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This is not the wattage you’re looking for… move along

Getting hot under the collector/base junction

Where did my power go?

My Elecraft W1 power meter has been absent from the antenna chain for a while due to a jumper cable shortage when I last reconfigured my shack.  But now the W1 meter is back in the chain and it revealed something a bit worrisome about the 1Watter transceiver...

I've had a bunch of QSOs using the 1Watter both in the shack and in the great outdoors.  The 1Watter is my first home built transceiver (albeit from a kit) and has been a great learning experience. It is called a 1Watter (or 1H2O as Diz calls it) because it nominally produces an output of 1 watt.

The Elecraft W1 power meter is a nice, inexpensive QRPp to QRO meter because it measures from 150 watts all the way down to 150mw.

The little 1Watter transceiver does indeed produce just a hair over 1 watt when it's first powered up. Tonight I tossed my call out on 7030 kHz and was promptly answered by N4DR up in Maryland.  He was running a YOUKITS TJ5A at 5w. When we started the QSO my W1 meter showed that my 1Watter was outputting between 900mw and 1w to my mighty attic antenna.  

Then by the second exchange in the QSO I noticed my output power dropping down to 700mw.  By the end of our ragchew my 1Watter output had dropped to 500mw.  

Power meter in background showing 500mw by the end of the first QSO

As I ended that first QSO I was called by another station (AF4YF) who was running a 2 watt homebrew xcvr.  And by the end of that QSO the 1Watter was producing less than 300mw.  I felt that some investigation was in order.

Heat is the enemy

The 1Watter uses a 2N5109 NPN RF transistor for a final. Transistors really are not fans of heat.  


The maximum power output available from a power transistor is closely linked to temperature, and above 25°C falls in a linear manner to zero power output as the maximum permissible temperature is reached.

My 1Watter kit included a friction fit heat sink, seen at the top of the photo below. But apparently this heat sink either saturates quickly or doesn't have sufficient surface to conduct away the heat.  My enclosure is not vented but it is alumunium and I don't feel any appreciable temperature rise above ambient so I don't think venting is in order yet.


I allowed the 1Watter to rest for 30 minutes following the QSOs, still powered but not transmitting.  That only resulted in the output power getting back into the 700mw range.  I'm considering increasing the bias to start with a higher transmit power so that it will maintain 100mw but I'm afraid of destroying the transistor.  I might also try some conductive paste but it's messy and I'm not sure it will help if it can't be pressed between two surfaces.

I'd appreciate any constructive suggestions.  I'm still a noob at this electronics stuff.

But the real moral of the story is...


Band conditions on the evening of this QSO

So as I sat here wondering why my 1 watt radio was only producing a 1/2 watt now,  I reminded myself that I was having extended QSOs using a (now) 500mw radio with other QRP operators (5w and 2w).  I was also using my attic antenna, not some multi-element beam on a tower. Band conditions on 40m were also a limiting factor tonight (see snapshot at right).
These were not simply swap 599 TU QSOs, we were exchanging information on multiple go-rounds with solid copy.

So if you're reading this blog you likely have some interest in QRP.  Hopefully this is just yet another reminder that we often don't need as much power as we think we do for communications.  I was getting discouraged this summer due to the decreasing sunspot cycle and thinking "I'm gonna need to operate QRO more and likely get a real antenna put up in my yard".  

But it's times like this with my 1Watter that keeps reminding me to lower my power and raise my expectations.


So lower your power and raise your expectations...

72 / 73
Richard, AA4OO

Head Copying CW

There's more to using Morse Code than Learning Morse Code

It's been about 18 months since I started learning Morse Code in order to use it for making CW contacts in amateur radio.  Learning the code allows you to recognize the letters, numbers and punctuation but it's akin to when you learned your "letters" when you were a child.  Knowing the alphabet is just the first step to "reading".  So it is with learning Morse Code.  



When I started making contacts using CW it was fairly formulaic. I even had my QSOs written out with regard to what I was planning to send and what I expected to hear during each exchange. 

But then my copy and sending speed increased beyond 17-19 words per minute and I could no longer type or write down what I copied fast enough to comprehend and I began to head copy.

Head Copying

Head copying is when you stop transcribing what you hear and listen to it as you would a conversation and only take notes on salient points.  This was a big step for me and it has been a difficult transition.  

