FM antenn***

[jerseydevil]

I am considering adding an outdoor FM antenna. The one I am looking at

specs 4 db gain. I might place the antenna indoors on an upper

floor. Does anyone have experience with these antennas? Will I

experience better performance than my indoor dipole provides,

especially if the antenna is indooors?

[Malcolm]

Well, antenna gain is usually expressed as so many dB above a dipole,

so you are looking at 4 dB better gain. That assumes your current

dipole is not amplified. Better to place the antenna outdoors

instead of in. You will generally get a stronger signal with less

multipath.

[jerseydevil]

I am looking for someone who upgraded to the better antenna

and ideally has it in the attic since that is essentially my

situation. It might be a waste if my indoor dipole works just as

well. I get fairly good FM but not absent of hissing.

Interestingly, no one seems to know much about this. Can I ask

what type of antenna you use?

[Malcolm]

I don't listen to FM much anymore, so all I currently have is an old

BIC Beam Box which is essentially an indoor electronically directable

dipole with passive circuits to tune the antenna to the frequency of

the desired station and to reject other stations. When I was

listening to FM a lot, I had an antenna about 6' long with a decent

front to back ratio and about twice the gain of what you suggest,

mounted on a mast on the roof. I was more concerned about

multipath than gain, though. If I had an outdoor antenna now, it

would probably be on a rotor.

What you need depends on a lot of things including how far you are from

the transmitters, the direction the transmitters are from you, and what

sources of multipath you have.

[PrestonTom]

Yes, Malcolm is absolutely correct. Outdoors is best.

Folks usually do this because there is a lack of sensitivity or other signals creep in (a couple of reasons for that). An indoor/amplied antenna usually is pretty ineffective.

I don't know the specifics of your situation, so take my advice with a grain of salt. What I did (I live in a semi-rural area in Southern New England) was to mount a Yagi antenna on the roof. You can get a dedicated FM one at Radio Shack. They have 2 versions. When they are on sale they are $15 & $19. Get the more expensive one. These are quite directional so you probably also need a rotator (about $35). This will give you better gain and also reject unwanted signals (same freq but but from another direction). The option of puttin it in the attic is tricky, Even though there may not be much metal in the attic (of a typical house), they do seem to work very well in practice.

Good Luck.

-Tom

[dragonfyr]

Outdoors is best - and on a rotor, with PROPER common bond grounding , although Audio Amateur did have some plans for an attic mounted antenna some years ago (...that as I recall, I never could quite figure out the plans!)

But hey, if the elements are sturdy enough, it could always double as a clothes drying rack! Or extra closet space!

But I gotta run, Tennessee is about to play Florida (boo! - damn I wish Spurrier was there to hate!), and as history is my source, UT always wins when they are the 200 point underdog and they always seem to find some novel trademarked way to lose when they are favored!!

But who cares, as the Smokies is/are the prettiest ('purtiest') place on earth!

[ka7niq]

You got your *** kicked!

I watched the whole game while listening to my Klipschorns driven by a tri path digital amp.

Now, to answer his question.

An antenna, be it dipole or Yagi, doesnt begin to show a directive pattern unless 1/2 wavelength above ground.

The more elements in an antenna, the higher the Q of the antenna, and the more it will be effected by height above ground, and proximity to nearby objects.

Radio Shack makes a crossed dipole outdoor antenna that will work just about anywhere.

If you are going to compromise a Yagi antenna by placing it in an attic, make it a small one.

A smaller antenna has a lower Q, and will be de tuned less then a higher Q antenna.

Of course, outdoors is always best, and a small yagi mounted higher will always outperform a larger one mounted closer to ground.

I like to use trees as supports by using a fishing pole to throw a sinker over the top most limb.

Then, tie a rope to the fishing line, and reel it up the tree.

Nylon ski rope works great.

Then, make you a wire dipole, and pull it up the tree!

If you only have one tree for support, the dipole can simply be made to hang vertical, or at a 45 degree angle.

A tree mounted dipole will simply amaze you!

And, you will be amazes at how many new stations are availiable once you get up about 50 feet!

Even more, if you go higher!

Multi path is also cut down, because your antenna is now free of ground clutter.

This guy http://thewireman.com/index.shtml has everything you need, and will even assemble the dipole, cheap!

Just tell him what you want to do, and he will fix you right up!

I would use coaxial cable instead of twin lead to minimize noise P/U on the line.

And yes, Ka7niq is my ham radio callsign!

[Al Klappenberger]

JerseyDevil,

In case you don't realize it "ka7nig" is an official FCC amateur radio call sign. I know becasue I have one also (I am K3KWX). We "hams" have considerable experience with radio antennas. You can beleive what he's telling you! Any antenna outside beats the tar out of any antenna inside! That's the bottom line.

Al K.

[djk]

While ka7niq is right, you don't generally build an 100Mhz antenna with wire and hoist it into a tree.

