The “Big Test” – Results

View from WSTM tower, Syracuse NY

Another view from the tower, looking NE toward Jamesville Reservoir, Oneida, Rome, and the Adirondacks.

The test results are in, and it was an amazing success!  I sent an e-mail announcement to a number of upstate NY radio clubs, asking them to spread the word, and they certainly did!  Forty-nine hams checked in on the radio before we tuckered out after an hour and a half, and another forty e-mailed reception reports.  Many others listened but didn’t call or write, and yet others listened but didn’t hear anything.  By any measure, this is a fantastic turnout for a simplex VHF net, and I’m very grateful for everyone who participated!

Test Setup

KD2SL Test Setup

Top: Yaesu FT-857D, used for the test. Bottom: Kenwood TS-2000.

We’ll get to those reports in a moment, but first, a look at the test setup.  Other than the antenna, it was a very modest configuration.  You’ve already read about the antenna in previous posts, so I won’t cover it here.  For the radio, the original plan was to use the Kenwood TS-2000; however, some casual tests ahead of time seemed to suggest that my receive sensitivity with the TS-2000 wasn’t as good as it could be (difficulty hearing people who heard me well).  I had one other option, the Yaesu FT-857D from the car, so at literally the last minute I made the switch.

KD2SL Prototype Cavity

Prototype resonant cavity, in the foreground part of the box. It was used as a bandpass filter, protecting the receiver front end.

There are three high power transmitters on site, and another two big signals about .6 mile away.  It occurred to me, and it was suggested by others, that this large amount of RF could desense my receiver.  As it happened, I had a way to mitigate that.  Although I haven’t gotten around to writing about it yet, the duplexer is under development and I had a prototype cavity available, which I configured as a bandpass filter.  It did a great job of keeping those strong signals out of the receiver, while having minimal impact on the transmissions (about .5dB insertion loss).

In the final analysis, I’m not sure that switching receivers made any significant difference in reception quality.  A few days after the test, I had a few moments to chat with a Bill, KB2SIN from Port Crane (just east of Binghamton) and compare the receivers.  His receive level was S9+10 on the FT-857D, and S4 on the TS-2000 (preamp off), but the audio quality and background noise was essentially the same.  I know, S meters are essentially worthless for meaningful signal measurements, and their readings can be greatly skewed by receiver preamps.  In hindsight, I could have cajoled someone with a Flex to bring their rig so that I could have readings in dBm, or brought in a deluxe DX rig with a hot receiver.  However, I think it was just as legit to do the test with a common economy rig.

The Response

Signals from far and wide were heard.  In addition to the 49 contacts and 40 e-mails, I would guess that many others may have tried and failed to receive anything.  That is a tremendous response for a band that generally doesn’t see a lot of FM activity in upstate NY, compared to 80m-10m and 2m.  If I judge by the comments made by the “big test” participants, there are a lot of hams interested in 6m who have just been waiting for something different and interesting to do with it.

Here are some sample comments from the e-mail reports:

“I congratulate you on finding a use for obsolete analog TV gear.”

“This was my first 6M contact and oddly I made it from an old TV antenna…I look forward to trying your 6M repeater.”

“73 and really looking forward to the time when your repeater is up and running.”

“I enjoyed participating and hearing all the activity that you attracted.”

“I’ve never been on 6 meters before, so it was a learning experience.”

“It has been a while since I got this excited about any ham radio project. A job well done by your and your crew!”

“Thanks for bringing 6M to the Syracuse area…”

“We (all in the Elmira area that was trying to get in) were listening thru a couple 440 and 220 repeaters that had you tuned in on hill top remote bases.   Good luck with the repeater project and we are going to work on a dedicated 6 meter rig and horz. polarized antenna.”

“Hamfest season needs to get here i need a 6 meter rig!!  …i just wanted to let you know that you have me excited about 6 meters!”

“Putting a new 40′ tower up at the house, will get a 6 meter beam/or good vertical to use with your repeater.”

“You have changed the face of 6 meters.”

Comments like these are just as valuable to me as all the technical details.  It is gratifying to see so many hams getting excited about a project – learning and experimenting – and the repeater isn’t even online yet!

