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LukeH

Cw

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ok. This is more of a ham radio operations question than a ham + geocaching question, but I find that this forum has a great many hams on it and hopefully somebody can give me some advice.

 

I just got a 20 meter CW rig, the transmitter operates at 14.06. Fully amplified I get about 5-10 watts of power, pretty much QRP. I have a 10 meter long dipole and with this rig I can receive signals all day. But I have tried contacting people, to no avail.

 

I'm not sure exactly how to operate. I would think that if you tune your receiver to exactly your xmit frequency, you will only hear clicks and not the cw tone. If you tune a bit above or below, you can hear the tone (makes sense.) Is there a convention for how far to tune and in what direction?

 

Thanks to anyone who can help out

 

Edit: I goofed one of the numbers.

Edited by USAFA05

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Depending on the radio, you should be able to zero beat the signal using your side tone. Your tone should match his tone in frequency. You shouldn't hear clicks...at least not that I'm aware of. I'd throw out the CQ and see what you get back!

 

Dino - K6RIX

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good luck on making a 20 meter contact on weekends via QRP. they are a bit arogant there. I agree with above reply. start whipping out CQ/QRP and see what happens. You should hear a tone though.

Good luck

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It might help if you described your rig. The way you described it, it sounds to me like you have a transmitter/receiver and not a transceiver. If that's the case, there's a bit more to tuning when your transmitter and receiver are separate.

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On top of it all, 20m is not a great QRP band. In fact, 20m could be considered a QRO band.

 

Still, you might get lucky. When you are QRP, the antenna is VERY important! Get it right.

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Right, sorry I hadn't mentioned that. My receiver and transmitter are separate.

 

I figured 20m might not be the best band, but while there were a couple options available, all QRP, this was the only one I could afford for now. When I get back to school, I'll use the club equipment which is all set up and has all the power I need.

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Sounds like you have a half wave dipole. This is good. If you can borrow an SWR meter you can test it. Since you have a separate transmitter and receiver, send a tone and tune the receiver (use no antenna, or a small wire or dummy load on the transmitter) to hear it at the side tone set in the transmitter, probably about 650 -700 hz. Then hook up the rigs to the antenna using an antenna switch or however the 2 rigs work together.

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Right, sorry I hadn't mentioned that. My receiver and transmitter are separate.

I don't think 20 is that much less QRP-friendly than the other bands.

 

If your transmitter and receiver are designed to work together, and on CW, the receiver will have what is called a Beat Frequency Ocsillator (BFO). If you pick up a CW signal you should not hear clicks, you should hear a tone. By tuning 200 to 300 cycles (NOTE: that is cycles, not Kilo-cycles). you get a reasonable tone.

 

If you can't hear a tone when you transmit, but can hear other signals, you are not transmitting.

 

Try sending "KC0RIQ testing" as you tune your reciever up and down from, for example, 14.02 to 14.08 MHz. If you don't hear anything, it is your transmitter--again, assuming you can hear other stations.

 

What kind of T/R switching are you using? If you have one antenna, you need to switch it between the transmitter (T) and receiver ®. I once had a set where thwi was a manual switch, most sets since the invention of the pin diode have automatic T/R switching.

 

What brand and model radios are you using? Some of the sets on the market, like the kits available from Ramsey, can be used effectively but have some quirks in tuning. Specific would make it easier to help you.

 

Good luck, and welcome to QRP CW!

 

Dave_W6DPS

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Thanks for all the help so far. The rigs are the Ramsey kit ones that Dave mentioned. I also have the RF amplifier because the transmitter by itself puts out less than a watt. If I hook it inline with my transmitter I get between 5-15 watts depending on how fresh my batteries are. I don't have a 12-15 volt wall adapter that can put out the 3 amps the amplifier needs, so I use alkaline cells which seem to be able to source enough current to run everything.

 

Those power numbers are just estimates which I got the old-school way, by running light bulb dummy loads. Admittedly not the most effective way, but they are about where the manual said they should be. At least I know I am getting power out of the rig.

 

The manual for either set mentions that many people choose to use it together with the other one, and they give some info about that, so it seems safe to conclude that they can work together. But the help is not as comprehensive as I would have liked.

 

The antenna line passes through the transmitter and on to the receiver. This works fine for receiving operation, but I overload the receiver if I transmit like this, so I built a manual switch to disconnect the receiver from the antenna when I want to transmit. It seems to work ok, but please let me know if there's a better way to do it.

 

The receiver uses varactor tuning, and by design covers about 300 kHz. I changed a capacitor in the tuning circuit so that it would cover a smaller region of the band, then retuned a coil so that the receiver covered the part of the band where I heard all the cwto include the region of the band that my transmitter can hit: 14.06 MHz +/- about 5-10 kHz.

 

The antenna is a half wave dipole, each element 16.7 feet long. I have an RG59 coax feed line. I am not sure how good an idea it is to use coax, but it's all I have at hand right now. I can switch it out in about a day if it turns out coax was a really bad choice. I also have 5 feet of copper pipe hammered into the earth, that I can use as a ground.

 

One more thing. Here's what I meant when I mentioned I heard clicks. I keyed my transmitter, then tuned my receiver from one end to the other. It would pick up the tone which would decrease in pitch as I tuned, then would go away. As I continued to tune I would start hearing it again, and it would increase in pitch. Right in the middle is where I heard no tone, and where I would hear clicks if I keyed the transmitter.

 

Again thanks for the help so far. That's one thing I like - hams are always willing to give advice & help out.

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Ok USAAFA05, They pretty much told you what you need I would also say If you do not have the right Antenna for the Band , then you do not need to try to transmit otherwise you can Damage or burn up somethings inside you Radio.

 

20mtrs is tuff running 100 watts,,,, If you have 4oo-500 Watss then it's ok or More up to the Legal limit 1500.

 

So you may need to find a Antenna either make one out of copper stranded wire or build one out of alum. but it has to be correct or your SWR's will be high up & down the band.

 

Happy Hunting

WV5V

Continouswave :(

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