2 meter ssb is alive and well

[kg4kww]

Tonight wed 3/30/05 the band opened and I was able to make contact with a station in Frisco NC on Hatteras Island.

Tropo for thursday is looking to be pretty good up and down the US East Coast. So, come on guys, lets fire up that 2 meter ssb gear and make some QSO's.

[KM5FL]

2 meters down here has been open the past several nights up into the wee hours of the morning. I've made contacts in FL, MS, GA, AL, OK, CO, and TX Panhandle....

KM5FL

[kg4kww]

OK, dude, keep it up. Keep the 2 meter ssb spirit alive. Come on guys, fire up that all mode VHF / UHF gear and make some contacts the old fashion way. That's to say, work for them.

[ac3p]

I hope to get my antenna up to a decent hieght this spring and do sime 2 meter SSB.

I have been thinking about SSB and ECOMMs. Sure everyone is tied to FM and HT's but recently one of the local EOCs put in a new pager system and it's tearing up the reception on FM.

I wonder how SSB would fair against the pagers. Would the receiver bandwidth be narrow enough to filter out the RFI from the pagers?

I am thinking of running some tests but if anyone knows. I would like to know.

73

[KM5FL]

Quote[/b] (ac3p @ Mar. 31 2005,12:48)]I have been thinking about SSB and ECOMMs. Sure everyone is tied to FM and HT's but recently one of the local EOCs put in a new pager system and it's tearing up the reception on FM.

I wonder how SSB would fair against the pagers. Would the receiver bandwidth be narrow enough to filter out the RFI from the pagers?

I am thinking of running some tests but if anyone knows. I would like to know.

73
Problems from pager interference is usually due to the proximity of the pager system antennas to the 2 meter repeater antennas.

In "FM jargon", 2 meter SSB is simplex operation, no repeaters or HTs are involved.. Antenna polarity is horizontal..

My 2 meter SSB antenna is located at the top of a 100 ft tower and fed with 7/8" Andrews Heliax. I very seldom encounter (or produce) any interference.

I'm not sure of what "tests" you're referring to. I'm not aware of anyone who has conducted tests involving 2 meter SSB/pager interference. I don't think it's feasible for you to install a 2 meter SSB antenna at a repeater site.. A small low gain antenna on a 20 foot pole would not do the "test" justice.

KM5FL

[kg4kww]

Folks I was able tonight (3/31/05) to make contact with a station in EM73 from FM17 on 144.200. Not bad, not bad at all. The tropo has been in and out tonight (3/31/05) to say the least. I will be glad when the tropo gets better.

Hope you all can do the same on 2meter ssb.

73

[ac3p]

What I was refering to was a ECOMM exercise that was done without repeaters.

The pagers were desensing the HTs and mobile rigs in the area.

I thought that using a narrower bandwith mode and horizontal polarization might make a difference.

I know that everbody is using FM and repeaters for emergency nets but this exercise was designed to see if communications could be maintained without the repeaters.

The test I have in mind is to set up an SSB station with a portable 3 element beam on a 20 ft. temporary mast near the EOC and see communications can be maintained while the pager site is transmitting.

73

[kf6rdn]

I know most run simplex/weak single stuff horizontal. But given the number of these new radios, icom 706 and their ilk, why not more vertical or mobile ssb work?

It's very hard to drive your car vertically.

[ac3p]

Those 2 meter 1/2 wave loops are small enough to be mag-mounted.

Way back when I used to run a 6 meter squalo on the car roof with suction cups for AM moblie.

There's nothing saying you can't run vertical on SSB. I do I all the time on HF.

The real problem with the test is that most hams don't have 706's or comparable rigs on two meters. Wouldn't be great if ICOM or Yeasu or Kenwood would come out with an all-mode HT? #I guess the the closest rig to that would be the FT817.

I think I am talking myself into getting one. HMMMM. Timonium Hamfest tomorrow. # #http://www.qrz.com/iB_html/non-cgi/emoticons/smile.gif

[ac3p]

KWW -

When are you usually on 144.200 mhz. ?

Maybe if the condx are right there may be a path to Baltimore sometime.

73

[KM5FL]

One of the reasons for using horizontal polarization is because most interference (power lines, pagers, etc) is vertically polarized.. The interference is attenuated by approximately 20dB.. That's a pretty good "head start" on defeating interference.

3p:
I'm interested in the results of your tests. Keep us posted on your progress..

KM5FL

[kb2vxa]

Hi guys,

You'll get the same problems from a nearby pager on SSB as you do on FM but probably won't recognize the intermod but you'll surely notice the sudden loss of signal due to desense. There's an easy fix to it all, the 2M helical bandpass filter from DCI, mine worked well a block away from a 250W pager although I don't need it here. It stopped a nest of pagers and other commercial transmitters dead in their tracks a couple of times hilltopping in the mobile.