Signal Range

As you can imagine, anyone in Onondaga County and most adjacent counties reported full-scale, full-quieting signals, which means that basic repeater coverage in the Syracuse area will be at least as good as the better 2m and 70cm repeaters we’re accustomed to using.  However, it remained strong far beyond the typical repeater range, no doubt because of the tall antenna and lower path loss of 6m.  The most distant reception reports were around 130 miles – from Lockport (near Buffalo) to the west; Troy (east of Albany) to the east; Newburgh to the southeast; Tresckow, PA to the south (almost to Allentown, halfway into the state!); and Brighton, Ontario to the north.  With the exception of Brighton, Ontario, these were weak reception reports with QSB (fading), not actual QSOs with the test station.  It remains to be seen whether these hams will be able to work the repeater at all, or with any consistency or regularity, because the signals were pretty marginal at those extreme distances.

As you move closer to Syracuse, at distances around 75 miles (Rochester, Elmira, Binghamton, Cooperstown, east of Utica, Watertown), anyone with horizontal beams typically had very strong signal reports both directions.  Some vertical antennas also did well at that distance, but generally with somewhat lower signal levels.  By the time you move in to 40 miles, signals were consistently well over S9 both ways, no matter what the antenna.  These results pretty closely match what we expected from studying the computer generated coverage prediction.

Antennas

Antenna types used by test participants comprised just about every type imaginable: dipole, gound plane, Ringo, long wire, loop, yagi, mobile, rubber duck.  Several mentioned that the antenna was something they set up just for the test.  One of the major test objectives was to see how horizontal antennas compared to vertical, given that our repeater antenna is primarily horizontal.  There is no doubt that horizontal antennas (dipole, wire, yagi, loop) have an advantage, but every rule has its exceptions.  One contact saw a significant signal increase when he pulled his mobile’s vertical whip over to the horizontal, but yet another saw no difference when he moved the mag mount to the side of his car.  The reception in Troy, one of the farthest from Syracuse, was done using a vertical, which is not what I would have expected at that distance.  I think the lesson here is that nobody should rule out their vertical antenna, even though horizontal is preferred.

A surprising number of contacts were from hams tuning up into 80m dipoles or long wires, with excellent results from very long distances.  Maybe you don’t need to build a new antenna for 6 meters; tuning up into something you already have may do just fine!  On the other end of the scale, rubber ducks on HTs were consistently bad, even from distances that would have been no problem for 2m or 70cm.  This speaks to the very poor transmit performance (and narrow bandwidth) of rubber ducks for 6 meters, which you would expect when the antenna is so short compared to the wavelength.  If you have an HT with 6m, it will probably be useful for monitoring the repeater, but I wouldn’t expect too much on transmit.  I plan to purchase an HT with 6m, primarily so I can bring up the repeater when I’m on site doing maintenance, but I’m not expecting it to be of any use for QSOs from home (unless I connect a better antenna).

Bottom line:  Just about any antenna (except rubber ducks) will provide good service, as long as you are within an appropriate distance.  Polarity matters, but not as much as I feared.  Horizontal beams will do exceptionally well at distances not normally usable for FM repeaters; ground wave contacts from 75+ miles outside Syracuse will be common and routine.  You could have a repeater QSO between Watertown, Binghamton, Rochester, Elmira, Utica, Scranton and Syracuse!  When the band is open, much greater distances will be possible!

Repeater Personality

Every repeater has a “personality,” ranging from totally quiet to bustling drive-time.  What will this repeater’s personality be?  Not too many hams have mobile 6m rigs, so I’m guessing we’ll hear more base stations than anything else.  Since many base stations have yagis, we could have a lot of wide-area QSOs.  The novelty of the antenna on this repeater will likely generate a lot of curious traffic in the first days or weeks, but will it survive and thrive in the long run?  Will it be mostly Syracuse area hams, or have wide-area participation?  Will it replace any 2m activity, or add to it?  Will there be any regular events or nets?  It is up to YOU.  It will be what YOU make of it!

Thanks again for taking part in the test, and for your interest in this repeater.  If you haven’t yet done so, remember to subscribe or follow this blog so that you’ll get an e-mail alert with each new post.  There is a lot of information yet to be posted, about the duplexer, radio, the frequency and so on.  If all goes well, we’ll be online by mid May!

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About kd2sl

I'm a lifelong geek, interested in anything electronic, but especially ham radio, radio and TV broadcasting, and computers. Employed as a television engineer for several Syracuse, NY TV stations.
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2 Responses to The “Big Test” – Results

  1. Anya KC2ZAK says:

    That net was amazing. Any thoughts about whether the repeater will have a PL tone? If it does I’ll have to get moving to mod my rig for tones. Don’t want to miss when this goes live. 73

    • kd2sl says:

      Hello Anya! My thinking at this point is to use PL only if absolutely necessary to keep the squelch from opening when it shouldn’t. So, we’ll try it without PL first.

      73 – KD2SL

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