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Skunked on my day out.

July 16th, 2017 |

Author: Mike VE9KK

The setup in the car

The CHA P loop

On Saturday wife and I had some errands to do in the town we used to live in, it's about an hours drive from were we are now. Julie had an appointment that would last for approximately 2 hours so I felt bringing the Elecraft KX3 would help pass this 2 hour time slot. I brought along my new loop antenna from Chameleon CHA P loop antenna . (A review of this antenna is coming soon) The weather was great and I had my spot preplanned out, it was along a river that flowed through town and there was a nice picnic table there that I have used in the past. Once I dropped of Julie for here appointment it was off to the river, I found there was a wedding shoot going on and the table was not gone! I then had to scope out a new spot which did not take long. The new spot was in a parking lot at the entrance to a park, not the same view as the river side setup but it will do. I was keying out CQ for about 1.5 hours with no answers but I did hear some stations but they were already in QSO's. I did check the Reverse Beacon Network to make sure my CW signal was getting out and it was, the conditions were good as well but I guess it was just time for me to give my CW fist a workout. As always Murphy seems to make his visit at least once on my outings. On this day Murphy decided to make my CW operations a bit more challenging. For a long time I have been using the Palm Radio's Mini Paddle. I find this paddle to be very smooth and very well made. A number of years ago the folks at Palm Radio sent me their newly revised cable that goes from the rig to the paddle. It was lighter and more easy to work with and a great improvement over the more bulky cable that was being used in the past. I have owned this cable for about 5 years without any issues until yesterday on my outing. The end that plugs into the paddle had come apart, the two parts are held together by a screw. I thought at the time I just failed to check the screw and it came loose. I did not have a mini screw driver with me so I had to very carefully plug the connector into the key. Once I got home and upon closer look I realized the connector was broken and the only choice I had was to glue the two pieces together. I did this and it worked fine but in the end this is a one time fix. Overall I made no contacts but it was nice to get out and just have the enjoyment of getting on the radio and it's very relaxing.

Reverse Beacon Network

The broken connector

Skunked on my day out.

July 16th, 2017 |

Author: Mike VE9KK

The setup in the car

The CHA P loop

Reverse Beacon Network

The broken connector

Operating Bicycle Mobile with Mike Nickolaus, NF0N – ETH073

June 16th, 2017 |

Author: Curtis K5CLM

Thinking back to when I was a kid, I used to love riding my bike. My friends and I would get up early every morning and go riding our bikes for about an hour before school started. Then after school we would leave and ride our bike for another two hours or so until it was time to go home for supper.

I wasn’t a ham back then, but I sure loved that bike. Fast forward a few years to my junior year of high school when I got my ham license. I didn’t ride my bike so much anymore, because I didn’t live in town anymore and would’ve been a seven mile ride to and from school and on roads that probably were not the best roads to ride on.

I did start to merge the hobbies somewhat around this time though, however it isn’t anywhere near what Mike and the rest of his club does on theirs. I would clip an HT to my belt and the speaker mic to my shirt and that was the about it.

In today’s episode, Mike talks with me about how he does it, how he operates while being Bicycle mobile. We talk about some of his experiences and some contacts he has made.

Http://www.everythinghamradio.com/podcast/73

Even better low-pass filters for transmitters

November 27th, 2016 |

Author: Sverre LA3ZA

The last issues of QEX have featured two interesting articles by Gary Cobb, G3TMG. He outlines the advantage of using Zolotarev designs for the harmonic suppression filters of transmitters, giving even better suppression of the second harmonic than the more common Chebyshev or quasi-elliptic filters.

Chebyshev low-pass filter from the GQRP data sheet (issue 1)

My interest in this was triggered by the test of the Ultimate 3 QRSS/WSPR kit from QRP Labs in the Nov 2016 QST. The review was positive overall, but it was remarked that the harmonic suppression does not meet FCC requirements (-43 dBc or better). I am not sure whether this is due to PCB layout issues, or if better filters can alleviate it, but I note that the design uses the simplest filter of the ones I have listed here.

