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Does anyone else like FM?

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I thought about an amplifying antenna, but might it add noise or distortion to the audio signal?
The problem with active (amplifier) antennas is that they can amplify both signal and noise. They shouldn't add any distortion per se, though.
Some are better than others. Typically, they ain't great -- claims of their manufacturers (or distributors) notwithstanding. ;)
 
FM is free, you don't even need internet and a streamer and DAC. IMO FM tuning just works better for the user than streaming with its simplicity and quick access. When I'm listen to music I don't want to fiddle with my phone and apps. And most of the time, I like having a DJ curated playlist that just keeps the music rolling. I'm sure there are many free curated streaming music sources, but a lot of them aren't,
If I was interested in getting very high sound quality in my truck, I might be willing to pay for a top lossless quality music stream.
But I'm just not, I don't spend much time in my truck any more and a couple of my local FM country music stations sound really great to me..
I find things have changed some on the FM dial, or maybe just the stations I listen to? but maybe due to the competition from the streaming
sources, etc; they seem to have cut back on the number of, and length of advertisement commercials they play. Not too bad really IMO. ?
I also have a SanDisk Clip+ with a big memory chip in it that stores a bunch of 2ch flac's and I can load a whole bunch of albums in it, plug it into
the AUX input of my radio and let things smoke. :p
I've always loved music in my rides but for whatever reasons just never chased the HiFi demons there. For me doing that was at home where I could kick
back, maybe catch a buzz and focus on the tunes.
Each to their own. YMMV
 
I was considering going with the tv antenna like this one https://www.amazon.com/dp/B07BLNWZH...ZEZPNM5T&psc=1&ref_=list_c_wl_lv_ov_lig_dp_it for reasons you mentioned. But my old "HD tv" antenna works so poorly I'm reluctant.

What does the antenna tuning knob do, make the antenna ears act as if they are shorter/longer?
Tuning allows you peak signal gain right where you need it, and can make a noticeable difference, particularly when reception is marginal. My current FM antenna is an old Terk rabbit ears set which lacks the feature, but it's got generous 1 m long elements. Admittedly, most of my reception problems are not with signal strength, but multipath, because the antenna is pretty directional, often all I need to do is rotate it just-so.

Your current antenna would probably work great if you had a direct line of sight path to the transmitters, but then, so would pretty much any random wire.
 
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The problem with active (amplifier) antennas is that they can amplify both signal and noise. They shouldn't add any distortion per se, though.
Some are better than others. Typically, they ain't great -- claims of their manufacturers (or distributors) notwithstanding. ;)
That's what I was worried about with amplified antenna. I'm trying to reduce noise.
 
If I was interested in getting very high sound quality in my truck, I might be willing to pay for a top lossless quality music stream.
But I'm just not, I don't spend much time in my truck any more and a couple of my local FM country music stations sound really great to me..
I find things have changed some on the FM dial, or maybe just the stations I listen to? but maybe due to the competition from the streaming
sources, etc; they seem to have cut back on the number of, and length of advertisement commercials they play. Not too bad really IMO. ?
I also have a SanDisk Clip+ with a big memory chip in it that stores a bunch of 2ch flac's and I can load a whole bunch of albums in it, plug it into
the AUX input of my radio and let things smoke. :p
I've always loved music in my rides but for whatever reasons just never chased the HiFi demons there. For me doing that was at home where I could kick
back, maybe catch a buzz and focus on the tunes.
Each to their own. YMMV
I agree. It seems like there's less commercials and less annoying DJ talking and personalities on FM now than there was back in FM's hey days.

I'm the same way with car audio. I've accepted that it's just not the place to have high sound quality really. There's all kinds of background noise, space and access limitations for electronics and for speakers, and with late model vehicles it's very difficult to add things to the electrical system with it being networked, power from the battery/generator is limited etc. Plus factory car sound systems aren't as atrocious as they use to be and sound about as good as most aftermarket audio.
 
