Eliminating hiss from FM signal
- Thread starter jamiecantar
- Start date
Trio
Super Member
That one in your image IS an AM antenna. Fitting the reciever with an FM antenna will likely solve your issues. Worst case, if near a telephone jack, see if there is an unused pair in there. If there is, you can just a run a wire over to the unused pair and your FM performance should be magnitudes better.
jamiecantar
Well-Known Member
Thank you guys for the suggestions.
Someone also told me of this unit out there. Its more costly but may help some in remote areas.
Magnum Dynalab Singal Sleuth
http://www.magnumdynalab.com/md205.htm
and a ST-2 antenna
http://www.magnumdynalab.com/fmantenna-st2.htm
Someone also told me of this unit out there. Its more costly but may help some in remote areas.
Magnum Dynalab Singal Sleuth
http://www.magnumdynalab.com/md205.htm
and a ST-2 antenna
http://www.magnumdynalab.com/fmantenna-st2.htm
Trio
Super Member
You are close enough to enough transmitters you do not need to spend any money, or if you do, a couple bucks max. but you may have some scrap twin lead laying around ro make your own simple dipole as was shown in an earlier post. FM is line of sight, adding an amplified antenna is not going to net you anything better than a decent antenna matched to the reciever.
dr*audio
Fish fingers and custard!
You have the wrong antenna on there. Don't waste your money on something fancy, get one of these:
http://www.mcmelectronics.com/product/30-110
Markw
Super Member
Binkman
Lunatic Member
http://en.wikipedia.org/wiki/Caledon,_Ontario You can see the cnn tower in the pic.
I've made dipoles out of unused two wire insulated telephone cords, got one mounted outside right now.. it's not rocket science dude.
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kf8xo
Puts back the magic smoke
Homebrew FM Dipole
You will want to try and keep the broad side of the antenna facing towards the station your trying to receive.
You will want to try and keep the broad side of the antenna facing towards the station your trying to receive.
dr*audio
Fish fingers and custard!
Ron, we solved it. He was using an AM loop antenna on FM. I think he was too embarrassed to post the results.
Ed in Tx
Super Member
If the noise is bothersome even with a strong signal, you could pick up a Carver TX1-11 "Asymmetrical Charge Coupled FM Stereo Decoder" standalone noise reduction unit for FM Stereo. Goes in a tape loop on your receiver. They work pretty good. Was built in to Carver's TX-11 tuner. Seen these go for less than $50 on e-bay.
Catrafter has a very good suggestion. If the technical detail on the linked page is too much for your taste, here's the short version:
Lots of FM stations have added HD (digital) broadcasts between the traditional frequencies. Those can make those stations or others close in frequency hissy even on strong signals.
If it goes away in mono and you have a strong signal and it is not present on all stations, it is probably HD noise (also called IBOC). Depending on your tuner you may be SOL. KBAQ pegs the meter on every tuner I own and is still noisy. See the thread:
http://www.audiokarma.org/forums/showthread.php?t=117139
Other noise reduction options are:
Tuner with a high-blend option
Old DBX or Phase Linear Autocorrelator
Tuner with Narrow IF bandwidth (helps with HD noise)
Good luck!
Lots of FM stations have added HD (digital) broadcasts between the traditional frequencies. Those can make those stations or others close in frequency hissy even on strong signals.
If it goes away in mono and you have a strong signal and it is not present on all stations, it is probably HD noise (also called IBOC). Depending on your tuner you may be SOL. KBAQ pegs the meter on every tuner I own and is still noisy. See the thread:
http://www.audiokarma.org/forums/showthread.php?t=117139
Other noise reduction options are:
Tuner with a high-blend option
Old DBX or Phase Linear Autocorrelator
Tuner with Narrow IF bandwidth (helps with HD noise)
Good luck!