The evolution of filters for use for harmonic suppression follows at least these three steps:

Chebyshev type I filters with equiripple in the passband and a monotonically falling, maximally flat stopband. A 7-pole version with three inductors and four capacitors in a pi-network has been around for a while, in e.g. the old recommendation from the GQRP club. It was based on the QST paper “Low-pass filters for amateur radio transmitters,” Ed Wetherhold, W3NQN, Dec. 1979. Two designs for a 20 m filter were given there:
1) Max. ripple in passband: 0.00731 dB, attenuation at 28 MHz: 40.7 dB
1) Max. ripple in passband: 0.00960 dB, attenuation at 28 MHz: 34.5 dB
Second-harmonic optimized low-pass filter from the
GQRP data sheet (issue 2)
An improved stopband was the topic of W3NQN’s article “Second-harmonic optimized low-pass filters” in QST Feb. 1999. Here there is one additional capacitor as the central inductor is made into a parallel resonance which gives a zero in the stopband, based on an idea by Jim Tonne, WB6BLD. The design goal is that this zero should be at the second harmonic frequency. W3NQN proposed to call this a Chebyshev filter with a zero (CWAZ) filter, but it is more correct to call it a quasi- or pseudo-elliptic filter as remarked by G3TMG. It increases the attenuation at the second-harmonic in the 20 m design to better than 60 dB. This design is the basis for the current (Issue 2) G-QRP technical sheet. This would also be interesting to test in the QRP Labs Ultimate 3 transmitter kit.
Zolotarev low-pass filter from the Nov/Dec 2016 QEX article
G3TMG in the new QEX articles has noticed that the passband is over-specified in the above filters as the lower 60% or so of the passband is unused. The Zolotarev design allows for more passband ripple in this part where it does not matter. The advantage is even better stopband attenuation. A measured example for a 60 m filter has a passband ripple of 0.17 dB and a stopband attenuation at the second harmonic of 71 dB. This filter has the same component count as the previous one, but the filter is no longer symmetric like the two previous ones. The increase in second-harmonic suppression is not as great as the going from the first filters to the second, but should still be worth the effort.

The papers, which are well worth reading, are:

Gary Cobb, G3TMG, Zolotarev low-pass filter design, QEX, July/Aug 2016.
Gary Cobb, G3TMG, A more efficient low-pass filter, QEX, Nov/Dec 2016.

The post “Even better low-pass filters for transmitters” first appeared on the LA3ZA Radio & Electronics Blog.

Even better low-pass filters for transmitters

November 27th, 2016 |

Author: Sverre LA3ZA

Chebyshev low-pass filter from the GQRP data sheet (issue 1)

The evolution of filters for use for harmonic suppression follows at least these three steps:

Chebyshev type I filters with equiripple in the passband and a monotonically falling, maximally flat stopband. A 7-pole version with three inductors and four capacitors in a pi-network has been around for a while, in e.g. the old recommendation from the GQRP club. It was based on the QST paper “Low-pass filters for amateur radio transmitters,” Ed Wetherhold, W3NQN, Dec. 1979. Two designs for a 20 m filter were given there:
1) Max. ripple in passband: 0.00731 dB, attenuation at 28 MHz: 40.7 dB
1) Max. ripple in passband: 0.00960 dB, attenuation at 28 MHz: 34.5 dB
Second-harmonic optimized low-pass filter from the
GQRP data sheet (issue 2)
An improved stopband was the topic of W3NQN’s article “Second-harmonic optimized low-pass filters” in QST Feb. 1999. Here there is one additional capacitor as the central inductor is made into a parallel resonance which gives a zero in the stopband, based on an idea by Jum Tonne, WB6BLD. The design goal is that this zero should be at the second harmonic frequency. W3NQN proposed to call this a Chebyshev filter with a zero (CWAZ) filter, but it is more correct to call it a quasi- or pseudo-elliptic filter as remarked by G3TMG. It increases the attenuation at the second-harmonic in the 20 m design to better than 60 dB. This design is the basis for the current (Issue 2) G-QRP technical sheet. This would also be interesting to test in the QRP Labs Ultimate 3 transmitter kit.
Zolotarev low-pass filter from the Nov/Dec 2016 QEX article
G3TMG in the new QEX articles has noticed that the passband is over-specified in the above filters as the lower 60% or so of the passband is unused. The Zolotarev design allows for more passband ripple in this part where it does not matter. The advantage is even better stopband attenuation. A measured example for a 60 m filter has a passband ripple of 0.17 dB and a stopband attenuation at the second harmonic of 71 dB. This filter has the same component count as the previous one, but the filter is no longer symmetric like the two previous ones. The increase in second-harmonic suppression is not as great as the going from the first filters to the second, but should still be worth the effort.

The papers, which are well worth reading, are:

Gary Cobb, G3TMG, Zolotarev low-pass filter design, QEX, July/Aug 2016.
Gary Cobb, G3TMG, A more efficient low-pass filter, QEX, Nov/Dec 2016.