Buy one, put it on the roof with a rotator, and use a masthead amplifier to overcome loss in the line. If you only listen to one station you don't need the rotator. If you buy the longest antenna (over 6' or so) you will need the better rotator that goes in finer steps. Be sure and ground everything properly.

The BIC is great for big city use, but is worse that a simple di-pole for DX use.

The reason for noise in FM stereo is that the pilot is typically only 5% of the total power out, 95% of the power is in the mono signal.

Carver tuners have a dynamic mono blend that retains some semblance of stereo seperation at mid and low frequencies while canceling noise in the high end (by turning it into mono). A Carver with a Finco FM-5 (or similar) antenna can pull 100 miles and be quiet in stereo.

[Al Klappenberger]

Jersey...,

I have used both the Finco FM5 and the FM4. Both are excellent antennas. The FM5 is very long and may run square into the old wife acceptace factor!. I think the FM4 is the more reasonable choice. Both will require a rotator to point it at each station you listen to if you have more than one. I suspect that with the FM4 there will be lots of stations to choose from that you didn't even know where there with an indoor antenna!

Al K.

[ka7niq]

Hello Al !

The Finco is an excellent antenna.

The FM 5 used to be one of the antenna's of choice for FM DX.

Here in Florida, we get lots of Tropo and scatter modes.

I used to have the big Channel Master up!

It was mounted on top of a 72 foot Hy Gain crank up, on top of a 5 element 17 meter Monobander I built.

Because 17 meters is so narrow, we optimized the 5 element Yagi for maximum front to back ratio.

Had to give up about 1 db of gain, but it was well worth it!

Signal to noise ratio is everything.

The Computer gave it a real clean pattern with very deep side nulls, and well over 25 db over the entire band!

But, I moved, sold the tower, etc.

I am not even active anymore, the Old Kenwood TS 850 S is all thats left.

I sold the Henry 2K Ultra ... stupid me!

I bought it from the Widow of a silent key.

He was a 3 ... his name was Hans ... ex broadcast engineer for the Voice of America!

He was really in to Amtor and Pactor ... perhaps thats why he owned the big Henry ?

He also had a Kenwood TS 950 but the XYL was keeping it in case her son got his ticket ?

it's probably still there, but I really wanted the TS 850 S.

My friends up at ARRL lab test all transceivers, and the TS 850 had the best receiver of any rig ever tested by ARRL, at that time.

I bought the Henry 2K Ultra, AND the TS 850 for 1,500.00 !

I wound up trading/selling the big Henry for an Ameritron AL 1500 and a computer, and a thousand bucks!

W0AD bought it, and flew down from Minnesota to get it.

He was low band contestor, and the big Henry is still going.

What an amp!

I sold the Ameritron, and just used the TS 850 barefoot on my favorite band, 17 meters.

Gosh, it looks like there is a fair amount of us Hams here, Hi Hi !

Wil McDermott is a ham too!

I am sorta new to the world of the Heritage line of Klipsch speakers.

But, fortunately, there are many "Elmers" around here!

You, DJK, BEC,Wil, Dean, and many others,

I was about to give up on them before the tri path amp!

And, I thought the CF 4's were fussy ?

73

KA7NIQ

[ka7niq]

Here is what he need, LOL http://www.answers.com/topic/tv-fm-dx

You are so right about the BIC Beam Box.

Its great for city use.

And, its true that a push up pole/tower with a Yagi and decent rotor is best.

ALK's reccommendation of the big Finco's is a good one, the FM 5 is a "weapon of choice" among the FM dx crowd.

I am glad you added the mast mounted amplifier!

That can be very important, especially on long cable runs at VHF frequencies.

Twin Lead actually has less loss then Coax, except Hard Line of course.

The problem with twin lead is noise P/U and upsetting its balance when you come into the house.

Many Hams use Twin Lead, but go to a balun and coax cable where it enters the house.

REAL hams simply punch a hole into the side of their house, and put a PVC tube to run the twin lead into.

Of course, we have a can of Raid nearby, and own stock in Tampa Electric Company too, LOL

I used to live in Seattle, thats why I have a 7 series ham callsign.

I knew Bob and Diane Carver very well.

Seattle is a nightmare for FM reception, and I am not suprised the Carver tuner works so well!

I lived on top of one of Seattles highest hills, and I was blessed with a 120 foot tall tree in my back yard!

I had a coaxially fed vertical dipole hanging from the top mounted branch of that tree!

I had a rope coming from the bottom of the dipole, and I could actually slope it in the direction I was most interested in.

I had an Onkyo super tuner, and a Sony Es tuner too.

I could P/U Portland full quieting, and Vancouver BC !

Vancouver had a real nice Jazz station, Eh ?

Hey, BTW, have you ever tried a Tri Path amp ?

I havent hooked my Moscode 600 up yet, but this Tri Path amp I find most impressive so far.

[robster]

I had a Godar indoor antenna mounted in the attic,it did very well and was easy to psotion or aim at my favorite radio stations. But now I have a roofmounted APS 9B antenna with channel master rotator which works the very best!!

