Common Preset Radio Fault ?

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I think the answer might be " Throw it out. Buy a new one. ", but I'll ask
anyway.

I have a Sony " Mini HiFi Component System " ( what a laugh - model FH-B411
just in case ) which has a push-button preset radio as part of its features.
Last weekend without me touching anything it went to white noise on all
bands and whatever I did couldn't get it to tune anything. Its CD player and
tape deck still work, so the main power supply and amps are working I guess.

My knowledge of electronics is a shining symbol of ignorance, and radio
communications is pure black magic to me, but I know enough to be a menace
to public safety. So I took the cover off and couldn't see anything obvious
like insects or any appreciable dust build-up ( I vacuumed the boards
anyway ). The areil connections were good. The auto-tune routine goes on as
normal but it goes straight past well known frequencies and doesn't get a
hint of anything. White noise all the way. My guess is that it has a
frequency generator inside which it uses as some sort of phase-lock thingy
to tune into stations. If this is buggered then everything else is useless.

So, as this radio is 9 years old and has been on for about 15 hours a day
since new, is it likely that the silicon has simply given up ? Does anyone
out there know if this is a common fault that is fixable ?

I'm not a cheapskate, and I would happily buy a new one except this one has
' propper ' wooden speaker boxes and sounds a lot better than any new ones I
listened to.

Thanks for any help, abuse or sloppy kisses,
Dean.



Re: Common Preset Radio Fault ?


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How about this.
Take a step back in time, get a cassette tape to 3.5mm adaptor
(strathfield/dickies, five bucks in a discount bin), and hook up something
with radio reception. Cheap and effective; perhaps a line filter if you get
a lot of noise.

9 years, 15 hrs a day... Don't expect anything like that from new radios. Do
expect a radio that claims huge power, looks good, then read the specs and
find that the 400wRMS per channel is at 22% THD...

-mark



Re: Common Preset Radio Fault ?



"mark jb"
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22%  !! You could use one of those to scramble top secret military
communications.

Dean.



Re: Common Preset Radio Fault ?


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Was using my car CD player as an example... Rated to 45w/channel, at 22%THD.
Reality is you can get it up to 18 / 38 before it audibly distorts.

-mark



Re: Common Preset Radio Fault ?



"mark jb"
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Ah, interesting. I just remember seeing ads for those ' high-end ' amps
boasting about 0.001% THD. But I guess thats for HiFi wankers to worry over.
But some of the radio/CD players I listened to in the $100 to $200 range
were pretty awful. I blame iPods for dumbing down expectations.

Dean.



Re: Common Preset Radio Fault ?



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Have you accidentally knocked a Single Sideband switch or something like
that?

R




Re: Common Preset Radio Fault ?



"Roger Dewhurst"

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No. Thanks for the suggestion, but I tried tuning ' anything at all ' in to
no avail. The digital freguency readout tells me I'm on a frequency that I
know is a station, but I get SSSShhhhhh ( my impersonation of white noise ).
I might have another probe around inside soon....which sounds naughty .

Dean.



Re: Common Preset Radio Fault ?


assume the lo and the if-2nd lo is ok
as you get lots of noise and a freq display

check the rf front end / ant connections and 1st mixer

:
: "Roger Dewhurst"
:
: >
: > Have you accidentally knocked a Single Sideband switch or something
like
: > that?
: >
: > R
:
: No. Thanks for the suggestion, but I tried tuning ' anything at all '
in to
: no avail. The digital freguency readout tells me I'm on a frequency
that I
: know is a station, but I get SSSShhhhhh ( my impersonation of white
noise ).
: I might have another probe around inside soon....which sounds naughty
.
:
: Dean.
:
:


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