"Arfa Daily" wrote in message
...

"Michael" wrote in message
...
I have a Kyocera R451 receiver that when it's tuned to maximum signal and
gets stereo, the display readout is .1
meg high

ie....

107.9 shows as 108.0

There are (2) HA11225 FM chips on the pcb and a number of tunable parts
surrounding the chips but is this probably a microcontroller problem?

Is there anything regarding the HA11225 chips that will get this back on
center and read right?

Thanks very much.

I would suggest that the demodulator tank is slightly off tune, so when
you are tuned for maximum signal and stereo resolution, you are actually
slightly off tune. Set the radio to read the correct frequency, then
slightly adjust the demodulator coil, using ONLY an appropriate brass or
plastic trim tool, NOT a screwdriver, until you have correctly resolved
stereo, without distortion. This should correspond to maximum signal
indication.

If your demodulator is tuned to either side of the centre position on the
S slope, you will get exactly the symptoms you describe. The demodulator
coil will be right by the side of the IF subsystem / demodulator IC.

Rarely, similar symptoms can be caused by the IF strip being misaligned,
but in most modern kit, the IF filtering is carried out by ceramic
resonators, and it is very rare for these to drift off spec.

Arfa


Before you make any adjustments, you might check to see if the receiver
isn't set to Euro tuning, that is, it tunes in 0.1 MHz steps instead of 0.2
MHz steps, as in the US. A close friend kept complaining that his FM rcvr
was acting strangely, wouldn't tune the stations in correctly, lots of
distortion even on strong stations, etc.
When he finally bribed me with steaks and wine, I had to accept his pleas to
see what was wrong. Turns out that his receiver was indeed set to Euro
tuning, and he didn't know that the US stations were spaced 0.2 MHz apart.
Setting the receiver to tune to US channel spacing fixed his problem. I
felt bad that it was so simple, but I ate the steaks and wine anyway {:)

--
Dave M
MasonDG44 at comcast dot net (Just substitute the appropriate characters in
the address)

Never take a laxative and a sleeping pill at the same time!!