"Help" for an Old Neubie, LOL!

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ka5lqj

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Morning Friends,

Pease forgive me, I'm not the brightest crayola in the box. I know nothing about SDR other than what the letters stand for. :(

I do know it may involve a computer, but how powerful or the type O/S it may use is a mystery to me. So, I have a few ideas & questions to ask, if that's ok.

#1. What of equipment does it take besides the software program?

#2. Does it run thru a sound card?

#3. Is there a cut-off as far as low frequencies go? Say 300kHz?

#4. Is there a cut-off as far as high frequencies go? Say 3gHz?

#5. Are ALL modes (Cw, AM, LSB, USB, FM, Digital) used?

Ok, here are the "ideas":

It certainly be nice to have a receiver/scanner that could make use of all the different modes (except encripted) from say 300 kHz (kcs.) in the Longwave band up tp say 3 gHz (gcs) in one unit. Now, I'm not sure if a Netbook would meet the criteria of a computer powerfull enough to handle the software but, if so, it could be used mobile. :lol:

I don't imagine it being used to transmit on all those frequencies, but if you do have such a that, only blocked from transmitting on anything but the Ham bands, someone will come along, snip a wire, remove a diode and have the transmit capability all up and down the receive portion of the band.

I'm medically disabled and would enjoy having such a radio that I could control without a lot of effort. IF and when I have my liver transplant, I'll be confined to complete bed rest for almost 4 months the Dr's said. :( Then, two more months of just taking it easy. I'll have to move to Dallas, TX to stay near Baylor University Hospital, which is a great medical facility.

Ok, time for me to sit back and "listen" to what y' all have to say.

Thank you for your time.
Respectfully,

"Buck"/KA5LQJ
 

rwier

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................................................... I know nothing about SDR other than what the letters stand for..............................................................."Buck"/KA5LQJ
Describes my level of expertise (lol) exactly!!
 

Token

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Morning Friends,

Pease forgive me, I'm not the brightest crayola in the box. I know nothing about SDR other than what the letters stand for. :(

I do know it may involve a computer, but how powerful or the type O/S it may use is a mystery to me. So, I have a few ideas & questions to ask, if that's ok.

#1. What of equipment does it take besides the software program?
It depends on the exact model of SDR used, there are many different models just as there are many different models of traditional ham radio gear.

In general, at a minimum there is one external box that attaches to the computer, often via the USB port. This is the receiving hardware and the antenna connects to this device.

#2. Does it run thru a sound card?
Again, it depends on the exact model. There are two basic types of SDRs, one is a sound card based SDR and does use the sound card to get the data into the PC. The other is a DDC (direct digital conversion) type and does not use the soundcard to get the data into the PC, however to get the sound, audio, out to your speakers you must use the sound card. Just getting any sound out of the PC.

There are DDC designs (such as the QS1R) that have sound output on the SDR hardware as well. In these cases you can attach a set of powered speakers to the sound output of the hardware and bypass the need to get sound out of the PC.

#3. Is there a cut-off as far as low frequencies go? Say 300kHz?
Totally dependant on model. Many DDC SDRs can go very low in freq, say down to just a few kHz, often below 10 kHz.

#4. Is there a cut-off as far as high frequencies go? Say 3gHz?
Again, totally dependant on the exact model. Most SDRs are not oriented toward the world above 30 MHz. But there are several hybrid models that go to above 3 GHz.

#5. Are ALL modes (Cw, AM, LSB, USB, FM, Digital) used?
Yes, that is one of the nice things about an SDR, all modes of modulation are easily supported. For specific digital modes you might need the specific software that works for that mode. Keep in mind that “digital” is a information/data description, not a modulation mode. Digital can be sent in any modulation mode, such as AM, SSB, FM, etc.


Ok, here are the "ideas":

It certainly be nice to have a receiver/scanner that could make use of all the different modes (except encripted) from say 300 kHz (kcs.) in the Longwave band up tp say 3 gHz (gcs) in one unit. Now, I'm not sure if a Netbook would meet the criteria of a computer powerfull enough to handle the software but, if so, it could be used mobile. :lol:
In general todays SDRs are more suited for communications receiver type applications, not “scanner” types of applications.

