Building a hamshack/electronics lab from scratch? - Page 1
Forum section: electronics / beginners

author: fubar.gr
author_rank: Unknown
timestamp: December 16, 2014, 07:51:05 pm
content: Hi!I want to build a shack in my back yard that will serve as an electronics lab and house my radio gear.Any suggestions on materials, earthing, what to do or avoid etc are welcome!

author: VEGETA
author_rank: Super Contributor
timestamp: December 16, 2014, 07:55:44 pm
content: This will help:

author: VK5RC
author_rank: Unknown
timestamp: December 16, 2014, 10:44:14 pm
content: What areas in amateur radio are you interested? A good rf ground never goes amiss nor a tower! HiHi.

author: AG6QR
author_rank: Frequent Contributor
timestamp: December 17, 2014, 12:33:14 am
content: Agree with VK5RC. If you haven't built the shack yet, now is the time to arrange for the RF ground. A very basic intro is here:http://www.arrl.org/groundingThe RF ground topic isn't of so much interest for general electronics lab use, but if you're intending to transmit signals efficiently, it's a part of your antenna system.Speaking of antenna systems, that's something to consider early as you plan the shack. It's not a bad idea to seek the advice of a local ham club, with members who can take a look at your site in person and make suggestions appropriate to your situation.Also, consider the RF impact of each item you put into your shack. Things like switching power supplies, fluorescent lamp ballasts, computers, etc. can really mess up reception of weak signals on the ham radio bands. And unfortunately, it's difficult to determine how noisy or quiet a device is at RF without testing it yourself. If a device has an FCC id, you may be able to search the FCC site for some test results.At the very least, I'd consider having an easy way to disconnect power to all my test equipment, computers, or other potentially noisy devices. I'd like to be able to switch all the noisemakers off while operating the radio, and then perhaps switch them back on while constructing electronics devices.For ideal ham radio work, I sure wish I could have a shack far from the electrical grid, using DC batteries for power (solar charged?), with illumination provided by candles, incandescent bulbs, or LEDs running off of DC (no PWM). I sometimes operate portable from remote locations far from the electric grid, and it's amazing what you can hear when you have little or no local noise.Dave's linked video, as well as the comments of others, will cover the general electrical engineering aspects of your question well, I believe.

author: fubar.gr
author_rank: Unknown
timestamp: December 17, 2014, 07:36:32 pm
content: Thanks guys!I'm mainly interested in receiving/transmitting HF signals.I don't get what the purpose of the radials is. They are pieces of insulated wire, right? So they don't conduct in the normal sense, are they capacitively coupled to ground?

author: VK5RC
author_rank: Unknown
timestamp: December 18, 2014, 11:05:35 am
content: There are lots of good articles about the important nature of the radial network in a vertical antenna.The ARRL Handbook and its Antenna book are really good resources and include some computer modelling programs.In my simplistic thinking, I think of radials for a 1/4 wave vertical acting as a reflecting surface, turning a 1/4 wavelength vertical into a vertically oriented 1/2 wave dipole (one part of which is "below the ground")A lot of research has been done and some of the better articles I have seen are in QEX (the ARRLs experimenters journal) and if I recall correctly radials often do best mounted slightly about the ground.http://www.antennasbyn6lf.com/2012/02/elevated-radial-ground-systems-some-cautions.htmlRemember at RF frequencies just about everything capacitively couples to some degree so insulation is no barrier to RF(unless it is conductive itself e.g. a faraday cage, or coax shield). Insulation is needed to stop the copper corroding.Around my old shack I had about 6x 3 foot long copper covered steel rods driven into the earth (where they can get wet) and linked in a loop or circular manner with heavy earth cable as my RF earth. My antennas were mainly balanced types dipoles and yagis but I never had any problems with "RF in the shack" but I could turn on and off my neighbours movement detector light if I transmitted on 7MHz, so I just avoided that frequency for neighbourly relations.I would support the comment of AG6QR of getting in contact with a local radio club, often a goldmine of really practical information.