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Thinking about buying an in-line FM signal amp from Radio Shack -- see link below. I have an antenna in the attic and the radio station I like (college all jazz station) comes in pretty well, but sometimes the signal fades in and out. My FM tuner (Kenwood KT-80) and curious if this would help me in picking up this station.
Thank you.
If you want one of the best preamplifiers out there, and they ain't cheap, try an Advanced Receiver Research unit. I use them in commercial broadcast for VHF/UHF pickup as well as for FM Stereo pickup where the antenna feed is split to more than 4 receivers.
http://www.advancedreceiver.com/
Look under index of products, commercial products, receive only preamplifiers, bottom of the page - Special Frequency Ranges.
Direct link to page:
http://www.advancedreceiver.com/page12.html
The preamps are very low noise, and very linear over their working range. Narrow band preamps can also be ordered.
No affiliation. Just a very satisfied user for 20 years.
jD
If you have a ≥ 100-ft coax run, then a preamp can help. For less than 50 ft, forget it. For 50-100 ft... dunno.
Ramsey Electronics has an inline preamp kit that can get its power through the coax, which simplifies the installation. I've used an earlier version of this that worked well.
WW
There is NO substitute for the live performance.
I have got very positive results with Magnum Dynalab ST-2 FM antenna, which is connected with a nicely shielded coaxial cable solely for the tuner.However, it must be stressed that:
As indoor antenna is the only option for me and I want to have as many stations as possible, I put the ST-2 against a concrete wall facing the strongest signal direction and then amplify the signal with 205 FM Sleuth before feeding MD90. The sound quality of my tuner comes very very close to my CD sources in respect of clarity, high/low extensions, soundstage, etc.I understand not all the people are willing to pay 1600 bucks for this FM combo esp. under current situations...I don't think "pointing the antenna in the attic with a friend" is convenient, too.
If FM radio is important to you & an antenna will be your next project, it's worth to throw yourself more into it.
More experiments and more enjoyments.
Good luck,
Dan
Edits: 06/29/09
might just be a bit better than a whip.IF you had read the whole thread!? .....
Adjusting the loft antenna to that station is what he'd already done, ....
that he is thinking about getting a better yagi. And, .....
that his cable run was sufficiently lossy to make reception of the station, iffy at best. The signal amp fixed that.The MD ST-2 is a quarter wave whip and a quite poor antenna for VHF, especially for stereo FM! It has even less gain than a dipole. Yes, if you point the whip's axis at a station it is slightly directional, but it's omni pattern surrounding that axis is STILL operating so it has of necessity a rather BROAD pattern, ne cest pas!?
That it and the FM-2G by Fanfare, which I happen to know VERY well, are also overpriced when compared to the same item at a boat shop, goes without saying.
The only way to maximise the sound quality from stereo FM is to use a directional antenna with gain, and drive the front end hard into full limiting.
If you do get good results with a whip then you are lucky, but I would add that you might still very easily hear the sound quality difference from a far better antenna. A higher return on investment (ROI)!?
The issues for FM antennas start with ....
Will I need a rotator / how many directions are there on which lie stations I truly want?
Why do I hate whips? Well, I was at one time an infantryman, and did the radioman course along the way to rank. Communication during action is vital, and concentrates the mind, esp. if you have to move just a few feet to communicate/receive!
When the PBI move on foot through the bush or jungle a whip antenna, either telescopic or a bendy pack of brass strips, was a given - despite their manifest weaknesses.
I soon learned the value to all of us, of a longer wire thrown up a tree via a weight and cord, and always carried a few sets of cord, weight and wired throwing spools (like a hand-line for fishing!?). It became SOP for me that if we stopped for more than 5 minutes, OR if we needed better, I threw one up. Did I leave a good bit of wire behind? You bet.
Just as tires determine the maximum performance of a car as a system, so does the antenna set the maximum performance of a radio reception system.
If you want to be told that your whip was a good buy, you won't hear it here.
And, recommending a whip for this particular problem, while also saying how important antennas are, is quite a HOOT ;-)!
Warmest
Timbo in Oz
The Skyptical Mensurer and Audio Scrounger
And gladly would he learn and gladly teach - Chaucer. ;-)!
'Still not saluting.'
http://www.theanalogdept.com/tim_bailey.htm
Edits: 06/29/09
First, I thought I was just expressing my opinion on adding an ST-2 after buying MD 90 and 205, and "positive results" to me was the fact, mild enough(I thought?) and would not be interpreted as "a strong recommendation" nor "any superiority over the others" whatsoever.(Maybe my Chingalish was the fault:P)After reading your opinions, I have spent the last 24 yours relocating my ST-2 experimenting with various spots within my "small" apartment which is situated on the 40/F., of a condo.
