Re: FM tuner problem

[Gary A. Edelstein]

On Wed, 09 Jul 2003 12:35:25 +1200, Gib Bogle
> wrote:

>Since my question relates to radio, there might be a more appropriate
>newsgroup, in which case I'd appreciate directions to it.
>
>I have a Fisher FM 550, which seems to be OK in terms of sound quality,
>but which has a noise problem that is really irritating. The noise is a
>buzzy crackle that comes and goes. Sometimes the sound is clean for
>many minutes, sometimes the crackle is continuous for seconds on end,
>mostly it is intermittent lasting a fraction of a second. (I'm
>referring to FM mode.) I have tried varying the tuning a couple of
>steps up and down on both sides of the station frequency, but this has
>no effect. From my general electronics experience I'm guessing that the
>noise is not caused by an electrical fault in the tuner, which seems to
>mean it is either ambient radio interference or a signal problem.
>
>I'd like advice on deciding what sort of problem I have, and also I need
>to know more about FM antennas. My house is not far from the
>transmitter (less than 20 miles) but I am located on the wrong side of a
>small hill (I can't see the transmitter, which is on top of a remote
>hill). The antenna is contained in a short plastic tube that is mounted
>on the back of the tuner. Would it help to either mount it remotely
>(e.g. in the roof space), or would I get better results with a
>different, more powerful antenna? These questions assume that my
>problem is with the signal.
>
>BTW, often (not always) bad things happen to the sound as I move around
>in the room.
>
It may be as simple as FM multipath noise due to poor reception. It
sounds like you described the AM antenna on the receiver - you may not
have an FM antenna hooked up at all, which may be the root of the
reception problems. Start out by hooking up a cheap dipole antenna to
the FM antenna connection and see if that solves it. If not, look
into something better - even TV rabbit ears can be better. The best
is a rooftop or attic FM or TV antenna, the higher the better.

Gary E

|Gary A. Edelstein
(remove NO SPAM and .invalid to reply)
|"We have met the enemy and he is us." - Walt Kelly's Pogo

[Gib Bogle]

Mark D. Zacharias wrote:

> I'm not familiar with this model, whether it's solid-state, tube, analog,
> digital.
> However, the static you mention made me think of an arcing power switch.
> Might be fine some of the time, then act up.
> Outside aerials are best, but the signal fading as you walk around the room
> has a simple cause. The radio signal bounces of your body and occasionally
> cancels the antenna signal at certain points as you move around. Just
> putting a dipole higher might help. The "short plastic tube" doesn't sound
> like any FM antenna I'm familiar with. Could it be the AM ferrite bar?

It is solid state, and the frequency selection is push-button, in fixed
increments. The plastic tube contains something connected by 4 wires -
it may well be the AM antenna (you can see I am very ignorant of these
matters). Thanks for the dipole advice.

Gib

[Gib Bogle]

Gary A. Edelstein wrote:

> On Wed, 09 Jul 2003 12:35:25 +1200, Gib Bogle
> > wrote:
>
>
>>Since my question relates to radio, there might be a more appropriate
>>newsgroup, in which case I'd appreciate directions to it.
>>
>>I have a Fisher FM 550, which seems to be OK in terms of sound quality,
>>but which has a noise problem that is really irritating. The noise is a
>>buzzy crackle that comes and goes. Sometimes the sound is clean for
>>many minutes, sometimes the crackle is continuous for seconds on end,
>>mostly it is intermittent lasting a fraction of a second. (I'm
>>referring to FM mode.) I have tried varying the tuning a couple of
>>steps up and down on both sides of the station frequency, but this has
>>no effect. From my general electronics experience I'm guessing that the
>>noise is not caused by an electrical fault in the tuner, which seems to
>>mean it is either ambient radio interference or a signal problem.
>>
>>I'd like advice on deciding what sort of problem I have, and also I need
>>to know more about FM antennas. My house is not far from the
>>transmitter (less than 20 miles) but I am located on the wrong side of a
>>small hill (I can't see the transmitter, which is on top of a remote
>>hill). The antenna is contained in a short plastic tube that is mounted
>>on the back of the tuner. Would it help to either mount it remotely
>>(e.g. in the roof space), or would I get better results with a
>>different, more powerful antenna? These questions assume that my
>>problem is with the signal.
>>
>>BTW, often (not always) bad things happen to the sound as I move around
>>in the room.
>>
>>
> It may be as simple as FM multipath noise due to poor reception. It
> sounds like you described the AM antenna on the receiver - you may not
> have an FM antenna hooked up at all, which may be the root of the
> reception problems. Start out by hooking up a cheap dipole antenna to
> the FM antenna connection and see if that solves it. If not, look
> into something better - even TV rabbit ears can be better. The best
> is a rooftop or attic FM or TV antenna, the higher the better.

I think you are right, it looks as if I do not have an FM antenna at
all. Duh. Time to explore a dipole antenna. Thanks.

Gib

[Gib Bogle]

I made myself a simple dipole antenna, and now reception is crystal clear.

Gib