I am in Guelph (100 klms/60 miles from the 91.1 main transmitter) which is an hour's drive as the crow flies and can pick up 91.1 with only a tiny bit of hiss. I am running a 5 gang FM tuner (Technics ST-8600) with a 30 ft loop antenna. No booster used and signal strength is only 20-30 but it is still clear. My antenna is hidden under the railing of my outside deck. I also use a Heathkit AD-1304 active audio processor, which is also attached to my turntable and tape deck. The Heathkit is a little marvel and eliminates hiss, snaps, pops on just about everything. Hiss IS a problem caused by many factors and often can not be eliminated completely depending on the distance from the station.
Update: 91.1does not a super strong transmitter as I can pick up other stations transmitting from downtown TO such as Q107 with no hiss at all.
RF is black magic, it does stuff that at times that does not make any sense.
I just made these measurements, in my case. I live in Baldwin, which I would say is about the same distance as you are from these transmitters.
Based on my Si4735D60 based tuner, using a folded dipole ( on the second floor of my garage ~25 ft from the ground). I made that antenna, which is tuned to 92.3MHz, since that is the local Tx that I want to receive the best.
107.1MHz (CILQ) 24dBuV
91.1MHz (CJRT) 44dBuV
Not even close in my setup.
I can only assume it is your setup, 'with a 30 ft loop antenna, my antenna is hidden under the railing of my outside deck."
try another antenna, such as a folded di-pole, change the location, direction etc,
Is the railing made of metal?, if it is, that is a problem as well.
Why a 30ft loop?, one uses a 30ft loop for AM reception, not FM.
I just made these measurements, in my case. I live in Baldwin, which I would say is about the same distance as you are from these transmitters.
Based on my Si4735D60 based tuner, using a folded dipole ( on the second floor of my garage ~25 ft from the ground). I made that antenna, which is tuned to 92.3MHz, since that is the local Tx that I want to receive the best.
107.1MHz (CILQ) 24dBuV
91.1MHz (CJRT) 44dBuV
Not even close in my setup.
I can only assume it is your setup, 'with a 30 ft loop antenna, my antenna is hidden under the railing of my outside deck."
try another antenna, such as a folded di-pole, change the location, direction etc,
Is the railing made of metal?, if it is, that is a problem as well.
Why a 30ft loop?, one uses a 30ft loop for AM reception, not FM.
stereoguy70
Well-Known Member
Guys this is so simple it isn't funny. The issue isn't completely the type of antenna the OP was using, but the fact that ANALOG FM Stereo tuners/receivers by nature are noisy w/ hiss in stereo mode. Switch it to mono mode as others have said and the "hiss"is gone.
FM "hiss" in stereo mode is not an issue when using a DIGITAL tuner/receiver when tuned into a station. Interstation hiss when not properly tuned in on the frequency with a digital tuner is normal, same as analog, but when tuned into the frequency correctly (meaning get your 104.1 or whatever exactly on 104.1) there should be no hiss unless it is a very weak, fringe area station where it can't lock in properly to the stereo signal. (This is where digital PLL works best, much better than the older analog PLL)
If the proper antenna didn't fix it, and the hiss bugs you that much, put the receiver in mono mode and be done with it.
FM "hiss" in stereo mode is not an issue when using a DIGITAL tuner/receiver when tuned into a station. Interstation hiss when not properly tuned in on the frequency with a digital tuner is normal, same as analog, but when tuned into the frequency correctly (meaning get your 104.1 or whatever exactly on 104.1) there should be no hiss unless it is a very weak, fringe area station where it can't lock in properly to the stereo signal. (This is where digital PLL works best, much better than the older analog PLL)
If the proper antenna didn't fix it, and the hiss bugs you that much, put the receiver in mono mode and be done with it.
petehall347
the brandy coffee man
yes . if mono fixes it then try antenna and re-tuning . also consider other things like switching power supplies and tube lights and dimmers nearby etc . radio is a strange thing and all-sorts can affect it . apparently its one if them things that shouldn't really work on the grand scheme of things . like a 2 stroke engine .
