The next VOIP Topical Conference is Friday, May 4, 2012 at the Grand Sierra Resort in Reno.

Since 2001 Nevada Amateur Radio Repeaters, Inc. (NARRI) sponsored the Annual VoIP IRLP Conference that is held in the Spring. Prior to 2012 the conference was held in Las Vegas as a separate event. Now it is part of EMCOMMWEST event. Each year the meeting has broadened its scope and now includes all the major VoIP systems in use by the amateur radio community, i.e., IRLP, Echo link, EchoIRLP, All Star, D-Star and DV Dongle. Report on success of the Pacific Division D-Star Emcom Net held on Western Reflector REF014B. See the program for topical speakers.

Here is a summary of details:

•  Place: Grand Sierra Resort Conference Area
• The conference area is in the lower level – take elevator down from main floor.
• Date: Friday May 4, 2012
• Time: 9 am to Noon and 1 to 4:30 pm
• Program: elaborates on the various VoIP systems with presentations and demonstrations. See past VoIP conference session at http://www.narri.org/voip_conference.html
• Venue: 10th Annual Topical VoIP Conference
• Cost: $25 per person. No one allowed without payment, no exceptions.
• RSVP: Pre-Registration is Required by April 16, 2012.
• Registration: Not available at this time. Will begin on February 1st.
• Hotel Rooms: www.EmcommWest.org/accommodations.html

Please direct your questions to Kent W7AOR,w7aor@narri.org or phone 702-452-4412.

It is the hopes of NV Section leadership that this combo will alternate yearly between Reno and Las Vegas. Look forward to seeing you in Reno for the 10th annual VoIP Conference and EmcommWest.

This publication claims several advantages for digital communications techniques, including:

• reduced bandwidth,
• digital data transfer,
• better performance,
• immunity to interference, and
• product and system cost reduction.

It talks about some of the theory behind digital communications, explaining in relatively simple terms how the various modulation techniques work. Of course, it slams D-STAR:

Now, this method [GMSK] is considered old fashioned and no longer used by LMR [land mobile radio]. Currently, GMSK is still being used by D-STAR.

One problem I have with this publication is its implicit assumption that digital is better than analog, and that if we want to be “progressive” amateurs, we should all adopt digital communications techniques. I’m not all that convinced, and to its credit, Yaesu does concede that “analog FM can show an advantage over digital radio in some areas.”

I haven’t compared prices, but if the D-STAR radios are any indication, the prices of Yaesu’s digital radios are bound to be more expensive than the analog radios. I just don’t see that the added functionality is worth the extra cost.

What do you think? Do you think D-STAR or Yaesu’s CMF4 will gain widespread acceptance anytime soon? Do you currently own a digital radio? If not, what would convince you to buy a digital radio?

First off, I had planned to put PL-259s on the feedlines for the dipole and the VHF antenna, but when I went to do so, I found that it had already been done! That was very cool.

Next, I hooked up the Icom IC-V8000 to see what repeaters we could hit. First, I tried keying up the ARROW repeater. Nothing. Hmmmmm, I thought, maybe it’s just down. Next, I tried the U-M repeater, which is less than a mile away as the crow flies. I was able to key it, but the S-meter showed only a couple of S units. Something was wrong.

I swapped feedlines, and voila! Everything worked as I’d hoped. Somehow, we’d mis-labelled the feedlines. Not only that, there’s still nothing connected to the end of the dipole feedline, so I was actually able to key up the U-M repeater without an antenna!

Anyway, after connecting the right feedline to the radio, I chatted a bit with both Ralph, AA8RK, and Pat, W8LNO. Talking to Pat was fortuitous because he’s involved with Scouting, and when I mentioned that we planned to operate the Jamboree on the Air next weekend, he volunteered to come down and help out. That means we will be able to operate two radios, the HF station on 20m and the VHF station through the U-M repeater to EchoLink.

After that conversation, I turned the HF rig back on, and thought I’d see what was on 15 m. Tuning around, I found a small pileup on 21.017. I called up DXWatch and determined that the pileup was for T32C, the DXpedition to Chrismas Island. I accessed their record on QRZ.Com, found the bearing, swung the beam around to 260 degrees, and heard them quite well. After setting the transmit incremental tuning to about 2 kHz, I worked them on the second call! I just love that beam!

