Posts Tagged ‘Ten-Tec Eagle’

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. 


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

Rich, AA4OO

Bugging Out

Vibroplex Bug QSO

Sometimes I'm in a mood to use my bug.  I'm still a relatively new CW operator and using my Vibroplex Original Bug is both novel to me and a challenge compared to my Kent Straight Key or using paddles.

The key lineup with the Bug in the center
I purchased my bug used on a well known auction site for about $65.  It dates to sometime in the mid 1970s but it doesn't differ much from bugs made in the past 75 years.  I have added some weight to slow it down to around 19 wpm DITs by taping a heavy spacer onto the factory pendulum weight as well as adding a heavy metal spacer to the end of the pendulum.  The weight on the end of the pendulum is held on by a simple plastic drywall screw anchor.  I can pull the weight off the back quickly if I want to let it go up to about 25wpm DITs.  Without the extra weights this bug sends at around 27wpm at it's slowest speed and up to... well I don't know how fast because I can't control it at the fastest speed yet and I certainly can't copy others at that speed so I usually keep it below 20wpm for now.

If you haven't used a bug I encourage you to give it a try.  It's a challenging key to get the hang of but the effort to learn it is fun and rewarding. I especially enjoy the tactile feedback from that swinging pendulum and the the click-clacking of the pendulum against the hanging damper.

I was using my Ten-Tec Eagle (model 599) purchased used from a local ham.  The Eagle is a super little QRO radio although in this QSO my output is 5w.  If you have sharp eyes you may see that the power level is set to 7w but that is actually 5w output according to my external meter.  The 100 number under the CW symbol is the bandwidth that I was using.  I generally keep the bandwidth at 500 Hz but there was a station operating above us that I wanted to mask.

Ten-Tec Eagle 599
The Eagle is a great CW rig.  This model has 3 front end crystal filters 2400Hz, 600Hz and 300Hz giving it nice selectivity for any mode. 

I was working Ed, KG4W in VA who is an SKCC member.   If you want to work other manual key stations 3550 kHz is a calling frequency for the SKCC.  Ed told me during the QSO he was using a VIZ vertical bug which is a unique and interesting bug design.  

He reported my signal as 599 and he was 599 as well.  I was running 5w output power to my 80m OCF Dipole. He was using an Yaesu at 100w to a fan dipole.  5w was sufficient for this QSO but if he had reported me as 559 or weaker I would have raised my power to 20w to make copy for him easier.  I enjoy using QRP but when I rag chew I don't want to make it difficult for QRO stations to copy me if I can help it so having the Eagle allows me to raise my power if necessary for the communication.


So here's the qso between two bug operators.  I hope you enjoy it...

That's all for now

So lower your power and raise your expectations


Richard, AA4OO

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