Using Morse Code to communicate at speeds faster than it can be written straddles the weird place between hearing and reading.  We learn morse code by its sound but at slower speeds, say below 30wpm what we are "hearing" is letters, not words so we are having to buffer those letters in our head to spell words.  When we "listen" to someone speak we are not hearing them speak letters but complete words, when we "read" our brains are not looking at individual letters but at complete words.  When we hear Morse code at 20-25 wpm we are hearing very slowly pronounced words and it is a new skill that has to be learned.

This skill is necessary for ragchewing.  A ragchew is a long QSO between two amateur radio operators. This is generally what amateur radio operators are doing on the radio when they're not contesting, ...


How to practice for a ragchew

So after you learn the code, how do you learn to use it in a conversation?  

I struggled with copying ragchew QSOs at 20+ words per minute for most the spring and early summer of 2016.  Just listening to QSOs alone wasn't cutting it for me.  During my lunch time at work I began regularly using my CW training application on my phone to send the top 500 words at 25wpm and it has been a big help to me.  

I had to learn the skill of not just recognizing letters but holding what I was hearing in my brain long enough to turn it into a word and just as importantly not to get hung up on a word that I couldn't immediately recognize but let it go and pay attention to the next.  To me, this has been a bigger learning curve than recognizing the alphabet and numbers at speed.

In addition to learning to buffer the letters until they form a word I must also keep the slowly accumulating set of words in my head until it forms a sentence or makes sense as to what is being communicated.  
THIS IS COMMUNICATION with Morse Code and it is different than anything else we are familiar with so treat it as learning a new skill.

Now if all you are trying to do with CW is contests, you don't need this skill.  You just need to be able to copy a call and whatever designators are sent after it for the contest rules (state abbreviation or a contest number or grid square) and get it copied into your logging program.  But if you want to communicate at speeds above 20wpm you will need this new skill.

Next steps

After you've practiced with machine sent top 100 or top 500 words you'll still need time copying actual QSOs because more often than not, most operators you will communicate with have lousy spacing and run their words together or use so many abbreviations that you'll have to learn to hear the abbreviations as new words.  When I work an operator who runs things together I'll first try to really exaggerate my word spacing during my exchange to give them a hint and if that doesn't work I ask them put more space between their words.  Some will comply, but some folks just don't seem to know how to leave space so I'll catch what I can, politely respond to what I could understand and then move on.

So if you're getting discouraged when you reach a wall of comprehension, try the steps above and with time I think you'll find your comprehension during a ragchew improving and it will take you to a new place in the hobby.

That's all for now

So lower your power and raise your expectations... and put extra space between your words!

73
Richard AA4OO

Update 11/7/2016:

KA8BMA pointed me to a nice reference created by W0XI for the top 100 "Ham Words" used in QSOs... check it out most common ham words

Listen to the music

Comparing CW audio 

The Elecraft KX3 and the Ten-Tec Eagle

The bands were very poor today from my home and finding stations to operate were few and far between, especially at QRP power.  So I thought I'd take a break from operating and create a brief video demonstrating the CW audio differences between the Ten-Tec Eagle and the Elecraft KX3.



The radios

The Elecraft KX3 and Ten-Tec Eagle don't have much in common apart from having DSP architectures and both being from American radio manufacturers.  The Eagle is devoid of bells, whistles and has no-menus.  On the Eagle, what you see is all you get, as opposed to the KX3 which has multiple kitchen sinks stuffed into it's tiny enclosure. 


Setup

Both radios have their pre-amps off and DSP bandwidth set to 500 Hz.  I have the RF gain reduced by about 15dB on each radio since turning up the RF gain on a noisy day like today just makes for white noise.  

During the video I operated the NR (noise reduction) button on the Eagle to demonstrate how it makes a signal pop and in the same manner operate the APF (audio peaking filter) on the KX3.  I end the demonstration by reducing the DSP bandwidth down to about 100 Hz on each radio.  The Eagle has both 600 Hz and a 300 Hz IF filters so it gets a bit of insertion loss when I pass through the 300 Hz setting.  There were no adjacent signals so the IF filtering wasn't doing anything for either radio in this case.

The audio from the Eagle is coming from its built-in speaker, while on the KX3 I'm using an iHome external, self-powered, speaker.  The KX3 has an abysmal internal speaker and there's little point in trying to listen to it compared to a radio with a real speaker.  In my opinion that speaker is one of the few serious flaws in the KX3.  