These are what I've found:
1) Signal strength is not a real problem for me. Interference is.2) When locating the antenna, a concrete wall is always needed to block the western aspect in which one of the world largest container terminals is located. (I believe that is the source of interferences, though it could be wrong.)
3) A few of my favourite channels still suffer from interferences and instabilities which could be handled with by MD 205 FM Sleuth(ie. by fine-tuning a particular RF gain). But it then has to sacrifice a bit of the soundstage and high freq.extension.
4) I don't have to use RF gain mode of the 205 for most of the channels. RF Gain is only needed for the weakest channels. To bypass 205's RF gain is as simple as "one click" on its front faceplate.
Do you have any suggestions on another type of indoor antenna which is tiny enough for indoor use without much hassles? I don't mind to replace anything and report back in AA...(of course, all are subject to WAAA 2009!)
Thanks in advance for any thoughtful advices, Mr. Timbo in Oz.
And my humble apologies to anyone if misled by the posts.Best Regards
Dan
Edits: 07/01/09
Tiny antennas for FM are just NOT going to happen, the wavelength of a signal at 98Mhz is 3 metres long. But there is an antenna type that you can build for a few bucks, that for FM wavelengths can be pinned to the ceiling, or hidden under a rug, a room sized rug.Ask me via email and I will send you the "wire rhombic article" from Audio mag.
when you have read it, ...... you should be aware that it will depend on the orientation of each of your rooms two diagonals to the axes from there to the transmitters you want to receive. FM just IS directional. We can discuss, and kick it around, too. You should be able to build a couple or three pinned to your ceiling/s*. Hard to notice, or object to!
With a wire rhombic you can have very good results and if you build a couple and spread them you might be able to get most of what you want.
You do know where the transmitters you WANT are?
And, ..... given that some total weiners around here call me the antenna Nazi, you did VERY well indeed! {;-)}! I'm an Aussie, and not prone to the response that turneth away wrath.
If your wife LIKES FM, ...... an easily hidden indoor antenna - or a couple or three - that pisses all over anything else indoor, might just be saleable.
OR if she entirely HATES your hobby, you might not tell her at all, she may never look up. You're not prone to giving her one - prone - in the listening room, are yer, maaate?!
I am fortunate that my wife loves music.
Before I married her, Trisha encouraged me to 'get a moving coil', having heard a well set up* Denon 103S at a mate's place. Note that I was at the time running a Garrotted V15/III in a SME 3009/SII detachable shell arm - with MF polystyrene loading capacitors and MF 1/2 watt resistors to give the correct 47kohm/~450pf load.
* by me ;-)!
Warmest
Timbo in Oz
The Skyptical Mensurer and Audio Scrounger
And gladly would he learn and gladly teach - Chaucer. ;-)!
'Still not saluting.'
http://www.theanalogdept.com/tim_bailey.htm
Edits: 07/01/09
Only directional antennas can help eliminate interference. A rotor with a directional Yagi antenna in your attic? A preamp will only aggravate interference. No one makes a home use preamp with bandpass & narrow band notch filters. If so, entry would likely be $1K+.
seems to be too ugly for indoor use and very likely to get me divorced with my wife(which is what I don't prefer for the time being...maybe later:P).
Pls note that: all external fixtures (incl. antenna, of course)are strictly prohibited by our building management company. Antenna must fit in my small apartment.
In this case:
How about a very small satellite/disc type indoor antenna? Does anyone come across with this for FM radio?
...I have bought a new small indoor directional antenna. It proves to be much better than a whip, MD ST-2. To illustrate more sonically, when weather permits the sources are "high-rez" and the signal is strong enough, the sonic performance of my tuner comes to a par or above comparing with my CD player.
However, my learning lessons still proceed...maybe on a new project on a rhombic indoor antenna. Let's wait and see.
I have to say thank you to Timbo, the antenna nazi, for his useful information and thoughtful assistance. From now on, in my mind, when I think of Australia, the first things I have will be Tim B. and "Grange".
I assume the attic is not an occupied space. I also suspect outdoor use is restricted at your location.
FM can be a great source.
Warmest
Timbo in Oz
The Skyptical Mensurer and Audio Scrounger
And gladly would he learn and gladly teach - Chaucer. ;-)!
'Still not saluting.'
http://www.theanalogdept.com/tim_bailey.htm
The antenna really does all the work. I never had success with nominal coax runs & preamps. I have found the preamps simply increased background noise with increased signal strength. The trick is signal to noise improvements. Perhaps a hot J-Fet or even Gasfet will help with built-in banndpass filters? Who makes that?
And, I am talking about long haul open country use vs a nasty RF environment in a busy city. Its a wonder I can not light up an LED direct off of an unbalanced antenna output with one side grounded in NYC.
If you were to travel to Lodi, NJ and found WABC AM's transmitter site, you could take an 8 foot fluorescent bulb, hold it in your hand (touching ONLY the glass of the tube) and the bulb would be completely illuminated. Of course, YOU would also be exposed to this VERY high RF field. It's an "eye-popping" demonstration of just how much RF energy is radiated at an AM transmitter site like WABC's.