There are a few hybrid SDRs that are fairly good as scanners also. However these tend to be pretty pricey if they really are SDRs. The WinRadio G3XX series (G315, G305, etc, not the G31DDC, G33DDC, or G39DDC) are arguably not SDRs, although the vendor does advertise them as such.

The AOR AR2300B does cover 40 kHz to 3150 MHz, and does function as a good scanner, but for $3600 it is on the pricey side.


I don't imagine it being used to transmit on all those frequencies, but if you do have such a that, only blocked from transmitting on anything but the Ham bands, someone will come along, snip a wire, remove a diode and have the transmit capability all up and down the receive portion of the band.
Very few SDRs are transceivers, most are receive only. The most notable transceive SDRs are the Flex Radio series. The Flex series do not have the kind of bandwidth you are talking about, they are meant to be ham band only and HF/6M, although in the last couple years they have added 2M and 70cm to them.


T!
 

ka5lqj

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Joined
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Messages
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Location
Near Lakeview, LA (Caddo Parish)
"Thanks"

Thanks, Token,

Your information is just what I needed to know. I have an Icom 706 MarkII-G
transceiver that has a built-in short and long-wave receiver in it. It starts down about 300 kcs, but has very poor ability to hear stations. It will go as high as 470 mcs on receive or transmit. I was hoping to use the SDR as more of a radio, than a scanner. I'm not sure HOW you would set that up to change frequencies when a signal came up.

Now, if someone came up with such a "radio" with a monitor scope to see where the frequencies are active (Pan adapter?) I'd just have to save uQp to buy one, LOL!

Right now, I'm trying to get this old, DELL 2400 in shape to use Kbuntu Linux and get away from Windoze. I've got some Part 90 spreadsheets to change over and some antenna modeling to do and I don't need to be bothered fighting spam bots, maleware, unwanted e-mail and my address book compromised. I'm going to lock it down tight.

Take care,
Thanks again,
73,

Buck/KA5LQJ
2AU368 <== Australia United DX CB club.....Mud Ducks! Qwack! Qwack!
 

Token

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Jun 18, 2010
Messages
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Mojave Desert, California, USA
Your information is just what I needed to know. I have an Icom 706 MarkII-G
transceiver that has a built-in short and long-wave receiver in it. It starts down about 300 kcs, but has very poor ability to hear stations. It will go as high as 470 mcs on receive or transmit. I was hoping to use the SDR as more of a radio, than a scanner. I'm not sure HOW you would set that up to change frequencies when a signal came up.

Now, if someone came up with such a "radio" with a monitor scope to see where the frequencies are active (Pan adapter?) I'd just have to save uQp to buy one, LOL!
Most SDRs have a significantly better receiver than the 706 Mk-II G, particularly DDC SDRs. Also remember the advantages of an SDR over a traditional receiver, typically much better filter performance, continuously variable filter widths often from 10 Hz to 25 kHz widths, the visual representation of the spectrum, etc.

And to change frequencies there are several ways, you do it just by typing in a new freq, clicking the up/down arrows on the keyboard, clicking on a signal on the waterfall/spectrum display, rolling the mouse scroll wheel, or turning the jog/shuttle knob (if you have one). Turning the Jog/Shuttle makes tuning an SDR pretty much like any old radio, turn the knob and tune.

Such radios as you have described, a traditional looking radio with a monitor or pan adapter, are made. More importantly it is often possible with many different traditional radios to add an SDR to the mix, monitor the IF output of the traditional radio, and make the SDR a pan adapter for the radio. The only requirements are that an unfiltered IF needs to be in the frequency range covered by the specific SDR (such as the common 10.7 MHz IF) and there is some way to get the IF out of the radio. Some radios, from the factory, bring the IF out to a port on the back, for these it is often just a matter of plugging the SDR in to that IF and you are ready to go. Other radios require the user to make minor modifications to the radio to bring the IF out of the chassis to the SDR.

SDRs like the RFSpace SDR-IQ are tailor made for applications like a pan adapter. In fact, although the SDR-IQ works pretty well as a stand alone HF receiver (1 kHz to 30 MHz) I think it was originally intended and advertised as a pan adapter.

T!
 
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