Tuning allows you peak signal gain right where you need it, and can make a noticeable difference, particularly when reception is marginal. My current FM antenna is an old Terk rabbit ears set which lacks the feature, but it's got generous 1 m long elements. Admittedly, most of my reception problems are not with signal strength, but multipath, because the antenna is pretty directional, often all I need to do is rotate it just-so.

Your current antenna would probably work great if you had a direct line of sight path to the transmitters, but then, so would pretty much any random wire.

Rabbit ears with a tuning knob sounds like a good solution. I wonder if my reception problems are multipath and not signal strength too. Most of the stations aren't that far away and some are high power and it's like certain times of the day I get more noise.

One thing's got me confused is the recommended dipole length for the middle of FM is 5-6 inch and it's recommended it be horizontal. So for VHF which I think would be similar but higher frequency and shorter dipole length why are rabbit ears , and actually other FM antennas too, adjustable to be so long and mostly vertical? I think with most of my FM stations mostly north and south of me, I'd want to face the dipole antenna N-S and the poles E-W.
 
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No, not 5 to 6 inches. The (full) wavelength at 98 MHz (midband) is 120.4 inches. 1/2 wavelength is 60.2 inches and 1/4 wavelength is 30.1 inches (you know, roughly ;)).

1737725310615.png


The horizontal orientation assumes horizontal polarization of the signal, but I think (?!?) that many FM stations transmit a circularly polarized signal.
You want the long axis of the dipole "across" the signal. If the signal is to east or the west, you want the "ends" of the T facing north-south. Whether horizontal or vertical is better really should be determined empirically.
Since the wavelengths for FM are relatively short (it's all relative! AM radio wavelengths are on the order of 483 feet at 1000 kHz), small shifts in position can have substantial impact on reception.
 
My problem with FM is the advertisements and mindless talkback "personalities". It's unlistenable in this country because of that, and I have some lovely tuners too, so a pity.

Too much of FM is like this:

When I listen to FM it is typically NPR. I haven't regularly used FM for music since the 80's. SoCal had some great radio stations.

Martin
 
1737727466365.gif



The dipole's a balanced antenna. Note that the characteristic impedance depends on the mode of construction. A 'folded dipole' is 300 ohm; a 'straight' dipole is 75 ohm.
 
@ Mark1 -- apologies if this is all familiar to you!
Multipath. FM radio signals behave more like light than do, e.g., AM radio signals. To wit, reception is typically line of sight -- if your antenna cannot see (so to speak) the transmitting antenna, it won't be able to pick up the transmitted signal. On the other hand, terrain, or a passing car or airplane or even person in between transmitter and receiver can bounce the signal around an obstacle -- when there's more than one path from transmitter to receiver, there are issues with phase -- that's "multipath". In the days of analog TV, multipath revealed itself as "ghosts" on the video image. On FM radio the effects are sometimes more subtle -- except :) when the source of the bounced signal is something like a passing airplane; then one gets a nice sort of Doppler effect. :)

Using a took like FM Fool https://www.fmfool.com/ you can see where your favorite stations' transmitters are relative to you. If there's a mountain in the way, or if it's far enough away to be "over the horizon"* -- well... that's a problem!

Don't be afraid to do some dynamic assessment of your antenna position -- although your body will influence reception if you hold a T-dipole (or any FM antenna, for that matter) and traipse around the room with it! :facepalm: Move around the room, find a likely spot, jury-rig your antenna there, go sit down and listen to the received radio result. :) Repeat as necessary. ;)
__________________
* radio transmitting antennas are usually on high towers, and/or atop mountains or tall buildings to extend the reach of the signal. :)
 
