up in the southeast direction, none of these few radials cover the area under this sloped GP.
The white box is a True Balance type
remote controlled ATU, which was not used for 7 years already. Together with some common mode supressor #31 FT240 ferrite core and already available coax from earlier experiments, I'm connected.




The final picture already shows the current situation where I have added another 10 radials in this small quadrant. The Yagi is my next priority for the summers Es season on 6m. And yes, that door in the upper right does need some maintenance attention.

So how does it play, QSO-wise?
Let's summarize this: a lossy 0.2mm dia wire, an even less-than-poor man's RF ground, a quick&dirty matching unit and 100W input power for that 'Sloped 160m GP'. Good points: it's at least 1/8 wave up and free in the air.
Within the hour I work stations on Topband within a 2000 km range including an UA2, but some later an Asian UA9.
The next morning at 05:54 UTC I work Dave, W5UN. Wow! Was that perhaps a special moment of extraordinary propagation? Later that evening I meet and work another well known Magic Band operator UK9AA. Two more US stations from PA and TX are worked in the next few days. It's no magic, using only 100W this antenna exceeds my expectations.
In between I have added some 10 more radials in by tiny 8x7m backyard. It requires a different setting on the remote ATU.
Using my short RX vertical I can hear many of the active dx'ers and dx-peditions on 160m. Most have large pile ups and are gone before I can make the contact. That is fully acceptable; this must not be too easy right?
New continents are entered in my log soon; JA7NI and today FM5CD. Both take some time before they are able to dig out my puny Little Pistol signal. Slow speed and perseverance while riding the QSB waves proves successfully.
Now how cool is this ???

What's next?
In the next weeks I will try to arrange:
  • Replace the ATU for a Low loss matching unit using a Heavy Duty Coil
  • Detune the TX antenna to lower (induced noise) coupling to my RX antennas
  • Add a PTT controlled RX antenna sequencing
  • Make more QSO's, have fun operating Topband


Sep 19, 2010

Back to Analog Basics

Recognize this?
Your current digital product, appliance or service is offering you daily problems. You're fighting your way through settings via zillions of sub-sub-menus, hoping to get that one simple task done. In fact your 'life-style experience' thingy is a product of guaranteed instant stress.

Now there are always some geeks nearby, offering 'help' by friendly telling: you are doing it all wrong. Your settings are incorrect and additionally need to be tweaked(by principal), upgrades installed and special geek-tricks added to the equation before such a device can work at all... This takes time. Yes a lot of precious time (hours), during which you're told how you are living your life utterly wrong, explained at the same geek tech level, which slows down your present perception of (lost) time even more.

And then it shows; the offered intervention did not help.

Surprisingly this does not change the mood of your geek-friend. Quite the opposite; you receive an even longer explanation about why it did not work. In many details that is, until you finally surrender by nodding that you understand him completely...

Why these creatures are willing to spoil so many consecutive hours of what could have been a fine day is beyond my comprehension (I already exploded mentally twice). I know the world needs them for propelling our technical development. And basically, I am a technician as well. Professionally I'm creating bridges between Planet Geek and Earth, thereby understanding both entities. But in my free time I find myself more often in the base camp of the average John Doe nowadays. Effectively I'm pulling myself away from the interventions and want to call it a day. However my friend is more focused than ever and does not let go.

More geek tricks are pulled in and, since the challenge level is rising, others step in soon, turning this into a geek frenzy. After much longer it is finally your product bursting up in flames at which the whole pack is joy-ably agreeing it is you who choose the wrong Operating System in the first place.

Well I'm sorry, but back on earth I find it an insult if one imposes such a discussion to a consumer in the year 2010. I know consumers are indeed slowly mentally degrading, but geeks lack common sense. The product is just crap, period.


