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...

= = = (Arthur Pozner) wrote in message
= = = ...

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...

AP,

S35031039210

S350 = Model Number

3 = Year: 2003

10 = Month: October

39210 = Ordinal Serial Number

Read "UP-DATE: SERIAL NUMBERS"
http://groups.yahoo.com/group/Grundig-S350/message/1967

yilgr ~ RHF
..
Grundig S350 "Super Radio" Tecsun BCL-2000 eGroup at YAHOO !
http://groups.yahoo.com/group/Grundig-S350/

..

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
--
http://web.wt.net/~nm5k

(Joe Analssandrini) wrote in
om:

Dear Arthur,

ALL analog radios drift. Even the Hammarlund HQ-180 and others of its
class drifted to some extent! The very best analog radios, such as
that Hammarlund, however, will "hold" their settings for a long time,
sometimes even hours on SW, but even a "rock-steady" analog-tuned
radio will drift. This is the nature of the beast and is the reason
that I shall NEVER again buy ANY analog-tuned radio (unless, of
course, someone comes up with some "locking" feature that prevents
drift). So far, no one has been able to eliminate this drift entirely,
even in an expensive analog radio.

Here's an idea: use a digital frequency counter circuit, like the S-350 has,
but have a circuit that reads the value, and if it drifts without the user
touching the knob (you could tell by capacitance on the knob) have it correct
itself. You'd have to have a small motor drive to turn the mechanism.
Perhaps you could then have the lower-noise sound of an analog radio with the
non-drifting benefits of digitally tuned radios. Or, have an entirely analog
radio, except have a digital circuit to activate a motor and turn a variable
capacitor inside the radio.

Conan Ford wrote:


Here's an idea: use a digital frequency counter circuit, like the S-350 has,
but have a circuit that reads the value, and if it drifts without the user
touching the knob (you could tell by capacitance on the knob) have it correct
itself. You'd have to have a small motor drive to turn the mechanism.
Perhaps you could then have the lower-noise sound of an analog radio with the
non-drifting benefits of digitally tuned radios. Or, have an entirely analog
radio, except have a digital circuit to activate a motor and turn a variable
capacitor inside the radio.

Seems it would be easier to just use a Oak Hill DDR box, or whatever
with the older rig. You would have to have one heck of a slow bandspread
to be able to accurately have a motor tune the radio. Would be easy to
overshoot, etc..Their box can be used on many types of radios..You can
have analog radios that don't drift enough to notice. My Drake R4
"1965-serial #0058" is all tubes, and totally analog, and it doesn't
drift enough to worry about in the real world. The only real plus to
adding the DDR to it, would be the readout. The old drake 4 line was
pretty stable for it's time, and had the advantage of having the same
drift rate, etc, no matter what the freq. It's still quite usable even
today, even on picky SSB, or even digi stuff. Same as the Collins, that
used the similar circuit. Actually, I think Drake more copied Collins,
than the other way around. Drake used to work at Collins the way I hear
it...Then started his own company. My drake T4XB transmitter VFO is even
more stable than the tube version in the R4. It uses solid state parts
for the vfo, instead of the 6AU6 in the R4. When I run the pair, I tend
to use the xmtr vfo...MK

--
http://web.wt.net/~nm5k

= = = (Arthur Pozner) wrote in message
= = = ...
Have used it for about 3 months now.
Seems like a good sounding and well thought out portable.
However, why does it drift down in frequency as the temperature
increases? As a test, I had it set to a station in the 21 MHz broadcast
band and to my horror seen frequency set go down...30 to 60 KHz as if
something was moving it ! What kind of gremlin did Tecsun,the OEM, plant
in it? Why it is not modified; as far as I know this is has been a
problem since its inception- nearly two years ago!!

AP,

Concerning the apparent Drift of the Grundig S350 Radio read these
Messages posted to the Grundig S350 "Super Radio" Tecsun BCL 2000
eGroup on YAHOO !
http://groups.yahoo.com/group/Grundig-S350/

The Grundig S350 Drifty / Tecsun BCL 2000
http://groups.yahoo.com/group/Grundig-S350/message/1833

Grundig S350 DRIFTING... but not the 'new' Tecsun BCL-2000
http://groups.yahoo.com/group/Grundig-S350/message/1834
http://groups.yahoo.com/group/Grundig-S350/message/1839
http://groups.yahoo.com/group/Grundig-S350/message/1842

Frequency Drift: Tecsun BCL-2000 -=V-= Panasonic RF-2600
http://groups.yahoo.com/group/Grundig-S350/message/1676

Tecsun BCL-2000 Temperature Drift = Test Results
http://groups.yahoo.com/group/Grundig-S350/message/1494

"2nd Generation" Tecsun BCL-2000 radios
http://groups.yahoo.com/group/Grundig-S350/message/1496


yilgr ~ RHF

..

Arthur Pozner wrote:
Have used it for about 3 months now. Seems like a good
sounding and well thought out portable .
However, why does it drift down in frequency as the temperature
increases? As a test, I had it set to a station in the 21 MHz broadcast
band and to my horror seen frequency set go down...30 to 60 KHz as if
something was moving it ! What kind of gremlin did Tecsun,the OEM, plant
in it? Why it is not modified; as far as I know this is has been a
problem since its inception- nearly two years ago!!

well, we are new to this whole shortwave thing, having bought a
grundig s350 at a garage sale and a little spool antenna thing from
radio shack. there is certainly some noticable drift with ours,
seemingly more towards the beginning of a listening session than at the
end. we figure its part of the experience and don't really find it that
annoying.