We're in a Golden Age for Amateur Radio • Hacker News Board

Re: We're in a Golden Age for Amateur Radio

#21

Post by resters » Wed, Nov 07, 2018, 10:43 PM UTC

jimnotgym wrote: post #20

I would like to have a go at building a receiver for listening to CW with my kids. I don't want anything on the computer, just something I can solder that will work. Is there a kit that has a good success rate? I'm in the UK if that matters.

I suggest a simple direct conversion receiver such as the really simple one in the classic book EMRFD:

https://www.amazon.com/Experimental-Methods-Design-ARRL-Inc/...

Re: We're in a Golden Age for Amateur Radio

#22

Post by kevindqc » Wed, Nov 07, 2018, 10:44 PM UTC

What is a Toroid used for and why does it need to be winded differently for different bands? Is it what generates the signals that get transmitted by the antenna?

Re: We're in a Golden Age for Amateur Radio

#23

Post by TimTheTinker » Wed, Nov 07, 2018, 10:46 PM UTC

Submission is mistitled. Should be "HF Ham Radio on a Budget".

Re: We're in a Golden Age for Amateur Radio

#24

Post by resters » Wed, Nov 07, 2018, 10:47 PM UTC

TimTheTinker wrote: post #23

Submission is mistitled. Should be "HF Ham Radio on a Budget".

The title used is more descriptive of the intent of the article, which is clear if you RTFA.

Re: We're in a Golden Age for Amateur Radio

#25

Post by SOMA_BOFH » Wed, Nov 07, 2018, 10:48 PM UTC

kevindqc wrote: post #22

What is a Toroid used for and why does it need to be winded differently for different bands? Is it what generates the signals that get transmitted by the antenna?

It's a coil when used in RF applications. Different windings give it different induction properties:

https://en.wikipedia.org/wiki/Electromagnetic_coil

Re: We're in a Golden Age for Amateur Radio

#26

Post by resters » Wed, Nov 07, 2018, 10:49 PM UTC

kevindqc wrote: post #22

What is a Toroid used for and why does it need to be winded differently for different bands? Is it what generates the signals that get transmitted by the antenna?

Ferrite and powdered iron toroids are used for winding transformers and inductors. For radio stuff they are usually used as impedance transformers or as inductors in LC bandpass filters.

Re: We're in a Golden Age for Amateur Radio

#27

Post by loph » Wed, Nov 07, 2018, 10:51 PM UTC

jpm_sd wrote: post #2

I'm almost 40 and never quite managed to get into amateur radio, but my kids are getting old enough that they might be interested. Reading articles like this gets me excited to finally give it a try.

Find a local club, there will be people there that will want to see you succeed.

Re: We're in a Golden Age for Amateur Radio

#28

Post by lightlyused » Wed, Nov 07, 2018, 10:56 PM UTC

kevindqc wrote: post #22

What is a Toroid used for and why does it need to be winded differently for different bands? Is it what generates the signals that get transmitted by the antenna?

Basically a circular inductor with a ferrite core instead of air which allows it to be more compact, have a higher inductance per volume and a greater q factor (bandwidth). A different inductance (different number of wire turns) is needed depending upon several factors, especially if you are using them to make a resonant circuit (a circuit that responds to a particular frequency). It does not generate the signal. I hope I got that right.

Re: We're in a Golden Age for Amateur Radio

#29

Post by jimmcslim » Wed, Nov 07, 2018, 10:59 PM UTC

I'm interested in amateur radio but always feel that I can't get anything done without a big honking antenna?

Re: We're in a Golden Age for Amateur Radio

#30

Post by httpz » Wed, Nov 07, 2018, 11:01 PM UTC

I have a license because my high school teacher made us do it but I never quite understood what hobbyists do with it. I see how it can be a useful skill to have for people in a certain profession but as a hobbyist what do you do? Do people just talk to random people on the radio? I'm genuinely curious.