Daily Digital Crap Products
Getting to my current affairs; I have been trying some 5 different types/brands Digital Cordless Telephone sets these last couple of years and concluded it's crap.
Battery charging issues, never correct battery indicator, non-responsive number buttons, blinking lights, alarm messages on the display etc...
My favorite annoyance is the "missed call" message on the display. It took 18 (!) button pushes to clear that message from the display, every-time. Why is it that manufacturers aside from implementing a hundred ridiculous options, cannot create a selectable basic simple operating mode, offering nothing but making a call?
I have installed one complete set with 4 handsets at my parents house. Their world is different and they do not recognize any of the display messages at all. And the one in their bedroom is blinking red from day one. Every time a unit does not work or responds differently, they conclude it's probably their operating error and accept that. Hmmmm...... maybe a small learning opportunity for the control freak?


Back to Analog Basics
Out goes the digital crap phone stuff, in comes the Beocom 2000 from Bang & Olufsen. I bought this telephone sometime during 1990-1995. It has an astonishing design. It's greatest asset was and still is its superb audio quality. I used this great device for over 12 years without a flaw ever...



The brown leather pouf is over 35 years old and needed a 2 hour leather creme polish as it was totally dried out. Both are milestones from the past. Guess what? They both still function well.
This model has just a few basic functions like 20 memories, a red emergency number button, an LCD showing the dialed number (no call ID recognition) and 3 selectable true analog ring-tones.
Installation process takes 1 single non-dramatic step: connecting your RJ11 cable. No batteries to install and charge 24hrs, no firmware upgrade, no operating system settings, no help desk and no on-line manual.



That long greyish thing on the left is your handset(wired connection!). As soon as you pick it up from the hook-switch you hear the analog line buzz. Not that digital created artificial sound image from the past, just the real thing.
No answering machine, mailbox, Call ID and/or hide call ID. Just the basics needed for a phone conversation between earthlings.

Feb 24, 2010

Doing it right....

ARRL DX CW Contest 20-21 feb 2010

Last weekend I participated at our club station PI4TUE.

This is the University of Technology Eindhoven's contest call.

Call: PI4TUE

Class: M/S HP

Operators: ON9CC, PC5A, PE2HD, PA5MW

Summary:
Band QSOs Mults
-------------------
160: 83 29
80: 261 42
40: 866 55
20: 999 59
15: 933 58
10:
-------------------
Total: 3142 243 Total Score = 2,290,518


Club affiliation: Bavarian Contest Club

Antennas: 160m sloper@220ft (RX: 5ft vertical@200ft), 80m full size horizontal
loop@220ft, 40m 1/4 GP @200ft, 20-10m 3el SteppIR
Rig: Ten-Tec ORION
Power: 400w from Acom 1000

Wow! This was big fun. Some of us love this contest even more than CQWW.
Finally we made some substantial progress compared to our past entries; at 1000 QSO's extra this year we have moved from the back end to the middle(ish). Watch out for us next year !


What went very well?

Preparation

This time I'm well prepared by taking a few days off before and after the contest. Being well rested and refraining from doing the *last minute job* I am fully motivated.

Looking fresh during the final hours...... :)))

Antennas
The new 3el SteppIR is a big improvement over the 15yrs old 3el compromise trapped(read: noisy) yagi. Next the 80m dipole at 220ft was replaced by a full size 80m horizontal loop at 200ft along the roof perimeter of the building (thanks to PA3DSC, PA0IB, PE2HD and PA3FGA).
But there is room for improvement for the RX antennas on 40-160m.


The HF2V mainly used for 40m

80m horizontal loop along the top perimeter. SteppIR 3el yagi. 160m sloper at the right end-corner

Rig
The ORION's user ergonomics offered its merits to all operators. Especially the setup for audio (main=both ears, sub RX =right only) and the volume knobs (toggle for audio on/off) was much appreciated for operating RUN/S&P between main and sub receiver with help of N1MM contesting software; Single Band SO2R in one box so to speak.

The station has no true SO2R capabilities. Another challenge for the future.

Second operator position....... not really.

Being focused
All operators were sharp from start till end. We strained for the best (band) strategy and our senior contest op successfully taught us additional tricks on the fly.

Operator Aurelio, PC5A looking sharp during sunday afternoon

Food, coffee, sleep, etc.
There was plenty of it all and the couches in the 'lounge' were comfortable for a quick nap.


What went not so well?