The post “Even better low-pass filters for transmitters” first appeared on the LA3ZA Radio & Electronics Blog.

Taking your QRP signal to the next step.

October 23rd, 2016 |

Author: Mike VE9KK

I was reading NY4G's blog a week or two ago and came across a great post that I wanted to share with my readers. I emailed him about reposted it but never heard back so here goes.......It is full of great DXing tips!

DXing Tips For Little Pistols Like Me

OK I admit it I am more often than not a little pistol. More than likely, I am trying to make a contact at 5W.

Keep in mind two things - the heavy lifting is done not by you but by the DX who is trying to dig you out

of the mud. Some are more willing than others. Of course, the second thing is your persistence. If you

don't go away after he has worked stronger stations - chances are he will try to work you.

http://ny4g.blogspot.com/2016/10/dxing-tips-for-little-pistols-like-me.html

Taking your QRP signal to the next step.

October 23rd, 2016 |

Author: Mike VE9KK

DXing Tips For Little Pistols Like Me

OK I admit it I am more often than not a little pistol. More than likely, I am trying to make a contact at 5W.

Keep in mind two things - the heavy lifting is done not by you but by the DX who is trying to dig you out

of the mud. Some are more willing than others. Of course, the second thing is your persistence. If you

don't go away after he has worked stronger stations - chances are he will try to work you.

Here are some additional tricks to slay that DXing dragon I learned from Brian Smith WO9I. Some are

verbatim and some are paraphrases. Some I omitted but most I kept. Some I added to from my own

experience. Here is the URL: http://www.ybdxc.net/2014/10/14/25-dxing-tips-for-the-little-guy/

(1) "Sharpen your sword. Never embark on a DX quest without first tuning-up your rig. Make sure

your PA is not putting out into a high SWR situation - wasting your meager power into heat as

feedline loss. Sometimes you get only one shot at a rare station before the rest of the world

catches up with you."

(2) See which bands are open before starting the hunt. Bandconditions.com is a good resource.

A reading of 100 for a band indicates that your 1 watt or 5 watt signal stands a good chance

of being heard. Yet another way to do it is to listen for the band beacons. Make sure your foray

into the ether is worth the effort. WWV (at 5, 10, 15 and 20 MHz) gives propagation info at 18 minutes

past every hour. Look at the cluster and listen for on-going QSOs. See how strong the signals are in

the cluster spots - even if it is a country you don't need. If you are looking for an entity in the

Balkans - see how loud the DX are around your hunting ground.

(3) Never send “CQ DX.” Rare and even not so rare DX station seldom answer such calls, especially

when transmitted by weak signals.

(4) Use the contests. If you could operate only a few days a year, I’d pick the weekends of the major

international contests such as the CQ World-Wide, the ARRL DX Contest, CQ WPX, and so forth. I

gnore your score; the idea is to bag DX,you need for whatever - DX Marathon, DXCC, band slots.

These events are like for the little kid in the candystore - except you are truly a little kid

(or a small fry). During contests, the bands are crawling with stations, some rare and some not so

rare. If you are doing DX Maraton - you need most of if not many. The QSOs are short, and best

of all, wide dispersal of the big guns.

(5) After the contest, hang around, to see if rare stations—particulary DXpeditions—want to hang

around to see if anyone else wants to work them. The big guns are usually in their holsters by

then, which is exactly why you’re still blazing away.

(6) Peek into the DX alleys, which are usually located just inside the General band

(14.026 Mhz, etc.). On non-contest days many rare stations hang out here. However, these are also

the most congested places of all. But hey, sometimes the propagation gods smile on you.

(7) Know when to quit. Don’t spend your life trying to break pile-ups; when the band’s open,

there’s plenty of good stuff elsewhere (usually from the same region), and lots of big guys don’t

know how to root it out. How to tell good odds from bad? Good odds: the DX station is booming,

the op is working stations quickly, other station from your call area are getting through, and/or you

don’t hear much competition. Bad odds: weak DX station, slow op, propagation favours other call

areas, pile-up is loud and limitless.

(8) Nail the newcomers. Now for real guerilla tactics: Move to the slow edge of a band and,

tuning slowly accross it, listen for the sound of any station coming on the air, such as a

“tuning up” signal, “QRL?” or of course, CQ. Should one of these surface, stop immediately and

listen for an ID. (Ninty-nine times out of 100 it wont be rare DX, but trust me: that 100th time will

more than make up for it.)
Late means wait. As you’re hunting stations coming on frequency, also check for QSOs that are

about to end (“73,””TNX FER QSO,” etc.)—and wait for an ID.

