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Some of you wanted to see the complete version, uncut, of this video in which I discuss the differences between CB and the Amateur Radio Service.  This is in response to the recent episode in which the NCIS writers missed a great opportunity to discover the vibrant reality of the current amateur radio service in the United States of America.

The previous version of the video was prematurely cut short by just over three minutes.  This version includes that ending.  I also remove some of the low-end rumblings from the vehicle.  This version should sound a little bit less annoying.  Hopefully, the quality of the video is sharper, as well.  This version was edited by Adobe Premiere CC 2017.

I appreciate the many comments, views, and shares.  Please subscribe, too!

73 from Omaha!

EDIT: Please view the NEW article, in which the FULL VERSION of this video exists.

I’ve been reading some of the chatter regarding the NCIS episode in which they incorrectly portray the amateur radio service. I thought I would make a video (vlog) and express my thoughts.

I use my new headset mic to make the video. If you have a few moments, please check it out, and let me know how the mic sounds.

Of course, share your thoughts on the NCIS thing… thanks!

https://www.youtube.com/watch?v=rv5TsoE0AZQ

Yes, the video gets prematurely cut off.  The editing software on my cell phone chopped off the ending, and I did not realize it until after it posted the video.  I’ll record a follow-up video that includes the ending thoughts, but in a new vlog edition.

Cheers and 73 de NW7US

..

I am asking for opinions on audio, in my videos. I am in the process of choosing the better of several mics. Right now, I have two comparisons. One is a lapel mic. One is a headset boom mic.

Your opinion is appreciated on the best of two microphones used in upcoming videos I hope to create on my channel on YouTube ( https://YouTube.com/NW7US ), during those times when I want to vlog from my moving vehicle.

I am assessing several things: background noise level, clarity of voice, ease of understanding my words in context to background noise, and, ease of listenability–you know, I am seeking opinions on which of the two mics makes the audio pleasant and not fatiguing.

The two videos are listed here:

http://blog.nw7us.us/post/167110007307/i-need-your-opinion-please

Please leave a comment on your preference of one or the other mic, and why.

For years now, I’ve been doing Summits On The Air (SOTA) activations using VHF and higher frequencies. The GO TO band/mode for VHF SOTA is 2-meter FM because of its overall popularity. Just about everyone has a 2m FM radio (well, almost everyone). Still, if you are on a remote peak you may not find anyone within range to work. Because of this, it really helps to optimize the performance of your portable VHF station.

Antennas

I’ve already written that the first step is to upgrade the rubber duck antenna to something that actually radiates. My measurements indicate that a half-wave antenna performs 8 to 10 dB better than your typical rubber duck. That’s a big difference. I tend to favor the collapsible half-wave antennas because they are compact and don’t require any support. Another option is the J-pole or Slim Jim antennas, typically build out of twin lead or ladder line.

The next step up is to use a small yagi antenna, such as the 3-element Arrow antenna. Although Arrow does not specific the gain of this antenna, it has been measured at the Central States VHF Society conference as having ~6 dBd of gain. I’ve been on the lookout for a higher gain antenna but I have not found one that has significantly more gain while still being backpack portable.

Modulation

Frequency Modulation performs very badly when signals are weak. The well-known threshold effect means as the signal level decreases at the receiver it simply crashes into the noise. Linear modes such as CW and SSB work much better when signals are weak, which is why they are popular with the serious VHF crowd. I’ve used my Yaesu FT-817 to make SOTA contacts on both 2m and 70cm SSB and CW. My all time best distance on 2m during a SOTA activation was 229 miles, a QSO with N7KA from Capulin Mountain using CW. However, the problem with SSB/CW is that there are much fewer radio amateurs that operate that mode. I estimate that on a typical day, there are 10 to 100 times more hams on 2m FM than are on 2m SSB/CW.

More Power on FM

I’ve noticed that I sometimes hear stations on 2m FM but they cannot hear me. Further investigation revealed that they were typically running more power than me. I had my little HT putting out 5W and they were running a 50W mobile. That got me thinking about whether I could increase my power while still having a backpack-compatible station. SOTA operation is typically QRP, around 5 or 10 W of power. However, SOTA does not specifically state a required power level…it’s really driven by the need to operate backpack portable. Hence, there are very few 1 KW amplifiers in use on SOTA summits.

Some of the Chinese manufacturers now offer compact dualband (and even quadband) VHF/UHF transceivers that output 10 to 30 watts of RF power. I purchased the Tytera MD-8600 based on my experience with other Tytera products. The radio’s specified output power is 25 watts on 2 meters. The DC power current is rated as 0.2 A on receiver and 4A on transmit, not too bad for battery operation. I paired it with a 13.2V LiFe battery rated at 4300 mAH. In theory, that would provide over an hour of transmit time or 21 hours of receive. That should be plenty for the typical SOTA activation. The size is a slightly larger than 4″ W x 1.5″ H x 5″ D and it weighs about 2 pounds. All in all, this setup is very compatible with the typical backpack portable operation.

Let’s do a little math to understand the difference in transmit signal. The TH-8600 puts out 25W compared to the 5W from FT-60. The difference in dB is 10 log (25/5) = 7 dB. Someone said to me “hey, that’s only a little more than one S unit, which is normally defined as 6 dB. Is that really enough to make a difference?” To which I responded, “yes, 7 dB can make the difference between making the radio contact or not…when signals are near the noise floor of the receiver.” For strong signals, it just doesn’t matter.

