• The move to the new server is done. There are some software and database maintenance updates in process. This has us passing the hat around to help out. We appreciate any donations. Seriously, even a dollar helps. The payment page may be found here - https://www.audiokarma.org/support.html

FM reception NOT antenna related.

KevinCorr

KevinCorr

Super Member
I have read the antenna threads. Great info. This is a different question.

Why is it... in layman's terms?

Your favorite station comes in great on your portable boom box (Cambridge Soundworks Bose Table radio clone) set to "internal antenna" with NO antenna connected, and on the Tivoli even in the basement with rabbit ears, and the car fm in the driveway sounds fine.

So you would think that a big good quality, dedicated stereo tuner would pick up the same stations. But nooooooooooo.
 
Register to hide this ad
either the good tuner's antenna is in a dead spot, or the good tuner needs some TLC to get back up to snuff. An out of alignment tuner will not perform well.
 
Switch your tuner to mono and see if it's reception matches your table radio. Receiving cleaning in stereo presents an added layer to over come.
 
It's all about bandwidth. Your boombox and car stereo have narrower filters in the IF which allows for lower noise reception at the expense of some distortion. The old high end tuners were designed when there were fewer FM stations and sources of interference, so the engineers designed them with wider filters for lower distortion and better sound. Some tuners have selectable IF bandwidth, so you can use a narrower filter if you have interference. Interference from a station on the same frequency but far away, can sound like distortion or noise. Likewise you can have interference from computers, modems, light fixtures, or switching supplies in a CD or DVD player. Your receiver could be located close to a source of interference.
 
gadget73 said:
either the good tuner's antenna is in a dead spot, or the good tuner needs some TLC to get back up to snuff. An out of alignment tuner will not perform well.
Click to expand...

I vote for check-out and alignment too. Any good dedicated tuner should beat most boom-boxes and car radios. Otherwise we'd have car radios in our systems!
 
Cheap radios usually have very little stereo separation, and often for weaker signals the closer to mono you are, the cleaner the sound. Tuners shoot for better SQ, including good separation and wider FR, but often require a stronger signal to get there. The more sensitive the tuner, the better for the purpose, but they aren't all created equally. As radio has continued to decline in popularity for home audio, great tuners have gotten harder to find; many HT tuner sections are just not very good, and even separate tuners are often just average. While I don't usually prefer 70s vintage audio, there is no denying the prevalence of FM as a source with the result that tuners and tuner sections of receivers were better built then, though due to age they may need experienced, professional alignment with the correct equipment, which is getting hard to find locally for many of us.
 
Wow, since I was working, a lot of good info has come in thanks.

Punker X, I have played with each tuner in every possible setting and system in the house. A fascinating field but beyond my skills and time so I will get back to you on the service when my new old tuners arrive.

I completely agree with the advice to service the tuners, gadget and ConradH.

dr*Audio and musichal, thanks for clearing up how tuners and simple radios differ. Most of mine do have switchable IF which makes the difference between no signal and mediocre....

I went tuner shopping crazy and bought up a few online. Still awaiting arrival. I will have one extra to have a sub on the bench as each goes out to the tuner clinic.

dr*Audio- your friend in Juneau was a big help pointing out that there is a hifi repair business in this state, ie Anchorage so I will try that first. He gave another lead that I have not followed up yet.

musichal- as to which tuners will be best for me, it will be a matter of experimenting. After service each can be tested with a good antenna to see if it is a keeper. On the yahoo fm group they are discussing late 80's vintage. I have a few of those on my watch list.

Two 'new' ones I will be testing soon are a Magnum Dynalab 101 and a Kenwood KT-5020. And I still have the watch list from the tuner shopping thread. Certified tuner obsession diagnosed!

Thanks for the input. I will report back after service and the better antenna.
 
KevinCorr said:
Your favorite station comes in great on your portable boom box (Cambridge Soundworks Bose Table radio clone) set to "internal antenna" with NO antenna connected,
Click to expand...

"Internal antenna" means it uses the power cord as the antenna. This is very typical on clock radios and table radios. I have only seen very few home stereo receivers or tuners which do the same thing -- most need some kind of antenna attached, even just a piece of wire a few feet long, to get reception of even strong local FM stations.
 
That Cambridge does pick up well. The Tivoli has the 'internal' switch too but needs an indoor, wire or rabbit ears.
 
You may also have a local source of interference in or near your hi-fi rig.
I had a modded DAC a while ago that was generating huge interference for any FM radio using a local indoor antenna. Turning the DAC off made the problem go away. Same for computer gear, etc. Getting 10-15 ft away from a computer can make a huge difference.

Strongly suggest you invest in a 25 or 50 ft. length of coax to move your antenna around. You may need a 300 to 75 balun at the antenna if using a folded dipole. Why not tell us what you are using for an antenna?

Also, if possible try the tuners on the upper floors of where you live. If possible, get your indoor antenna on the 2nd floor and route it to your rig through air ducts, closet ceiling, etc.

You could also have bad luck in purchases, although unlikely in hitting 3 bad in a row. My experience shows a lot of stuff that works great is kept, when it stops working great, it's sold. Not always, but more than it should happen.


KevinCorr said:
I have read the antenna threads. Great info. This is a different question.

Why is it... in layman's terms?

Your favorite station comes in great on your portable boom box (Cambridge Soundworks Bose Table radio clone) set to "internal antenna" with NO antenna connected, and on the Tivoli even in the basement with rabbit ears, and the car fm in the driveway sounds fine.