On paper, FM is excellent. In practice, if you do not have excellent reception quality, therefore with level and without any ghost image born from the reflection of waves on surrounding buildings, which means an antenna on the roof , directional and especially not in the shape of a bull's horn, vertical if the transmitter emits in vertical polarization and horizontal if it emits in horizontal polarization, and a tuner with top performance, then FM is a mediocre source qualitatively. If the tuner is vintage, you have to. also make sure that it is always well aligned...
Let's now move on to the transmission quality of the station: the rule unfortunately is "antenna processing" corrections made so that the signal occupies the maximum of the transmission power cube in order to reduce noise and nearby stations on the band that would drool over it... And to do that we do two things: dynamic compression and equalization to raise certain frequencies...
The result is designed for listening in the car...
In France, the least bad station in the FM band is France Musique in terms of signal sent to transmitters. However, it's bad: the first fortissimo passes without incident, the second just after panics the compressor and the sound suddenly recedes! When there is a soft sound after a fortissimo, or between two movements, the compressor raises the noise level and it's Niagara Falls...
DAB improved things by requiring precise levels not to be exceeded... it is therefore better than FM... which was a source much better than the LP in the 1970s when the concerts were broadcast live on the only four public stations authorized to broadcast in the FM band in France with rare other private ones! In 1981, the socialists who came to power liberalized the FM band and countless stations arrived, causing the qualitative death of FM in France...
 
We have a multipath challenge of sorts with our go-to OTA radio station: WVPR-FM Winsdor, VT, with their antenna atop nearby (but not that nearby) Mt. Ascutney. :)

Mt. Ascutney (as seen from downtown in our little hamlet)



Our little reception challenge. ;)



In full disclosure, I have a motley assortment of antennas that I use for FM in various parts of the house! In our kitchen, we have a nice, albeit unprepossessing little Sangean table radio. Sporadic issues with reception of 89.5 MHz (usually related, I think, to their output power and/or meterological conditions, or maybe the presence/absence of foliage!) have led me to use a simple but surprisingly effective monopole antenna solution (not saying that I am proud of this!).

I cut a piece of stiff, fine-gauge steel :eek: wire (like picture-frame, or baling wire) to 1/4 wavelength at 89.5 mm, shaped it into an "L" of sorts, and stuck one end into the center connection of the female "F" connector antenna jack on the radio. I stuck the long bit of the "antenna" under our kitchen window's molding trim and sill and it works... pretty well most days. It's also virtually invisible.



Here's another omni FM antenna "solution". ;) This is connected to an old Yamaha stereo receiver in our "den", for reception of that same 89.5 MHz station. In this case, it's vertically oriented... because... well, that's what I could do with it, and stay relatively unobtrusive! :p I've tried, and failed, with lots of different antennas, including amplified, compact, purpose-built FM antennas from Terk and good ol' Radio Shack, and T-dipoles, to get good reception in that room. It's an "internal" room and it contains our WiFi router :facepalm: and cable modem. It's a noisy environment. The "long" wire works well, though!
You can see the wire running along the door frame behind the little Fostex "fullrange" speaker in the photo below. The wire's held in place with a bit of BluTak adhesive "clay"! Again, not saying I am proud of this! ;)



Chance favors the prepared mind. :)

My goal here (if I have one) is to encourage you to experiment, @Mark1! Some of us find this kind of stuff fun. YMMV, though, of course. :)
Antennas are amazing. They're not magic, but their operation can seem like magic, and empiricism is essential for best results in most cases! Length is a fairly critical value -- remember that the goal is to get your receiving antenna to resonate with the transmitted radio signal that you want to receive, and to ignore absolutely all of the rest of the electromagnetic spectrum! No mean feat.
 