Before the Godar I had a Rat Shack Yagi antenna in the attic,it did as well as the godar but it was a absolute nightmare beyoond belief and a freakin pain to position and aim at my favorite stations. So the Godar for indoor in the attic worked best. I think there is a used Godar on Audiogon. Also www.antennaperformance.com ,makes an indoor antenna,I have no idea if it works well and the price is high. I did like the Godar,customer service with Godar is fantastic. But roofmount is the way to go!

Good Luck,

Robert

[robster]

ALSO A BIC BEAM BOX ON AUDIOGON NOW,not affialated with the seller. But Godar is very good!

[Al Klappenberger]

Ka7nig,

I have been inactive for many years exept for a 2 meter rig in my last car. I did't bother to put it in my new car, so I am totally out of the ham business. My last sereious rig was about 1973. I had a HiGain Hi-quad up about 70 feet, an ollins 75a-3 and Hallicrafters HT-32. I was running a Nation NCL2000 2 Kw linear. I was usually second or third in the DX pile-ups! I was also into RTTY. I actually liked that mode best. It all ended when a good wind storm took the quad down. I never bothered with it since! The two meter tranciever (Yeazo) is on the attic now collecting dust.

Al K.

[ka7niq]

Oh My God, a National NCL 2000!

Wow, it was designed by Maxillion in Swampscott Mass!

One of the few class ab2 linears ever made, running a pair of RCA 8122's!

Holy Cow, they are collectors pieces!

I had one, shamefully, in my CB radio days because 15 watts PEP would drive the heck out of them!

It would easily put 1500 watts PEP out!

I actually got busted out of band on CB, the Feds walked right in on me.

The XYL let em right in, thought they were her Mormon friends, LOL

They were pretty cool, and made me a deal.

Get my ham ticket in 6 months or less, and no charges.

However, they confiscated the National, and that was just as well.

I had real problems blowing Diodes in it, probably because I wasnt good at tuning it ?

I was 19 years old in 1973, into fast cars, and faster women!

Hey Al, now that I have your attention, what would be the first thing you would do to a set of AK 2 KHorns >

I think Wil suggested to first upgrade to AK 3 ?

he said it is pretty easy to do, but I dont know what to change ?

Is it just me Al, or do you hear a 'woody' coloration on some male, and even female voices ?

It sounds like it lowers Stevie Nicks voice a little bit ?

Is this a horn resonance, or is it because the woofer is playing up too high ?

Until I can sell off some stuff, I cant afford all your mods, what can I do in the meantime ?

BEC says to NOT rope caulk the horns, and I didnt like it on the CF 4's.

What are some "quick and dirty" things I can do until I sell some stuff ?

[jerseydevil]

I am considering a Winegard 4 element Yagi that I am sure you're

familiarv with. I'd be mounting the Yagi on the second story which is

of course only one flight above the ground. From what you said I would

think a very large antenna would be a waste at only this height.

The RS FM antenna is way to long for me and the APS is

right out of the question. Interference and hissing are the two current major problems.

[WMcD]

I really was not giving any advice on upgrades. Rather, I was trying to scrounge up some schematics so you can see what is going on. If anything, I was suggesting that retrograding to an A type would let you go back to basics.

People on the forum have some strong opinions on the relative sonic merits of various crossovers. I stay out of that.

I did build several AK-3 types. They're not pretty to look at but I believe the little electrons can't tell.

One design I suggest as being superior is Al K.s design. Essentailly, the midrange crossover is looking into a 10 ohm resistor (or so) plus the parallel load of the autotransformer input. You can adjust the step down function of the autotransformer as you like to vary midrange level.

The input impedance of the autotransformer does change. However, the resistor swamps out the variations. Therefore the rolloff of the crossover is not effected to any significant effect.

I have used that in a pair of my home made units.

= = = =

BTW, I'm thinking about getting back into ham radio. The Katrina situation and the general state of affairs makes me think it is almost a civic responsibility.

Unfortunately I'm in a single bedroom condo. No balcony, and no car. I'm fortunate the windows open . . . much less an attic, or a yard. I could take a QRP backpack out to the lakefront. I wonder what the cops think of a guy with a backpack with funny electronic equipment.

Best,

Gil

[Al Klappenberger]

ka7nig,

Yep! I realy like that NCL2000 amp. I even used at 100% duty cycle on RTTY. At reduced power of course. Here's a picture of the rig and of my quad antenna being cranked up.

The sound you describe is proably the squawker horn in you Khorns. The AK-3 is one of the better stock networks. I would change out the squawker horn for a set of Trachonrs first and the netwroks later.

K3KWX

alius

Al K.

[Doc Robin]

What are the surrondings like at your home? Are you in a valley surronded by hills? Or could there be large buildings around that can block the siginals. I have not played with Ham radio in about 6 years due to all of the high powered parking lot lights that have gone in in town; so much noise on the bands that i could not hear the DX anymore. These will also effect the siginal on the FM stations you are trying to receive. 73's Bill