While the current "conventional wisdom" states that this RF field is at a low enough frequency to be "harmless" to humans, *I* wouldn't feel *completely* secure being exposed to such a field on a constant basis.
Back when technicians were manning the DEW Line in the frozen North, some technicians would stand in front of the antennas and be "warmed" by the RF radiation. (The frequencies involved are MUCH higher than AM Broadcast Band frequencies.) It was only later that some discovered they were sterile, or had a higher incidence of cancer rates. In effect, they were microwaving themselves.
I am NOT one of those people who fears cellphone use causing higher brain cancer rates. Nevertheless, I DO feel it is better to err on the side of caution whenever RF fields are involved.
Bill
Europe has stricter RF exposure standards than the US. I would not live next to a powerful AM, TV or FM broadcast station.
What about the Magnum Dynalab MD-205 Signal Sleuth FM Signal Amplifier? I have never used this unit and so I suggest you check it out. As per their web site this unit does the following:
- amplifies weak FM signals cleanly
- attenuates strong, harsh signals without coloration
- stabilizes FM antenna (and FM cable) signals
- separates interfering adjacent-station signals
- reduces multipath problems
http://www.magnumdynalab.com/md205.htm
The Magnum Dynalab MD-205 Signal Sleuth sounds interesting. If I had a better FM tuner I would probably look into it. But right now, I would rather spend the $395 on a new tuner.
Or even better, on a new roof mounted, dedicated FM antenna!
.
I will bet it won't help much and will increase noise. Of course you can return it for a refund so go ahead and try it. I think you should "repoint" the antenna for that station if you haven't already.
ET
Question "Authority", the mainstream media sucks - Go Independent and hold BOTH parties accountable instead of just the other guys!
I need music to help forget the reality of today
Thanks for the replies.DoorNail - You're right, the documentation doesn't mention FM at all. I didn't notice this. Since the Radio Shack salesman told me this is what I needed, I guess I just assumed it said "works with FM" somewhere.
TimboInOz - Yes, the antenna does point at this station. It took awhile, but I had a friend watching my tuner's signal strength meter while I was up in the attic with my compass positioning the antenna.
This evening I went back to my Radio Shack dealer and he told me I could try the signal amp for a couple of days and if it doesn't help, I could return it. So, I went for it. And, guess what. It seems to be doing the trick. Using the strength meter as my guide (this is only way I know of to measure if the signal amp helps or not), the strongest the signal ever got was 3 out of 5 bars. With the signal amp in place the signal strength reaches all 5 bars. And, the FM station does sound better with the signal amp in place than without it. With respect to noise, I don't hear any.
Sunday afternoon is my big day when I listen to my FM tuner. So, we'll see (or should I say hear) what happens tomorrow. But so far, I am pretty happy with the results.
One thing I didn't mention and I just thought about is the coax cable I used is about 2x the length I needed. I admit that I know nothing about how an antenna works, but I wonder if the cable length was causing part of my problem.
Edits: 06/20/09
It all depends upon the overall length of the coax cable and the construction of the cable itself. If we're talking a 50 foot cable, the lost is significant. If we're talking 100 feet, the loss is probably as much as you're gaining with the amplifier.
It sounds like your antenna is receiving enough signal, but it is being attenuated due to the cable itself. That's why your in-line amplifier is actually doing the job. It is taking the signal at the antenna and boosting it BEFORE it is attenuated in the coax. Since both signal and noise are attenuated in the coax, the result is a clean signal to the antenna terminals of your tuner.
Weather permitting, of course!
bill
Most antenna amplifiers tend to be noisy. I looked at the information on this amplifier and nowhere does it mention FM. Most antenna amplifiers intended for TV have an FM trap built into them. Some have a switch for the FM trap but this doesn't seem to be one of them.
ask for the old Audio mag article?! Several folk here now have copies.
Do YOU know if the existing antenna points at the relevant station now? Re-aligning it so that it still gets the others and is better at this one may be possible, if not then the biggest rhombic that can point AT that station will be best.
If the attic has fibre insulation in it, working up there needs preparation, but I can advise about even that.
;-)!
Warmest
Timbo in Oz
The Skyptical Mensurer and Audio Scrounger
And gladly would he learn and gladly teach - Chaucer. ;-)!
'Still not saluting.'
http://www.theanalogdept.com/tim_bailey.htm
They are great for taking a clean signal and boosting it, generally for use by several antennas, but they can't clean up a dirty signal nor can they put a signal where there isn't any to begin with.
I tend to think your "variable" signal is dependent on the weather or some other such outside influence so I don't think it will really help to much.
You might be better off re-orienting the antenna and/or raising it as high as possible, even if that means putting it outside.
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