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Why not just use the internal settings, house the transmitter in a weather-proof box, and run a short wire to a 3 meter antenna?
Total posts : 45366The advantage is not in the modification but rather in the use of a base coil loaded antenna. Note that the internal inductors in the SSTRAN “load” the antenna but they are low Q.
What you suggest will work but greater range can be had with the “SSTRAN Antenna” or equivalent since the loading coil mostly cancels the very high capacitive reactance of a 3 meter radiator.
On the other hand, if all one wants to do is cover their yard and maybe those of a neighbor or two then your suggestion is workable without the fuss of the high Q loaded antenna. Having the wire antenna outdoors should help though I haven’t tried this.
Neil
Total posts : 45366Hi WDCX!
I have run my SS-Tran with it’s internal coils
in line. I have also put it at the bottom of a
9 foot pole, with a ground system, and in a water
proof box. It got out 1000 feet to the car radio.
(So this is without doing the external coil/antenna
arrangement.)I am not an electronics expert, but if you do the
mod for the external antenna with the coil, the
whole thing will just transmit farther. This is
because the big coil is more efficient than the
little one that is in the transmitter.Other people can explain this better than I can.
If you are using the internal coils, then the ground
is going to be REALLY important.
And you do have to have a good
radio on the receiving end. I guess your milage
may vary. I got 1000 feet. You might get 300
or 750, or maybe more, who knows? And it all
depends on the receiver, too. Radio can be really
weird.With the modified system in line, the RF transfer
will be more efficient, so you will get more range.
There have been many statements of coverage by
many people. As I’m sure you know, there have
been claims of 1/4 mile to 3 miles or so with the
SS Tran external antenna/coil mod.Best Wishes
Bruce, MICRO1690/1700
Total posts : 45366Concerning this statement; “If you are using the internal coils, then the ground is going to be REALLY important.” I would tend to disagree. The loss resistance of the internal loading coils will most likely dwarf the losses of all but the poorest ground system, which is to say that the the ground is probably less critical in this case. If you’re using a more efficient loading coil, then then the ground losses become a bigger factor, in which case you want to install the best ground system you can. Of course, it’s always a good idea to do that, but I don’t think you’d really see the benefit of it with the internal matching network.
I have tried this, and the results were not stellar but might cover your house and yard if you’re happy with that.
Total posts : 45366I stand corrected. Thanks for the input.
When I was 17, and studying for my first
ham license, and planning to major in engineering
when I got out of high school – I really understood
this stuff. Now I have all sorts of other stuff going
on, and things are sort of a blur. (And it’s four
decades later!)By the way, I have always liked your callsign, WEAK.
Years ago, during another Part 15 operation, I thought
of the callsign, WEEX, which is a little bit like yours.Best Wishes, Bruce, MICRO1690/1700
Total posts : 45366From What I’ve heard the Modded SSTran for use with the Antenna has range comparable to nearly equivalent or better than a Rangemaster.
Total posts : 45366weex is used and has been for a long time by an am stationon 1230 in easton pa
Total posts : 45366I enjoy hearing reports of success regarding experimentation. However, to combine previously FCC certified equipment is to completely remove the certification. This practice removes the 15.219 defense and puts your station back on the 15.209 chopping block. Personally, I don’t find that thoughtful.
Simply put, adding several feet to 100 feet of coaxial cable, the external tuning box and antenna puts the SSTran transmitter way outside its original certification. The cable length IS part of the load for the TH transmitter. I don’t understand how this transmitter got certification, but it did. So, I suggest use it as is or forget it. Using your experiment permanently might be very foolish if someone complains or the FCC finds you.
And finally, using call letters is like raising a red flag in front of a charging bull when it comes to licensed broadcasters and FCC inspectors. If you’re running a business, then do the work and apply for a license. Otherwise this is a hobby, just like Ham Radio but without the license. I guess its really more like Citizens Band. So, invent a catchy name for your listeners to identify with and don’t use call letters. Case in point, the new social media music and information sites don’t use call letters just names that listeners can identify with. They have thousands of listeners.
Folks, its a brave new world. And it will not go back to where it was years ago on our account. The genie won’t go back in the bottle.
Total posts : 45366“However, to combine previously FCC certified equipment is to completely remove the certification. This practice removes the 15.219 defense and puts your station back on the 15.209 chopping block.”
Absolutely on the first sentence, not sure I follow the second sentence, though – I don’t remember seeing anything in .219 about being limited to certified equipment.
…100mW into the final, 3 meter radiator and ground lead, total, no more than five user-built units…
Certification?
Total posts : 45366Thanks for the info. The WEEX experiment was
in 1969. It was a failed Part 15 experiment. The
transmission didn’t leave the house.
Sorry to deviate from the thread.
Best Wishes
Bruce, MICRO1690/1700
Total posts : 45366I think I understand what kk7cw is saying about 15.219 and 15.209. I interpret him as saying that the Talking House transmitter does not actually meet the letter of the law of of 15.219(b) because of the long coax of the tuning unit; but somehow it was certified anyway. Using the TH tuning unit with another transmitter does not give the user the protection of the TH certification under 15.219. In that case, Section 15.219 does not apply, and the very low Section 15.209 field strength limit must be met.
I hope I got it right.
Total posts : 45366Ermi Roos got it exactly right. Thanks for the help/
Playing with the FCC right now would not be a good idea at all. Just ask Fox TV and its affiliates if you need proof. How about the death by paper cut case of Ken Cartwright and KENC? I know there are times in Part 15 micro-broadcasting where we perceive we must pick our poison when comes to the Part 15 regulations. But, why tempt fate and the government?
I suggest we all ask, “What is the government telling us about how they want to regulate spectrum?” And then, with the answer in hand, follow their lead. The “Feed Aggregator” on this site is a very valuable tool.
Total posts : 45366Marshall commented: Simply put, adding several feet to 100 feet of coaxial cable, the external tuning box and antenna puts the SSTran transmitter way outside its original certification.
The SSTRAN transmitter is not certified but it is designed to operate under 15.219 rules which means the operator needs to adhere to the length limit for the antenna, transmission line, ground lead and input power. There are other restrictions involving out of band emissions but for now let’s let that pass. Also, I have found that the circuit modification recommended by SSTRAN for the external loading coil does not change the input power.
If I understand the comments before certification was mentioned the posters were talking about the use of an antenna with an external loading coil with the transmitter installed at the base of this coil/antenna compared to using the internal inductors in the SSTRAN. In both cases, if the transmitter is mounted at the base of the antenna then the length requirements can be met. Were we not comparing the use of an external coil with that of the internal coil and not a system comparable to the Talking House ATU approach? Since the SSTRAN is not certified, the changes recommended for using the external coil do not void the authority to operate the transmitter.
I do agree that using part of a certified system (The ATU from the TH) does not convey the certification to the modified system but it appears to me that this is not what was being discussed.
Neil
Total posts : 45366Back to the mother ship. Blog on.
Total posts : 45366Marshall,
No problem. The comments made regarding certified transmitters are correct.
The FCC Part 15.219 rules are used for certification but certification is not required for user constructed devices though these must comply with either 15.219 or 15.209. With this in mind, experimenting with user constructed transmitters is acceptable.
Neil
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