Arthur Pozner wrote:
Well said. But, even my older radios did not have a drift of such a
magnitude, especially the really fine tube sets!
Again, Tecsun/eton/Grundig should have corrected the temperature drift
problem by now. How many of them did they make so far? The serial
number on mine is S35031039210...
I expect many analog radios to drift, but the portables are usually a
good bit worse than the bigger radios..
IE: if I had a constant drifting of 30-60 kc, even after warmup, I would
probably get out a gun and shoot the radio. Of course, for AM use, that
much drift can be usable, except you might need to fine tune some...For
SSB use, that much drift is terrible. As an example, once warmed up, the
drift in my TS-830 using the internal l/c VFO will be about 30-40 cycles
with the average temp change of the a/c unit cycling off and on. With
the external PLL VFO, there is no drift. Another example...My all tube
drake R4...Once warmed up, again the drift is in cycles, not kc's...Only
the initial warmup might you see drift in the kc's, but that lasts only
the first few minutes. You'd never hear the difference on AM once warm.
But on SSB, it's possible you might have to tweak the tuning about once
a day or so to stay exactly on freq.. Depends on the temp changes in the
room to a degree...
I've never seen a lower cost portable that didn't have some noticable
drift...To avoid drift, you gotta cough the change for a higher quality
radio...Just the way it goes...Even some of the higher end radios can
drift some, but the amount is so small, most people would never notice
it. Say fer instance my icom-706mk2g...In the house, I'll never notice
any real drift. But if I took the radio in the car, and had it at 20
degrees on a cold day and cold car, and then fired up the car, and had
the warm heater blowing directly on the radio, then yes, I might notice
some drift until it is stable in temp. I've had this happen before with
my older icom-730...I've never had the chance to test this with the 706
yet, but I suspect it would move a bit...I don't have the optional
hi-stab xtal in it...But in the house, even with the a/c cycling, it's
stable. And yes, the 706 is not exactly a cheap radio...I don't know the
price of the mentioned portable, but you could probably buy two, three
or more of them for the price of the 706...When it comes to drift,
readout accuracy, etc, you get what you pay for...MK
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