Horizontal polarization won't matter for beans when the signal from a strong local source is involved. As for using vertical for SSB, it's all I have and the loss is enough to kill all but the strongest signals and they're hard to copy at that. It would be nice if more hams used vertical, I'm not the only one, I have QSOed with a few but the key word here is "few".

Speaking of halos and squalos, if I can see myself clear this summer a 2 stack is going up on the existing mast. Why 2? Because one has negative gain of 0.4PF (power factor) so two are needed to aproach unity.

You guys in 4 and 5 land will have to wait for 2 land to catch up to your weather conditions, we're barely out of the winter doldrums here at the Jersey Shore. When it opens LOOK OUT and switch in your attenuators, our coastal ducting is legendary. Well, better luck this year, no appreciable inversions for the past 2 years thanks to odd weather conditions.

[kb2vxa]

Hi 5FL and all,

"One of the reasons for using horizontal polarization is because most interference (power lines, pagers, etc) is vertically polarized.. The interference is attenuated by approximately 20dB.. That's a pretty good "head start" on defeating interference."

While that may be true for HF it just ain't so on VHF where noise is practically nonexistant. I used AM a while back and it's so quiet you can hear that famous pin drop. Verical or horizontal still no noise.

In the very early days experimenting with VHF broadcasting, TV engineers chose horizontal polarization because it's range is greater than vertical. Don't ask, I don't know why but it's true, a proven fact. Horizontal was the norm and still is but when vehicles were outfitted with VHF radios it became clear that unwieldly horizontal antennas would rather be vertical whips. It's been that way for mobiles from the beginning and shal remain so for antenna considerations.

Point to point comms and broadcasting for the longest time was the norm until a vertical component was added to FM signals when FM car radios became popular, vertical antennas again. With modern development of pylon and other VHF/UHF antenna designs TV and FM signals are often circularly polarized so it makes no difference which way the monopole on the TV or FM "boom box" is oriented.

Well folks, there's a brief history so now you know why mobiles are vertical and everything else is horizontal be it omni or beamed.

[WB2WIK]

Quote[/b] (kb2vxa @ April 01 2005,14:07)]While that may be true for HF it just ain't so on VHF where noise is practically nonexistant. I used AM a while back and it's so quiet you can hear that famous pin drop. Verical or horizontal still no noise.

In the very early days experimenting with VHF broadcasting, TV engineers chose horizontal polarization because it's range is greater than vertical. Don't ask, I don't know why but it's true, a proven fact. Horizontal was the norm and still is but when vehicles were outfitted with VHF radios it became clear that unwieldly horizontal antennas would rather be vertical whips. It's been that way for mobiles from the beginning and shal remain so for antenna considerations.
VXA's mostly right.

"Noise" on VHF is miniscule compared with HF, and this is why RF stage noise figures start to become important above 144 MHz. However, if you can plug in your antenna and not hear an increase in noise, even on VHF or UHF, that means either or both of two things:

1. Your antenna isn't big enough to actually capture sun noise;

2. Your front end sensitivity isn't very good, and noise figure is higher than ambient (mostly solar influenced) noise, so therefore you can't hear it.

Since most all modern VHF-UHF gear has plenty of sensitivity unless it's defective, I'd vote for "1" most of the time.

I can always hear an increase in noise level when I plug in an antenna on 2 meters, using a linear detector (like AM-SSB-CW). It's substantial. If I aim my beam towards the sun (like east at sunrise, or west at sunset), the increase is substantial -- a few "S" units worth. But I'm using large beams on a tower, with hardline. If I plug in a vertical omni like an "FM stick," this doesn't happen.

About horizontal polarization, the data goes way back to the 1930s and was well reported in the RCA Broadcast Engineering journals, which I've seen many times and have some old photocopies (no originals) of. The earliest broadcast TV experiments pre-date the Empire State Building, and were done from other high locations, but then mostly repeated from Empire a few years later. In every single case, horizontal polarization carried the signal over the horizon better than vertical polarization did. This is forward tropo scatter, the predominant propagation mode for VHF work over the horizon.

The standard became horizontal polarization, and still is. You won't see any vertically polarized TV antennas.

Thankfully, horizontal half-wave loops (halos, squalos, etc) for VHF are pretty small and can be easily mounted on cars and trucks. Not a easily as a whip, but not too bad. Around here, anybody who's serious about VHF SSB work from his "mobile" is using stacked loops on 2m and above, and a single halo on six meters. The difference, when working over the horizon (which from a car might mean only ten miles or so) is amazing.

WB2WIK/6

[W3MIV]

Quote[/b] (kg4kww @ Mar. 31 2005,02:23)] Tonight wed 3/30/05 the band opened and I was able to make contact with a station in Frisco NC on Hatteras Island.

Tropo for thursday is looking to be pretty good up and down the US East Coast. So, come on guys, lets fire up that 2 meter ssb gear and make some QSO's.
I wish you wouldn't shout so much.

You don't need 2m SSB. They can read your post all the way down in Frisco. Maybe even the other Frisco.