Posts Tagged ‘Tech’

Tech Day 2013 – Saturday Sept 14

Come join us on Saturday, September 14th, 2013 (9:00 AM to 2:00 PM) at the Prairie Winds Elementary School 790 Kings Deer Point East, Monument, CO for Tech Day 2013. Tech Day is for beginner to intermediate hams who want to learn more and take that ‘next step’ in ham radio.


Everyone is welcome, no registration is required. Just show up with your bright smiley face, ready to learn something and have fun.

Presentations

9:30 am – Getting started in QRP operating from Steve WGØAT of Rooster & Peanut fame [http://www.youtube.com/user/goathiker]

10:30 am – Mobile radio installation tips with James KDØMFO

11:30 am – Practical antennas made out of copper pipe by Al WBØTGE

12:30 pm - Ham Shack 101 - the basics of setting up a home station by Stu WØSTU

1:30 pm – Some Practical Antenna Theory – Bob KØNR

* Each presentation is approximately 20 minutes with Q&A at the end.

Live Demonstations

All day long, we’ll have these displays set up so you can get a hands on look at radio operating:

QRP operating, Flex Software Defined Radio (SDR), HF antennas, mobile radio installation

The local Boy Scout troop will be selling hotdogs and drinks in hamfest style.

Tech Day 2013 is proudly sponsored by the WØTLM Amateur Radio Club 

Checking Out A Baofeng UV-5RA

baofeng uv-5raIn the Winter 2013 issue of CQ VHF magazine, I wrote about some of the VHF/UHF handheld radios available from China. In that article, I reported on the measured performance of a few of the Wouxun and Baofeng transceivers. One of the Baofeng UV-5R radios that I tested showed harmonic distortion that was a bit high on the 2 Meter band, around -40 dBc.

I recently got my hands on a Baofeng UV-5RA, which is a newer version of the same radio (firmware BFB297), so I wanted to check its performance. Like the two UV-5R models I checked, the power output, transmit frequency and receiver sensitivity were all quite solid on both bands. I was more interested in the harmonic distortion present in the transmit signal.

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On the 2 Meter band, the 2nd harmonic measured -48.4 dB relative to the fundamental which is pretty good. Similar to the other radios I measured, the performance in the 70 cm band is a lot better (-56.1 dB).

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This radio has significantly better harmonic distortion than the older UV-5R radio. Of course, this is just a single sample, so performance of other radios may be different.

73, Bob K0NR

Zero Ohm Resistors

Mark Frauenfelder innocently (or cleverly) asks the question “What are zero ohm resistors for?”  on BoingBoing. The fun really starts in the comments section, with replies such as “They’re a novelty gift for electronic engineers.”

Take a look at the article here.

Yes, zero ohm resistors really do exist. Think of them as jumpers on a PC board.

73, Bob K0NR

AmateurLogic.TV 33: One Jam Packed Show

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George visits the Twit.tv studios and interviews Randy Hall, K7AGE. Tommy visits the Huntsville Hamfest. Jim builds an Audio Isolation Interface. Peter shows us the DATV QSO Party.


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