After I shot the video I realized that there was a bit of a bias against the Eagle's audio because the microphone in the camera was below the top of the Eagle's case and thus wasn't directly hearing the cabinet speaker, whereas it was in direct view of the external speaker connected to the KX3.  The Eagle's audio sounds crisper than this in person when your ears have a straight shot to the speaker.

Subjective listening

Audio is a very subjective thing because people can hear the same thing very differently so I won't comment on my opinion on which I prefer.

I would however be curious to hear other's opinions.


That's all for now

So lower your power and raise your expectations

73/72
Rich, AA4OO

You have two ears but only one mouth

Listen more than you send

In honor of Mothers Day this weekend here in the U.S. we recall what our wise Mothers told us... 
Listen more than you talk because God gave you two ears but only one mouth
Learning CW is more about learning to copy what you hear than sending.  So listen, listen, listen.

Listening to on air CW QSOs using your own HF radio... 

Of course the best CW copy practice comes while listening to stations using your own HF radio and having on-air QSOs. So make the most of your opportunities to listen to live QSOs from your home station.

Find conversations that are at different speeds for your practice copy.  In my experience, when I only practice copying higher speed CW for a time, my ability to recognize slower CW gets rusty so practice copying all speeds.  I was worked by a station some months back when I was sending at only 13wpm who came back on the second exchange and replied that I was too slow to copy and he quit the QSO.  I don't want to be like that.  

Along with copying QRS stations, practice copying stations that are well above your comfortable copy speed in order to stretch yourself. You will likely miss much of the conversation but your ability to start recognizing common words and abbreviations will increase. Another side effect I find is that when I listen to a 25wpm (well above my present copy speed) exchange between two operators who have equally strong signals, I'll usually copy one station better than the other.  I try to figure out why that's the case.  Something about that operator's style is easier to copy and when I discern why that is, I try to emulate it.

I want to be able to copy all speeds of CW; both to encourage new QRS operators and ragchew with the QRQ old-timers.


On Air Practice

Listen to on air CW QSOs using remote radios

When you don't have hands-on access to an HF radio or when propagation is poor at your QTH web SDR stations are great resources for CW copy practice. 

Web SDR stations are accessible from http://websdr.org and allow you to listen to CW anytime you have access to the internet.   Web SDR stations are available from around the world, potentially from countries you haven't been able to regularly hear from your QTH.  So it allows you to hear different sending styles from around the world.


Web SDR station

Listen to machine generated CW

When live CW is unavailable you still have machine generated CW as an option.  Practice copy of machine generated CW is a pale comparison to actual CW QSOs but it has it's uses and it's always available.  The Morse Trainer App for Android devices offers most features standard in other learning applications plus a built-in list of randomized top English words and an e-book reader.

Morse Trainer app for Android


Sights and sounds

This following video demonstrates the copy methods above.



So listen more than you send and your CW copy, as well as your interpersonal skills, will improve with practice at listening.


That's all for now

So lower your power and raise your expectations

73/72

Just the medicine for lowering impedance

Pill bottle balun

Jack-WD4E is a fellow NAQCC member and he sent me one of his QRP creations that I just had to share.

If you are staying on your meds you probably have the perfect enclosure for a QRP Balun.

If I could save RF in a bottle...
Jack encloses his home-brew wound toroids in pill bottles.  
The child and arthritis proof cap keeps the goods away from young and old alike...


Just what the doctor prescribed...



So re-purpose your medicare paid goodness and put it to work for you

Sorry all you entrepreneurs, Jack told me that he's already applied for the patent so you won't be competing with Facebook with this product idea.  He owns it.


That's all for now

So lower your power and raise your expectations

72/73

Where is that blasted noise coming from?

Evil RF noise in Ethernet over power adapters

My internet comes in at a corner of the house.  In that room I have my cable modem and a WIFI router.  Unfortunately the WIFI is seemingly non-existent at the other end of my house and especially in the upper floor opposite the WIFI router.  I tried re-orienting it and different antennas to no avail.

As a solution, I purchased an Ethernet over powerline adapter.  This routed the Ethernet through the house wiring to receivers plugged into outlets at points where the WIFI was weak, thus providing Internet access to those rooms.  The model I purchased also had ethernet ports which I needed for some of my older devices.

