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Post by Deleted on Aug 30, 2017 1:22:49 GMT
OK, so I tested out various locations of a Talking House transmitter in my townhouse, using the wire antenna. I walked around outside with my Panasonic portable to determine the listenable range with each.
The absolute worst locations were in the middle of the house, on the top (3rd) floor. I strung the wire antenna through an 8 foot PVC pipe to get it vertical. I got maybe 100 meters before the signal faded out completely (much further on my car radio, but that wasn't the point of the testing).
The best location was simply hanging the wire antenna on the blinds covering the top floor window. Who needs an absolutely vertical antenna anyways? I was able to get 200+ meters range (I didn't go past that, as that's where Osprey Village ends), and I was also able to receive the signal (weak but listenable) around the front of the stores. But it's not practical to keep a wire antenna hanging from the blinds of my bedroom.
The next best location was hanging the wire antenna on the blinds of my office on the 1st floor. I was able to get roughly 150 meters before I wouldn't have listened to the signal, but I could hear it amongst the noise still further. Currently, I have the wire antenna going through a PVC pipe in the window frame on the 1st floor (for aesthetic reasons) and I'm getting a little less range than simply hanging the wire on the blinds (I guess the PVC is blocking the signal a bit).
My conclusions are as follows. Obviously, even though many of the building materials used in my townhouse are supposedly transparent to radio waves, enough is reflected, absorbed or attenuated to make a difference, at least for a Part 15 signal. There is certainly some metal used, in wiring, and perhaps even gyprock corners.
Locating the transmitter on the top floor made a difference, but not THAT much of a difference. In the best case scenario, apples to apples comparison, about 50 meters range. You hear stories of long radiating grounds getting people miles of range, but that certainly wasn't the case in my testing. I actually think the reason I got more range for the 3rd story installation was getting the antenna above the foliage that is directly in front of my office window (which can absorb AM signals) rather than increasing the ground length through the house wiring.
I've come to the conclusion that RSS210 (Part 15) AM is not going to do what I need it to do. RSS210 or BETS-1 FM will also not do it - I can receive the signal line of sight sufficiently far but can't hear the signal around building corners (and probably within the buildings as well).
So I'm left with looking at RSS-123, which I will do forthwith.
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Post by Deleted on Aug 30, 2017 1:42:36 GMT
Something Else To Try
In articles about HAM operators trying to do what they can from oppressive apartment locations, I've read about baseboard ground methods.
Of course the ground side of an antenna is either the negative side of a dipole antenna or the ground radials of a vertical system. As far as I know there's no advantage to combining both.
Running ground wire on the baseboard from room to room is hampered by sharp right-angle turns, but it can be somewhat beneficial as far as I've determined with in-house experiments.
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Post by thelegacy on Aug 30, 2017 17:16:13 GMT
What about carrier current AM?
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Post by mark on Aug 31, 2017 3:56:33 GMT
Interested in your findings with RSS-123 as I think that would work good for you.
Mark
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Post by Deleted on Aug 31, 2017 4:26:10 GMT
As for carrier current, it's not immediately obvious what is allowed in Canada. There is a separate document (other than RSS210 or BETS) that describes UNintentional carrier current emissions, but all they say in that document for the AM band is that the standard broadcasting rules apply.
I will bring carrier current up as well when I contact Industry Canada re RSS123.
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Post by thelegacy on Aug 31, 2017 6:55:04 GMT
Good Luck. Let us know all about RSS123 as well. It does seem though that for a short range like your talking that Carrier Current would be nice and strong and may even be city grade signal wise to Radio's in the buildings. Outside however unless the power lines are close to the receivers they may not receive the signal.
Michigan State University had a carrier current AM station way before WDBM (which is a licensed station) came on air. I didn't get a chance to hear the carrier current station though the students say it could be picked up at Flat Black And circular when the Radio was plugged in. This was a mile or so from campus.