This thread reminded me I had this Pioneer TX-9800 tuner squirreled away in my garage. I sold it about 15 years ago on EBay and one corner of the side panel was damaged in shipping so the buyer returned it. I think I’ll hook it up to my stereo.
IMG_1300.jpeg


Martin
 
The TX-9800 ought to be pretty good qualitatively and quantitatively. :) I can't say I've ever heard/used one; I have an example of its older sibling here,though. Embarrassingly, I've never actually tried this one, either. :eek: :facepalm:

 
I have an example of its older sibling here,though.
So I'm guessing those little sliders below the tuning dials are some crude form of "preset" indicators from Pioneer ?
I don't remember ever seeing it done that way before. :p
 
So I'm guessing those little sliders below the tuning dials are some crude form of "preset" indicators from Pioneer ?
I don't remember ever seeing it done that way before. :p
even less sophisticated than that! They're just markers to guide (re) tuning to a favorite station. :) Better than the then-common hack of using a wax pencil or a Sharpie! :facepalm:
 
even less sophisticated than that! They're just markers to guide (re) tuning to a favorite station. :) Better than the then-common hack of using a wax pencil or a Sharpie! :facepalm:
LOL, The predigital tuner days, even my digital Mitsubishi didn't offer any type of presets.
But the buttons worked on my car radios going back like forever..
This 1939 Zenith has 5 presets, but that's AM only.
IMG_1820.JPG
 
No, not 5 to 6 inches. The (full) wavelength at 98 MHz (midband) is 120.4 inches. 1/2 wavelength is 60.2 inches and 1/4 wavelength is 30.1 inches (you know, roughly ;)).

View attachment 423491

The horizontal orientation assumes horizontal polarization of the signal, but I think (?!?) that many FM stations transmit a circularly polarized signal.
You want the long axis of the dipole "across" the signal. If the signal is to east or the west, you want the "ends" of the T facing north-south. Whether horizontal or vertical is better really should be determined empirically.
Since the wavelengths for FM are relatively short (it's all relative! AM radio wavelengths are on the order of 483 feet at 1000 kHz), small shifts in position can have substantial impact on reception.
View attachment 423495


The dipole's a balanced antenna. Note that the characteristic impedance depends on the mode of construction. A 'folded dipole' is 300 ohm; a 'straight' dipole is 75 ohm.
Interesting stuff. So I take it the tv rabbit ears and some FM antennas are longer because they are half wavelength, and the shorter elements of the FM antenna I ordered with 2 ~6in elements is eighth wavelength? My receiver's FM connecter is 75 ohm f-connecter, but there's a separate 300 Ohm AM, which I don't think feeds to the FM tuner. I don't

I remember now when I was a kid having a factory made FM antenna that looked like twin lead that must of been full wave dipole since it was so wide tacked on the wall near the ceiling.
 
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@ Mark1 -- apologies if this is all familiar to you!
Multipath. FM radio signals behave more like light than do, e.g., AM radio signals. To wit, reception is typically line of sight -- if your antenna cannot see (so to speak) the transmitting antenna, it won't be able to pick up the transmitted signal. On the other hand, terrain, or a passing car or airplane or even person in between transmitter and receiver can bounce the signal around an obstacle -- when there's more than one path from transmitter to receiver, there are issues with phase -- that's "multipath". In the days of analog TV, multipath revealed itself as "ghosts" on the video image. On FM radio the effects are sometimes more subtle -- except :) when the source of the bounced signal is something like a passing airplane; then one gets a nice sort of Doppler effect. :)

Using a took like FM Fool https://www.fmfool.com/ you can see where your favorite stations' transmitters are relative to you. If there's a mountain in the way, or if it's far enough away to be "over the horizon"* -- well... that's a problem!

Don't be afraid to do some dynamic assessment of your antenna position -- although your body will influence reception if you hold a T-dipole (or any FM antenna, for that matter) and traipse around the room with it! :facepalm: Move around the room, find a likely spot, jury-rig your antenna there, go sit down and listen to the received radio result. :) Repeat as necessary. ;)
__________________
* radio transmitting antennas are usually on high towers, and/or atop mountains or tall buildings to extend the reach of the signal. :)
I'm surrounded by freeways close by with plenty of semis and trucks. I wonder if that's causing multipath especially during rush hour. Otherwise the terrain is pretty flat with no really tall buildings like downtown directly in the path as far as I can tell, but probably two story houses and apartments and lots of trees :).
 
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