Of course, everyone and his brother jumped in with advice. Here are some of the best ones:

• Don’t be afraid to make mistakes. We were all beginners once, and we learn by trial and error.
• Hams are a forgiving bunch, especially when you’re first getting started! (Unfortunately, not all the time….Dan)
• Listen to what others are doing. Copy what’s good and avoid what doesn’t sound good to you. Ask questions.
• Check out the local ham radio clubs in your area. You can find them on the ARRL website. Find one that is fun and active with young people like yourself. (Are there any that have active young people? :) …Dan )
• Best practice is to get on the air and talk to folks. Personally, I’ve found the HT crowd to be a bit cliquish so don’t be surprised if you run into that. It isn’t that they are unfriendly, just shy.
• It would be a MISTAKE if you didn’t work a FM satellite or two with your new license! (grin) Complete, up-to-date info at … http://www.work-sat.com – you do NOT need 100W nor multiple Yagi antennas.
• Here’s a tongue in cheek article on what not to do on the radio. It’s since been quoted and reprinted all over the internet. You might want to read it to see what to avoid.

Anyone else have some advice for our new ham?

ReconRobotics Inc.'s Recon Scout

Called the Recon Scout Throwbot, the robot transmits over the 430-448 MHz portion of the 420-450 MHz frequency band, which is primarily used by the federal radiolocation service. The spectrum is also utilized by amateur radio enthusiasts. The latter group, spearheaded by the American Radio Relay League (ARRL), opposed a waiver request filed with the FCC by Recon Scout maker ReconRobotics Inc. to use the band.

The ARRL argued that ReconRobotics’ claims that the device would be useful in public safety and anti-terrorism operations didn’t prove that a waiver to use the frequency bands was in the public interest. The FCC admitted, in its order approving the waiver, that while some interference in the frequency bands may occur, it isn’t a reason to prohibit the use of the Recon Scout.

The ARRL spin on this is that this is a partial victory for amateur radio. They correctly note that the FCC granted their request for changes in the labeling and instruction manual requirements to ensure that users of the device are aware of its limitations, with regard to interference:

Recon Scout transmitters delivered after April 15, 2011 must carry the following label: “This device may not interfere with Federal or non-federal stations operating in the 420-450 MHz band and must accept any interference received.” The instruction manual must also include the following: “Although this transmitter has been approved by the Federal Communications Commission, it must accept any interference received from Federal or non-federal stations, including interference that may cause undesired operation.”

Identifying digital voice modes without digital equipment, by listening with 5 kHz analog FM receivers, isn’t easy but there are some things you can listen for. D*Star has a fairly unique sound in that every transmission begins with a short 2400 Hz tone burst; if you hear a very short “beep” at the beginning you’re hearing D*Star. MotoTRBO (which is the Motorola branded variant of ETSI DMR Tier 2) is a TDMA mode and as such it has a “sputtering” or “machine gun” sound on 5 kHz analog FM gear. Then there’s P25 Phase 1, P25 Phase 2, NDXN, etc etc. (Note: I don’t know of any amateur NXDN or P25 Phase 2 systems on the air – yet.)

To help clarify some of the current confusion, I’ve dedicated some time this weekend to generating audio recordings of various digital audio modes as received by a 5 kHz analog FM receiver. I’ve also generated spectrum plots for these modes.

Please download and play “How to Identify Digital Phone Modes on VHF/UHF” (PowerPoint 2003 format) from:

http://www.bay-net.org/articles.html

Best,

…dtw

1. The Mathematics of Mixers: Basic Principles. This tutorial walks you through the basics of mixers. Because this article is aimed at engineers, there is math involved, but it’s not overly complicated, and if you stick with it, you’ll gain a better understanding of how the mixer, one of the most basic circuits in amateur radio, works.
2. Design of Input Matching Networks for Class-E RF Power Amplifiers. The author of this article says, “Little attention is brought to the design of the input matching network and to the device bias conditions, with their effects on the overall circuit performance. This paper attempts to discuss these topics through a systematic design and simulation approach for a typical 5 watt class-E power amplifier operating at 150 MHz.”