Not too sure why they didn't keep the carrier current station for the entry level for students before letting them on the licensed station as they use to do just that before giving up the Carrier current transmitter.
I know the two had different programming as well.
It does seem as though a lot of collages have given up their carrier current transmitters. Again I don't know why.
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Post by Deleted on Aug 31, 2017 13:25:07 GMT
Why So Many College Stations Go Off the Air
A local university had a great carrier current system with transmitters in over 5 dorms which was maintained by a very skilled engineering student. When he graduated and went to work as chief engineer for a 5kW AM station in the market there was no one at the university who had a technical level understanding of running and caring for the transmitters, so it all died. The communications faculty consisted of one guy and he was teaching from out-dated books and had no engineering sense. Television was the big new thing and radio was not considered important. The same university sold its 1 kW AM station for $5,000.
A different university had a campus wide cable system with their own modulators and although it was all video, we know that FM modulators could have been added to give them both radio and TV to all dorms and buildings, but they hired a technician that didn't know what it was and the equipment ended up being junked.
A third university has a license for a legacy LPFM station put on in the 1970s which had a strong signal in a highly populated area, I used to call one of the DJ's who was a law school student who said hilarious things about politicians, but due to scarce engineering the signal has dropped into the mud and I can rarely get a whisper of a signal when a few students play records.
Academicians possibly don't make the best managers when it comes to specialized technology.
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Post by Druid Hills Radio on Aug 31, 2017 13:40:12 GMT
Why So Many College Stations Go Off the AirA local university had a great carrier current system with transmitters in over 5 dorms which was maintained by a very skilled engineering student. When he graduated and went to work as chief engineer for a 5kW AM station in the market there was no one at the university who had a technical level understanding of running and caring for the transmitters, so it all died. The communications faculty consisted of one guy and he was teaching from out-dated books and had no engineering sense. Television was the big new thing and radio was not considered important. The same university sold its 1 kW AM station for $5,000. A different university had a campus wide cable system with their own modulators and although it was all video, we know that FM modulators could have been added to give them both radio and TV to all dorms and buildings, but they hired a technician that didn't know what it was and the equipment ended up being junked. A third university has a license for a legacy LPFM station put on in the 1970s which had a strong signal in a highly populated area, I used to call one of the DJ's who was a law school student who said hilarious things about politicians, but due to scarce engineering the signal has dropped into the mud and I can rarely get a whisper of a signal when a few students play records. Academicians possibly don't make the best managers when it comes to specialized technology. Carl you hit the nail on the head. When I took some of my fellow IT guys to our transmitter site yesterday they thought the transmitter somehow amplified the audio signal so it could be heard on a FM radio.
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Post by Deleted on Sept 4, 2017 2:52:44 GMT
Grounding Will Be the Key
The most neglected part of indoor antennas tends to be the grounding, in my observed opinion.
Grounding is most important in the case of medium wave (AM) and no vertical antenna alone will be very effective without a seriously designed counterpoise.
Depending on using the ground wire in AC wiring is much over-rated by those who insist that employing it violates a rule by amounting to something of the negative side of a dipole or a "ground-lead".
The AC ground wire cannot provide an open and efficient ground circuit because it shares the walls with other criss-crossing wires and pipes which create phase cancelations by taking whatever RF is present into opposing polarity with the main ground wire. Normally one might get a slight improvement from AC ground but not enough to be of use.
In soon to come indoor antenna experiments here at KDX Worldround Radio we plan to test a few ideas for creating a useful ground plane inside the building without ripping the house apart.
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Post by Druid Hills Radio on Sept 22, 2017 13:21:09 GMT
Why So Many College Stations Go Off the Air"Academicians possibly don't make the best managers when it comes to specialized technology." Carl makes a dead on observation.
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Post by Druid Hills Radio on Oct 3, 2017 15:13:13 GMT
As for carrier current, it's not immediately obvious what is allowed in Canada. There is a separate document (other than RSS210 or BETS) that describes UNintentional carrier current emissions, but all they say in that document for the AM band is that the standard broadcasting rules apply. I will bring carrier current up as well when I contact Industry Canada re RSS123. David: Anything new on this?