Pin 1 issues
We use some 5 pc's, various audio routing, external equipment and zillion connections for different set-ups in the shack. During the contest our headphones showed all kinds of strange varying noises, rattles and hum. The room houses another 30-40 pcs, several HF/VHF/UHF transceivers and other equipment. Definitely a challenge for the future.

Lockup/crashes
Very likely related to the above; WinKey locked up the N1MM program.

The ORION needed 4 power cycles (3 for no RX and 1 for no TX).

But
All in all a very memorable contest.
Thanks to Martin PA3DSC and Steef PA0IB for maintaining a great club station.

See you in the phone contest.
73 Mark, PA5MW

Feb 20, 2010

50 MHz Bandpass Filter from Cross Country Wireless (UK)

Why a bandpass filter for 6m?
I recently ordered this from Cross Country Wireless and received this the other day.

There is a couple of reasons in no particular order:

  • Release any front-end(pre-amp) from strong out of band signals, thereby avoiding possible IM from local FM broadcast etc.
  • Avoid total blocking of 144Mhz while transmitting on 50Mhz
Both my transceiver, transverter and/or seperate pre-amp have internal bandpass filtering. The pre-amp even has a carefully tuned sharp helical filter. But in all cases the filtering is either very wideband or only after the LNA. A seperate, dedicated 6m bandpass filter might clear things up, in theory that is.

The Cross Country Wireless offers bandpass filters for 50, 70 and 144 Mhz. They handle 100W RF power and contain a built-in lightning surge arrestor as well. High voltage spike protection too; nice !















The bandpass filter comes with a filter test certificate, detailing RF and VSWR performance.




Final question: "will it result in more QSO's yes/no?"

Let's evaluate that in a few months.

For now I have to catch my next shift in the ARRL DX CW contest at our clubstation PI4TUE.
Have fun guys!

Feb 10, 2010

Cleaned up the measuring table/solder corner

Cleaned out the soldering table

Installed two wooden shelves

Lined up the equipment at one side




Notice the army CW key?


Feb 2, 2010

Doing it wrong..

CQWW 160m CW
My favourite contest.
These last few years I have hardly had time to participate seriously from anywhere.

Excuses, excuses
There's never been any time to prepare myself correctly (make that: I never took the opportunity..etc). Haven't built any decent station after my move to this new QTH. Not even the smallest 160m TX antenna. Not even a low dipole.
I do argue with others about which rig to buy or how to optimize for best performance on 160m, but have not made a single 160 QSO from this city lot yet. Go figure.
Last year there was this great QST article on the 160m No excuses homebrew vertical from John Miller, K6MM. I tried to build my version of a backyard vertical, but the neighbours strongly opposed to its physical exposure. And so it ended.

Even worse preparation for 2010
Now work goes before hobby and you better plan things ahead. Taking some days off is a good start. Arriving home at 01:15 AM after ploughing 150km through heavy snowfall, an earlier delayed flight, on a thursday morning and then try to catch-up the 'normal work' on the two left days of the week, is not a good start.
On saturday morning I awake early and monitor the progress of our club station PI4TUE in the CQWW 160m CW contest. They have a great TX antenna, using full size slopers from some 70mtrs(220ft) AGL. But they totally lack any RX antenna. Local environmental noise is such high that all past field experiments failed. It is frustrating to hear them miss all dx I can easily hear on my backyard small 160m RX reference vertical
I arrive at PI4TUE in the afternoon and take my shift from 15:00 till 18:00 UTC. After that I'm completely exhausted, cannot even stay to support the others and head home for a 12 hour sleep.
Sunday isn't any better so I go out for a 3 hour walk to catch some energy again.

3830 archives
Dink, N7WA offers a great service via the 3830 list and it's great fun to read the sopabox comments.
I'm flabbergasted by some of the low power/long wire entries; one European OM making 512 QSO's, 8 states and 52 countries using 5W and a 42mtr longwire ....

Lesson learned
Waiting & debating for the new & better station set-up can be an endless frustration.
Next time I will throw out some wire in a nearby tree, connect a tuner and use 100W,
just for the weekend. And operate from my own shack, just having fun.
And have my own decent cappuccino

Ugh!