Whistling Dansette.....
 

Chaps,
Little Dansette Touriste car radio - circa '64, hence authentic for the old Bond Equipe.
Works ok if long aerial connected, but on car aerial or short length it whistles and howls, less so when on station but plenty on either side.
Could it be f/b through the power rails ? Should I try a few extra grounding caps for rf/if ?
Have always ignored this kind of fault before, but this set needs to work on the car aerial ofcourse !
Advice welcome Pip pip JM
PS: The set uses one of those screened & packaged mixer/tuner/demodulator units, like the radiograms, so I guess the agc circuitry is buried therein...

Re: Whistling Dansette.....
 

IF/RF stages - capacitor problems at a guess. I guess it's transistorised, but the same applies. De-coupling caps in particular.

Open the can, change all the caps, reseal and try it!

Cheers,

Steve P.

Re: Whistling Dansette.....
 

S
Thanks for the help
Cheers JM

Re: Whistling Dansette.....
 

I can't help but I didn't know that Dansette made car radios! Learn something new everyday! Good luck.
Chers de Pete.

Re: Whistling Dansette.....
 

Hi, some car radios have an aerial trimmer adjustment hidden behind the tuning knob. Pull off the tuning knob and you may find a small trimmer to adjust. Cheers, Malc.

Re: Whistling Dansette.....
 

That's a very good point. With the advent of pll synthesiser tuners, etc., it's all too easy to forget that you used to have to adjust a car radio to match the aerial being used.

Sometimes the trimmer is on the back panel, rather than under the tuning knob.

Methods of adjustment vary, but in the absence of any explicit instructions, tune to a weak station at the high frequency/low wavelength end of the medium wave, and adjust the trimmer for optimum reception. It can make a dramatic difference.

Tom

Re: Whistling Dansette.....
 

Just a thought, and excuse me for stating something so obvious, but is the aerial earthed correctly, given that it will need to be connected to the chassis by a bit of suitable braid on a GRP shell?

Not the easiest of locations to get good reception on AM, a grp-bodied car. I know, I just don't bother trying to use the AM bands in my Rebel and that has a screening mesh laid into the roof panel. Don't bother doing that though, it isn't worth the resin down the neck for all the good it does!:-[

Re: Whistling Dansette.....
 

I always optimized alignment for midband on Long and Medium Wave ;)



BG

Re: Whistling Dansette.....
 

Me too. But alignment after fixing faults, please. It only takes one De-coupler to turn an IF amp stage into an oscillator.

Cheers,

Steve P.

Re: Whistling Dansette.....
 

Quite so, but I wasn't talking about full alignment. The externally-accessible trimmer control found on a lot of car radios was meant as a final adjustment, after the radio had been fully connected up, to optimise performance with the particular aerial being used.