Note that the magazine is only available as a single PDF file. To read these articles, you’ll have to download the PDF file first.

One the things I found amusing about the first part of the video is that you can see Wheelock floating around while he’s explaining how he works the pileups. When he actually does start operating, you can hear how many calls they get up there. They really have be good operators to pull the stations out of all the QRM.

Don’t believe me? Try out the FCC Spectrum Dashboard. According to this website,

The Spectrum Dashboard allows new ways for citizens to search spectrum in the United States. Use the dashboard to find out how spectrum is being used, who owns spectrum licenses around the country, and what spectrum is available in your county.

It covers the frequency range 225 MHz – 3.7 GHz, which are the frequencies generally deemed the best for wireless broadband service, and therefore, the frequencies most sought after right now.

You can do all kinds of searches, including:

• search by frequency band,
• search by service,
• search by location, and
• browse through the spectrum.

I just did a search for frequencies used by the amateur radio service and discovered that we share the 420 – 450 MHz band with the following services:

• Industrial/Business Radio Service
• Public Safety Radio Service
• Radiolocation Service

This is a great tool for any ham interested in spectrum issues.

Some guys suggested buying one of the new Chinese HTs (see right) now being sold here. They noted that for just a little more than $100, you not only get a dual-band radio, but a boatload of accessories as well.

At this point, Jeff, W8SGZ, our self-proclaimed club curmudgeon wrote:

I’ve been doing a little research.

The US “dealer” is Ed Griffin W4KMA, owner of KMA Antennas in N. Carolina (www.wouxon.us). So at least there is a US presence. The only thing that  concerns me is one little specification : spurious emission is listed as <30dB.

Part 97 says ” For a transmitter having a mean power of 25 W or less, the mean power of any spurious emission supplied to the antenna transmission line must not exceed 25 uW and must be at least 40 dB below the mean power of the fundamental emission, but need not be reduced below the power of 10 uW.” The question is, is their 30dB enough to get down to 10 uW? With only 5 W to start with, maybe it is.

The particular model in question, KG-UVD1P, is FCC “certificated” (I love that word, it’s so nonsensical) under Part 90, so it should be at least of a certain quality level. And at half the price of anything comparable from the Big 3 (or 4 if you count Alinco), it doesn’t sound bad.

Now, according to my calculations, -30 dB, only gets you down to 5 mW. To get down to 10 uW, spurious emissions would have to be -57 dB. When I replied with that information, Jeff said:

This little radio is causing me a lot more work than I like, but once I get my teeth into an investigation, I can’t seem to let it go.

Although the sales literature (what there is of it) states 30dB for spurious emissions, the User Manual states 60 dB. From what I can make out from the test reports submitted to the FCC, the actual attenuation is in the mid 20s (depending on frequency).

And most bizarre of all is this except from a letter from Wouxon to the FCC:

We would like to have the 136-174 MHz frequency range appear on the face of the FCC Grant of Certification for our Part 90 Certification. This frequency range contains frequencies regarded as usual & customary by the United States Federal Government and its various departments, user organizations and the military.

1. The applicant plans to ensure that USA users, other than those specifically identified in this letter, not operate within bands which are not allowed by the Part 90, as controlled by the users’ FCC station license.
2. This devise will not be marketed to USA users, other than those identified in the letter, namely the US Government and its various departments & military, for operation in frequency range out of Part 90.
3. The applicant acknowledges that it is a violation of FCC rules if the device operates on unauthorized frequencies

Is it just me, or does all this sound like W4KMA is in violation of FCC regulations by selling these to US hams? And are US hams who buy and use them in violation as well?

There has to be a loophole somewhere that I am missing. I mean hams are continually retuning commercial (ie Part 90) equipment to use on amateur frequencies. Why would this be any different? The applicant acknowledges that it is a violation of FCC rules if the device operates on unauthorized frequencies.

So, what do you think? It sounds to me as though the Wouxoun radios don’t meet spec and should not be allowed to be sold in the U.S.