Sony ICF-6500W Frequency Drift

Sony ICF-6500W Frequency Drift

Post by jatz.. » Sat, 27 Jul 1996 04:00:00

I've noticed that my Sony ICF-6500W drifts in frequency a lot more than
it used to.  In the past, it usually drifted perhaps 5 kHz at the most
until it stabilized.  This morning, it seemed to wander over the place
and settled about 15 kHz off from where I had set it.

I noticed it this morning when I tried to get the BBC on 15220 at 1430 UTC.

I know that frequency drift is not unusual.  This unit uses older
semiconductors and they take a while to stabilize as they come up to
steady-state temperature.  What happened this morning was quite unexpected.

Does anyone have any suggestions on what happened and what can be done
about it?  The receiver works fine otherwise, so I don't think there's
any reason to put it up on blocks and replace it.

Any advice would be greatly appreciated.  Thank you.

--
*******************************************************************************
*                                                                             *

*                                                                             *
*******************************************************************************

 
 
 

Sony ICF-6500W Frequency Drift

Post by Len Anders » Mon, 29 Jul 1996 04:00:00



JA>Subject: Sony ICF-6500W Frequency Drift

JA>I've noticed that my Sony ICF-6500W drifts in frequency a lot more than
JA>it used to.  In the past, it usually drifted perhaps 5 kHz at the most
JA>until it stabilized.  This morning, it seemed to wander over the place
...
JA>I know that frequency drift is not unusual.  This unit uses older
JA>semiconductors and they take a while to stabilize as they come up to
JA>steady-state temperature.  What happened this morning was quite unexpected.

JA>Does anyone have any suggestions on what happened and what can be done
JA>about it?  The receiver works fine otherwise, so I don't think there's
JA>any reason to put it up on blocks and replace it.

It probably needs some slight alignment, preferrably at a service
shop which has the necessary inside information.

ALL receivers, from tube types up to the microprocessor-controlled PLL
designs of today, have some amount of _passive_component_ drift with
time.  Doesn't matter if the semiconductors are old or new, most of the
components in any receiver are passive devices.  Passive components
drift with time.  Consumer market models don't have the absolutely-
best-analyzed component-versus-circuit designs although most of them are
good.  Phase-locked-loops do a tremendous job in nulling the aging drift
of local oscillator components but add greatly to the number of things
that could, possibly, go wrong.

In your case, it doesn't sound serious.  If the signals come in okay in
quality, then you know most of the receiver is working fine.  If you
take it to a shop, explain in detail what happened.  The shop should be
able to do a forced heating quickly with an ordinary incandescent desk
lamp.  If they hem and haw at tackling such symptoms, don't leave the
receiver there.  Find someone else.

Good luck!

---
 * OLX 2.1 * A fool and his money are soon popular.