(10) Develop DX ears. DX signals rarely sound like statesiders. They’re weaker and more

unstable (and those which cross over the North Pole sound “fluttery”). Teach your eardrums

the difference.

(11) Be watchful for 10 or 12 meter openings. Ten meters is the little guy’s equalizer. When the

surf’s up on 10, the DX comes in waves, and a puny signal (even a 5 watter) floats just fine.

Ten meters tend to open to a small geographic area at a time (meaning less competition); also,

signal strength can fluctuate wildly within a few minutes. If you find a new one that’s too weak to

work, lock on to it and relax. Within 15 minutes its signal may peak, giving you a clear shot.

(12) WFWL (work first worry later). If an exotic-sounding station appears, don’t look up its

QTH—pounce! I once heard a 3B8 sending CQ. “What’s a 3B8?” I wondered, but the second he

stopped transmitting, I chased him. Only after the QSO did I discover I had just worked Mauritius.
Rehearse. Rare DX stations are sometimes barely audible, or covered with QRM. A trained ear

can pull them through, but an untrained ear hears only clutter. So hone your hearing. Practice

working common DX stations (such as G’s and JA’s) with faint signals.

(13) Upgrade. Much of the delectable DX swims in the extra portion of the band. Thus reeling it

in is often a question of “How low can you go?” Remember, only 7 percent of all American

amateurs can operate in these murky depths.

(14) Rock around the clock. DX conditions vary with the time of day, so don’t just operate from

7 to 9 o’clock every evening. Vary your routine: Stay up all night on a Friday, rise before dawn

on a Sunday. Remember, sunrise and sunset can produce interesting conditions, so try

them often.
Turn lemons into lemonade. “Bad breaks” aren’t always what they seem. Sometimes they even

work to the little guy’s advantage. Example 1: While trying to work a weak ZK1

(South Cook Islands) during a contest. I was dismayed when a loud Californian began blasting

away on a nearby frequency. Then I realized that because of the W6, most people who were

casually tuning around wouldn’t hear the ZK. During brief lull I caught his “QRZ?”, jumped in,

and nailed him instantly. Example 2: A T3Ø (West Kiribati) operating SSB dodged a stateside

pile-up by QSYing to a U.S. CW-only frequency. Just one American moved with him—yours

truly, who fired up a key and worked him cross-mode.

(15) Talk the talk. Even with Q signals, all CW stations don’t sound the same. DX stations favour

expressions such as “TKS” (instead of American “TNX”) and “DR” (as in “DR OM BRIAN”).

Soviets often close with “DSW” (a Russian good-luck term). And of course, stations whose

transmissions alternate between “599 K” and “QRZ?” are often worth working. Familiarity with

international callsigns helps, too, as I learned one evening in 1988 when I tuned in Y88POL.

Just another East German, right? But wait! East German suffixes usually have only two

letters … hmmm. Moments later I worked a new one—Antartica.

(16) Less is Morse. Not only CW is less popular than SSB (decreasing your competition), but

it’s more effective in marginal conditions—a plus for weak stations.
Read the news. Serious operators learn about DXpeditions and such by subscribing to publications

such as QRZ DX? and The DX Bulletin. And for those with packet capability, lots of DX packet

clusters spot rare stations.

(17) Never assume. Once, during a Boy Scout jamboree weekend, I heard a Liberian station with

a special callsign, using scouts as ops. No one was answering its CQ, probably because

everyone believed the station was working only fellow Scouts. But when I asked, “Are you

working only Scout stations?” I was rewarded with a “No, you’re 5 by 6”—and a new one.

(18) Beat the bushes. Many people think all the primo DX hangs out on the low ends, but

that’s a fallacy. Ever work Moroco? I did—on a 10 meter Novice CW frequency! And I once

heard Zimbabwe on 21.080. Moral: Don’t just look in the clearings; rummage through the high

weeds, too.
Listen for swan songs. Normally, when sunspots are high, upper HF bands such as 10 and

15 meters close in the evening. During their final moments, however, strange conditions

sometimes occur. Try to catch each band just before it gives out (see whether any signals are

audible; if so, tune around). As the band dies, most of your competition will give up and

head south. I bagged my first CEØ (Easter Island) under such conditions.

(19) Check and double check the DX call. Don’t just scribble down a DX callsign; make

absolutely certain you heard it correctly. On CW I’ve worked lots of ops who can’t tell a “4” from

a “V” or an “H” from an “S.” Missing even one dot in a call sign can turn a prize catch

into a busted QSO.