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Post by Deleted on Oct 4, 2017 2:44:45 GMT
I've had some other issues that I've needed to deal with first. But I will get to it eventually.
As for the Talking House going crazy and tuning continuously, I was reluctant to do anything with it since I was returning it. What eventually happened is that the e-bay vendor I purchased it from refused to pay for return shipping as per e-bay policies, and I was refunded in full, without having to return it.
So I opened it up, tweaked a few things in the tuning section and it now seems to be working somewhat again. It won't tune in certain spots of my house, but will in others, and I'm not sure of the reasons why (unless there's metal in the walls or windows that affects the tuning), so it still may be a bit wonky. In any event, I may still play around with this, although I certainly wouldn't trust it with continuous broadcasting.
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Post by station8 on Oct 4, 2017 13:42:37 GMT
Howdy all: David c I will explain your issues and for others.
This is for the internal turner operation only!!!!! For Talking House and I.AM Radio tx.
1) You should of read your manual on the talking house or I.AM radio tx first before operation! Note: important information in manual! If you don't have a manual you should get one.
2)Here is why your tuner running continues.
A) Your Antenna is too long! Note: longer than what manufacture recommends!
B) Your receiving too much noise in through your tx antenna!
A) The fix for this is to ball up your antenna (small) place in the back right hand Side Corner by where the antenna screw into the transmitter!
B) Now let the transmitter do a recalibration this will fix your issues!
This information is in the manual.
If its not in the manual the manual could of been changed I have seen This happen.
Then you should of called the factory and asked them questions.
I have both the talking house 5.0 and the I.AM radio tx and done very long Testing with unit and mine of been good.
Personnally I did run into with the noise on my tx on a couple occasions And did what the manual said about the noise calibration and it was gone And tx tuned up great with NO issues!
I hope this helps you out
Station 8
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Post by thelegacy on Oct 4, 2017 18:39:32 GMT
In the case of My Talking House transmitter it got damaged due to being Jarred around too much and my tuner was messed up as far as the gears were concerned. Is this what you're talking about?
Just to let everyone know you want to be very careful with your talking house transmitter because that tuner section will break very easily. It has a very delicate track and if that track gets bent yes it will continuously run even if you ball your antenna up and then try to straighten it it will get stuck. So you have to be very sure to take care of that tuner.
Also if you let your transmitter sit for a long. Of time it's a good idea to get it out and operate it from time to time. Otherwise the parts can kind of dry up and get stale and when the bearings get dried up things tend to stick as well.
Not that I care one way or the other but those of you who want to go 100% buy the book if you open your transmitter and start messing around with things or changing resistors transistors and things of that nature do keep in mind that you will break the certification and your transmitter is no longer certified. So when it's inspected don't be surprised at the outcome.
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Post by Druid Hills Radio on Oct 4, 2017 19:30:54 GMT
In the case of My Talking House transmitter it got damaged due to being Jarred around too much and my tuner was messed up as far as the gears were concerned. Is this what you're talking about? Just to let everyone know you want to be very careful with your talking house transmitter because that tuner section will break very easily. It has a very delicate track and if that track gets bent yes it will continuously run even if you ball your antenna up and then try to straighten it it will get stuck. So you have to be very sure to take care of that tuner. Also if you let your transmitter sit for a long. Of time it's a good idea to get it out and operate it from time to time. Otherwise the parts can kind of dry up and get stale and when the bearings get dried up things tend to stick as well. Not that I care one way or the other but those of you who want to go 100% buy the book if you open your transmitter and start messing around with things or changing resistors transistors and things of that nature do keep in mind that you will break the certification and your transmitter is no longer certified. So when it's inspected don't be surprised at the outcome. If you replace components with the same value it will not void the certification.
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