Ethernet over powerline seemed like an ideal solution.

Typical Ethernet over powerline adapter
All was well until a few months ago... I noticed a broadband noise on 40m and 80m in my shack.  I turned off the power to the house and switched to battery on my KX3 and the noise was gone.  So the interference was coming from my house.


The Search

I restored the power and fired up my Yaesu HT which has general coverage receive and tuned it to 7030kHz.  I walked around the house and conducted a bit of a fox-hunt for the offending noise.  The noise occurred at every outlet in the house !!!

I tracked it down to one of the Ethernet powerline receivers.  I unplugged it from the wall and discovered blissful silence.  I figured it had just gone bad.  It was out of warranty so back to the store I went and purchased another set.  This time it was a different brand, as the first one was no longer carried.

I installed the new adapters and everything was fine... for a time.


Fool me once shame on you, fool me twice shame on me

This week the noise returned with a vengeance.  Being wiser I went straight to the new adapter and unplugged it.  Yep it had gone bad again.  It was in warranty but I'd learned my lesson.  Whatever sort of RF filtering these devices have doesn't last.  Something zaps them.  I can't plug the receiver into a AC line filter because it stops it from receiving the Ethernet over powerline.

So out they came and back to the electronics store I went.  This time I purchased a WIFI extender with Ethernet ports built-in.  I'm back to blissful RF quiet (to a degree) at my QTH.

The moral of the story

If you have RF noise at your shack and you use these devices, check them out.  They could be the S9 noise culprit.  If you haven't bought them, take my advice and don't chance it.

I didn't think a WIFI extender would work for me because my laptop can't even detect the WIFI in some of my rooms but the WIFI extender (at least the Netgear model) seems to work well.  I now have blessed Internet in every room and no more broadband RF noise.

That's all for now

So lower you power and raise your expectations (and rid yourself of pesky RF noise)

72/73
Richard, AA4OO
http://hamradioqrp.com

The Best CW training app for Android

Morse Trainer for Ham Radio

I'm always on the lookout for useful tools to help increase my copy speed and enjoyment of CW/Morse Code.  Training applications for beginners that teach letters and letter groups are great to get started but after you're making QSOs and copying at useful speeds those apps get a little stale. 

I recently wrote about using the "Morse News" RSS reader application for PCs. What I liked about Morse News was that it would send the text of news articles as CW.  I found it useful as a natural language trainer but I didn't like being tied to my PC during training.  

I wanted a similar application for my smart phone.


Just the mobile ticket to CW training


I'm not sure how I missed the "Morse Trainer for Ham Radio" app up to now but I've been using it for a couple of weeks now and really find it useful.


Morse Trainer in QSO Text Mode


Training Modes

This app has all the standard Morse Code training tools such as letter training, letter groups, callsign training etc. It also can send the most common 500 words as well as a random sample QSO training mode.  That's all great but what I really find useful is the ability to send your own text that you type or paste into the app and even... wait for it... an ebook reader!  

I must really be a geek but I find the ebook reader makes this a must have CW training app for me.  I converted some of my ebooks into plain text (using Calibre) and placed them in the CWTrainer's application folder on my smart phone.  I then choose the ebook mode, choose a book and it will send it as CW to me and keep track of where I left off.  I use this ebook reader mode to break the monotony of my long drive time.  

ebook mode

It's great fun to witness the expression of the person beside you at a stoplight hearing Morse Code pouring out of your car.  Priceless.

I keep the speed higher than I can comfortably copy so I'm missing some of what is sent. There's nothing like reading an action novel where you're missing half of what's going on. Did Tex get shot or not? I missed that word, hehe.

While this app doesn't read RSS feeds like Morse News application for PC's the text and ebook reader modes more than make up for it. The only bug to-date that I've noticed on my phone is that if I rotate the phone while it's playing it will reset where it was reading from back to the beginning. 

Here's a video from the application's author describing it's functions...


And here's a link to the application in the Google Play store.

https://play.google.com/store/apps/details?id=com.wolphi.morsetrainer

I have no affiliation with the maker of this application.  I just wanted to share.



That's all for now

So lower your power and raise your expectations

73/72
Richard, AA4OO

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  • Matt W1MST, Managing Editor