So you would think that a big good quality, dedicated stereo tuner would pick up the same stations. But nooooooooooo.
Click to expand...
 
Thanks Bob. I am tied up right now and can't play with the antenna but later summer I will install a good outdoor one for sure. When I do get the good antenna we will se if my problems are solved. I am sure I will have questions at that time.

Right now I am just getting by with trying every indoor antenna I can find.

I have a hifi set up in 5 areas, all with cd and fm and 1 with turntable. Only 1 computer in the main floor, middle with the modem right near the computer.
It is a 3 story house with a separate shop/garage about 50 feet away. All the tuners work pretty good out there but to varying degrees.
MY room is the top floor and her area is the bottom which is convenient sound separation. My now dead Rotel RT 1080 worked fabulous up there with any indoor antenna.

Right now I am working down in the bottom, off her area, replacing the heating plant as part of a whole house rebuild. I connected a radio shack Antennacraft® FMSS Omnidirectional FM Antenna to my old Rotel 990bx and hung it on the ceiling indoors. It gets 4 of 5 bars of reception with the tuner in the same room. If you move the tuner into the adjoining bedroom and leave the antenna where it is, you get only 3-4 on the reception and static.
 
KevinCorr said:
It is a 3 story house with a separate shop/garage about 50 feet away. All the tuners work pretty good out there but to varying degrees.
MY room is the top floor and her area is the bottom which is convenient sound separation. My now dead Rotel RT 1080 worked fabulous up there with any indoor antenna.

Right now I am working down in the bottom, off her area, replacing the heating plant as part of a whole house rebuild. I connected a radio shack Antennacraft® FMSS Omnidirectional FM Antenna to my old Rotel 990bx and hung it on the ceiling indoors. It gets 4 of 5 bars of reception with the tuner in the same room. If you move the tuner into the adjoining bedroom and leave the antenna where it is, you get only 3-4 on the reception and static.
Click to expand...

OK, so it's not really about the tuner after all. It's about the antenna/location, as usual, AND the antenna connection to the tuner.

Sure sounds like in your last example you are using 300 ohm flat twin lead. This type of cable needs to be twisted about every foot, and not touch anything to work OK. In reality, it is very sensitive to picking up noise unless used in very short runs. In theory it has "less loss", but the difference between it and good coax is so small in shorter runs that it's a wash.
On the other hand, coax is shielded and fairly insensitive to picking up noise.

BTW, I think those omni turnstiles are a poor choice, for many technical reasons. I would remove the connection cable hooking the 2 elements together. Use only one of the 2 omni elements, hooked to a 300/75 balun, then coax to the tuner. Turn the antenna for best reception, or try the other element for best results.
The one element you use will be omni if you turn it vertical, FYI. But you likely won't need to do that.
 
Bob@FM, do you have specific suggestions, how to hang the antenna without it touching anything? (Or were you joking?) I hadn't heard of twisting them before.
 
Bob@FM- I am using left over cable tv wire. Coaxial. I was about to go buy more and a tool and put the antenna outside. Would they have the " a 300/75 balun"?

I just happened to have that antenna because it is the only one in town. I need to order one online. Meanwhile I will try the single element. Thanks.
 
Just received a Magnum Dynalab FT101 today and stuck it in place of the Rotel 990 and it works great without playing with the antenna yet. It gets 4.5 of 5 on the reception meter. All the other switches, stereo/mono, AFC, MUTE, IF have no affect.

Yes, I will get with the antenna advice too.
 
KevinCorr said:
Bob@FM- I am using left over cable tv wire. Coaxial. I was about to go buy more and a tool and put the antenna outside. Would they have the " a 300/75 balun"?

I just happened to have that antenna because it is the only one in town. I need to order one online. Meanwhile I will try the single element. Thanks.
Click to expand...

In the USA loads of places sells 300/75 ohm baluns, and 75 ohm cable. Wallmart, Home Depot, Lowe's, Radio shack, etc. I suggest you get 75 ohm cable with ends already attached, as putting them on yourself is difficult to do correctly (and can be the reason why lots of people have problems). Usually the ground / shield connection goes bad on DIY 75 ohm connectors.
It can look like its good, but is bad. Outdoor cables can go bad after many years, the same way.

If you insist on doing F connectors DIY, get the ones that are an exact match to your cable type, are gold, and twist or screw on, NOT the ones that require clamping (unless you have a professional clamping tool, $$$).
 
Bob@FM- at Radio Shack I got a "300-ohm/75-Ohm TV Signal Combiner" that connects the coax to the antenna. I took your suggestion and connected it to only one side of that Antenna (Antennacraft® FMSS Omnidirectional FM Antenna). The MagDynFT101 pulls in a strong 4.5 of 5.

I got a second used Rotel 990bx and put it in the next room. I connected it to the same antenna with a cable coax splitter, from the antenna out to the 2 tuners.

The Rotel did nothing so I gave that up and connected the Rotel to my MagDyn style verticle 'whip' antenna and a long coax as you suggested. That tuner pulls in 5 of 5 in that room as it did up on the 3d floor.
http://magnumdynalab.com/fmantenna-st2.htm

I bought a Radio Shack crimping tool $23 for the F connectors but have only used the pre installed ends as you suggested.
Thanks for the info.
 
You must log in or register to reply here.
Back
Top Bottom