The world of radio (RF)

Since I am new to the world of radio I have been pummeled by acronyms. I have even started making my own sqlite dictionary just to keep up. One definitition has been hard to nail down.

I see DC mentioned a lot. And I have it defined as Direct Conversion. But then I see things like good from DC to 6GHz and then think I’ve got some gaps in my understanding.

Maybe someone knows of a one-stop page of radio acronyms? I have found some but usually they are outdated or incomplete (or both).

It can mean Direct Conversion, but in that context I would interpret it as Direct Current or 0 Hz as in there is no Alternating Current component to the signal. But the reality of most SDR hardware is that they will not measure the DC component, most have a capacitor on their input to block any DC voltage. If you were really interested in the DC bias of a signal an oscilloscope of a multi-meter would be a better instrument to measure it.

As for a list of every radio acronym, I’ve never seen one, but if I ever see a TLA or ETLA and I’m stumped I usually just ask. There are lots of people happy to correct you, or point you in the right direction -

DC or 0Hz is the same.
So yes, 0-6GHz is what is meant.
Most products that I’ve seen that state 0-6GHz are usually Analog Devices based analog to digital converters.

In reality, achieving that outside the ADC requires lots of filtering, multiple filter circuits that are switched.
A good example would be the Tek 306b spectrum analyzer, which someone did a tear down a while back on youtube:

Follow to signal flow in that video, especially the more detailed section.

As far as RF related acronyms goes, and how to pick it up quickly, I recommend coffee and reading. is pretty decent resource of info, while being easy to digest.

Don’t be afraid to ask seemly silly questions, its most often opportunity for everyone to learn something, as more experienced people reply.

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@hTo137 I’m also fairly new to radio although quite well experienced in other areas of ‘engineering’ itself. I tried to put together a list of abbreviations:

and, yes, there are quite a few gaps.

I’m also trying to decipher the Lime GUI (Lime graphical user interface) which has hundreds of as yet unidentified sliders and buttons which don’t appear on Wikipedia searches or any instruction manual.

I really just enjoy the learning experience and don’t feel like I need to understand it all at once. Best tactic is to read all the web pages and watch all the utube videos intensively for a few hours at a time then switch to a totally different activity to allow the brain to process the info in it’s own time.


This may help:

Also Danny’s slides from the workshop the other week:

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Looking at your list SDR is mostly used for “Software Defined Radio”, but like most TLA’s/ETLA’s context is critical to the actual meaning. And LO is used in the RF world to mean “Local Oscillator”.

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Yes, I’ve read the datasheet a few times … but the workshop files … very cool … Exactly what I need … Should keep me busy for a few days :heart_eyes:

Today I am now approx. 10 times more knowledgeable about how the LimeSDR works than I was yesterday and possibly 1/100 the of the way to complete mastery of this gadget :sunglasses:

I found this video by Ettus Research which explains the how and why of putting together an FM radio on GNU radio which looks quite informative: CLICKY LINK. Should help fill in a few of the many blanks in my knowledge.

I’ll follow the tutorial step by step. Obviously the initial block will be different. Also, I wonder what to type into the antenna option box? RX1_L? I guess I’ll find that info in the soapy driver files unless someone knows it already?

Someday, hopefully sometime within the next ten years, I’ll be able to write tutorials like this myself!

Haha, no way to understand it all at once. Yes I put some time, here and there, into RF then do other life stuff. Some people call it cross-training I think.

OIP3: Output Third-Order Intercept Point

A new’n:
TDOA: Time Difference On Arrival

That’s the same one I watched a while ago (and linked to in that other thread on FM flowgraph). Useful video.

One caveat… GRC (new acronym! Gnuradio Companion) seems to be leaning more toward Qt now but I’m not sure what that really means.
Maybe they don’t support the WxWidgets anymore???

I’ll follow the tutorial step by step. Obviously the initial block will be different. Also, I wonder what to type into the antenna option box? RX1_L? I guess I’ll find that info in the soapy driver files unless someone knows it already?[/quote]

LNAL for example. You can specify the channel too but I recall that SoapySDR can’t tune other channels. I might misremember that though. Search in this site, it’s been discussed.

In 10 years we will just use voice commands.

  • Tune 1.09 gigahertz
  • Sample 2e6
  • Demodulate
  • Decode
  • Output to 109g.dat

FWIW here’s what I added to my dictionary db:

“Can also mean Direct Current and can mean 0Hz as-in DC-6GHz or 0Hz-6GHz”

I’ve got this weird idea in my mind about creating an Arduino based ‘box’ which controls the LMS7002M via a vast array of user programmable knobs and toggle switches with a Steam Punk décor. I should draw up a 3D cad sketch.

That I’d like to see. Maybe repurpose one of those massive sound studio mixing boards. They are vast. Nice to also have sound effects on the sliders/knobs and maybe a computer voice feedback ala Star Trek. Or HAL9000. And one knob that goes to 11.

"I'm sorry Tegwyn I cannot let you do that, you might send tx voltage out through rx1 and destroy your LimeSDR."

How to know when AGC means automatic gain control or adaptive gain control? Or are they essentially the same thing?

I think you’ll find it means the same thing.

Just wanted to say thanks for this. I still have to look at it, but I at least cloned it.

Another one that’s a little fuzzy. I see things like 65MHz sample rate. Is 65Msps(or 65Ms/s, i.e. 65 million samples per second) equivalent or is the writer trying to impart some other info?

Andrew, thank you for sharing workshop materials! Is video from sessions available?

Hi Roman, it is not as yet. The quality didn’t turn out so good and there are plans to re-record the presentations in more of a controlled environment.

Nyquist Frequency is used in LimeSuiteGui. I read the definition but confused on what to enter. This is in the FFT viewer of LimeSuiteGui.

If I want 1GHz what do I enter in this field?