I’ve used this configuration on three SOTA activations and I like the results. On two of the activations, I compared the TH-8600 (25W) to the Yaesu FT-60 (5W) that my hiking partner (Joyce/K0JJW) was using. Both radios were connected to 1/2-wave vertical antennas, operating on 2m FM. The radios performed the same on receive, as expected. But the weaker stations we were working had trouble hearing the FT-60. Again: if signals were strong, it didn’t matter but the extra power made the difference when near the noise floor.

I checked out the basic performance of the radio on my test bench and found it to be adequate. The transmit frequency was spot on, the harmonics and spurious on 2m were about 60 dB below the carrier. The receiver sensitivity was about 0.2 microvolts. The RF output power was low, 22.4 W on 2m and 17.7W on 70cm (compared to the specs at 25W and 20W).

I was hoping the receiver performance would be better with regards to rejecting adjacent channel signals and intermodulation. I don’t have a good test bench for that but I can tell you that I noticed some unwanted interference from transmitters that were not close to my location.

How Many dB’s Is That?

So let’s summarize the dB situation.

5W HT with standard rubber duck antenna       0 dB
5W HT with 1/2-wave antenna                  +8 dB
3-element Yagi antenna (Arrow or similar)    +6 dB
25W transceiver (vs 5W output)               +7 dB

Total improvement (25W with yagi vs HT)     +21 dB

Wow, I can improve my signal strength by over 20 dB be making these improvements! I should point out that the antenna improvements help on both transmit and receive, while the increased transmit power only improves your stations transmitted signal.

73, Bob K0NR

The post More Power For VHF SOTA appeared first on The KØNR Radio Site.

Are you participating in this year’s CQ World-Wide DX Contest, either the SSB weekend (this coming weekend, October 28-29, 2017), or the CW weekend (November 25-26, 2017)?  The CQ WW is the largest Amateur Radio competition in the world. Over 35,000 participants take to the airwaves on the last weekend of October (SSB) and November (CW) with the goal of making as many contacts with as many different DXCC entities and CQ Zones as possible.

Space Weather and Radio Propagation

I have updated my forecast on the expected propagation conditions during both the SSB and CW weekends of the 2017 CQ World-Wide DX Contest.  I will publish a new update for the CW weekend, when we get closer to that November weekend.

The link to the latest update is: http://cqnewsroom.blogspot.com/2017/10/cqww-dx-contest-propagation-update.html

Good luck!

73 de NW7US dit dit

I’ve written before about how operating goals can be a good motivator for getting on the air and making ham radio contacts. It is fun to have a goal to work towards and keep checking items off on the list. A few years ago, I decided to apply this approach to Summits On The Air (SOTA). SOTA is ripe for this kind of thing, given its extensive database and tracking of QSOs.

Our family has a cabin in the mountains that we use to hike, jeep, ski, snowshore, explore, escape …  So I decided to make a list of the SOTA summits in the general vicinity of the cabin. I did not use a precise criteria, just listing the summits that seemed close by. I used the Lists Of John web site as a tracking tool. That site is used by hikers/climbers to track their ascents, often working on their own list of summits based on whatever criteria that interests them.

This list turned out to have 26 summits on it and I completed the last one a few months back, which was an unnamed peak (W0C/SP-055). Fifteen of these were the first activations of those summits. Some of these have still not been activated by anyone else (except for Joyce K0JJW, who usually hikes with me).

Now that I have completed that list, I obviously need to create a new one. With all of the SOTA summits available in Colorado, I won’t run out of options any time soon.

73, Bob K0NR

The post Twenty Six SOTA Summits appeared first on The KØNR Radio Site.

The Tytera MD-380 is an low cost radio for analog FM and DMR on the 70cm band (see video here). One of the limitations with the radio is that it only holds 1000 contacts…which seems like a lot of contacts but it fills up quickly. With DMR, each radio or user has a unique 7-digit radio ID number. For ham radio use, the DMR-MARC organization maintains a database that maps radio ID number to user name and callsign. If a user is in your contact list, the user’s name and callsign pops up in your radio’s display. Otherwise, you just see the radio ID which is not very helpful. There are over 63,000 users in the database with more being added on a daily basis.

There are a number of firmware updates to the MD380 and I have not checked them all out. I heard some guys talking about the TyMD380Tools on one of the DMR talkgroups, so I decided to give it a try. This software was developed by KG5RKI (go here) and is easily installed from Windows without a lot of messing around. This firmware upgrade loads the entire DMR-MARC database into the radio.

Now that I have the worldwide database of DMR users loaded onto the radio, its like having caller ID on my HT (see photo below). Actually, its better than that, it pulls up the other ham’s full name, callsign and location information.

This may not seem like a big deal but I’ve found it to be surprisingly useful. I am often scanning a few channels or talkgroups with my radio and just listening casually. I may not be tracking who’s talking but I can just look at the radio to see who’s on the air. It’s one of those convenience features that makes me think “why don’t all of my radios do this?”

The TyMD380Tools implements a bunch of other features but increasing the number of contacts has been the most important one for me. This is a great example of radio amateurs adapting (“hacking”) commercial gear with improvements for ham radio use. KK4VCZ, DL4YHF and others contributed to this code. Check out the software…seems to work great.

73, Bob K0NR

The post TyMD380tools for Tytera MD-380 appeared first on The KØNR Radio Site.