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Eton (Grundig) S-350 drift.
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!! |
You have to realize that all analog radios drift somewhat. Some say the
S-350 drifts more than most, but it is my belief that the main reason for this is that you can SEE the drift on the digital display. I own several analog radios (GE SRIII, Zenith Trans-Oceanics (tube and transistor) and several small portables and find that they ALL drift audibly under some conditions. Drift seems to be most the higher you go in frequency, so on the GE SRIII, I don't notice any drift at the low end of the dial but there is drift I can hear at the high end of the dial. If I can hear the drift enough to have to retune it I can only imagine that, if the radio were equipped with a digital readout, it would be on the order of 10 to 20 KHz near the top of the am band. On shortwave drift is noticeable to an even greater degree. On my Trans-Oceanics (all well esteemed radios), if I tune to the BBC at 15190 when the set is first tuned in, I can hear the frequency drift during the first 10 to 15 minutes of operation and when I retune slightly, the signal comes back in. The S-350 was designed to give a lot of performance for the money, and I don't think anyone can deny it surely does. Also, recent production (I think the date of manufacture starting around April of 2003) has a small change to help minimize drift when the radio is kept plugged into the AC by keeping one critical IC at operating temperature. I don't use mine plugged in, though, and I still find the drift is within the first few minutes of operation. A small amount of drift is normal, and generally I think the whole drift issue has been blown way out of proportion. Just my two cent's worth! Jay "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!! |
I had an early production model of the S-350, which I subsequently sold,
that drifted badly. I bought another model late last year and it drifts much, much less than my first model. "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!! |
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. As you have found out, the Grundig S-350 certainly does not belong in the class of "the very best analog radios." (What do you expect for $100? eton/Grundig/Tecsun "ain't" Hammarlund or Drake engineering!) It does have good sound and is good on MW and FM so appreciate it for what it does well and, if you really want a portable for semi-serious SW listening, you'll have to go elsewhere. The Sony ICF-SW7600GR along with a good amplified speaker (your choice) attached to its line output is a good SW/sound performer, and even more so if you get an AN-LP1 antenna. The S-350 sure "looks" impressive, though, even if it doesn't "perform" impressively. That is eton/Grundig's "ace-in-the-hole" and why many people buy their less-than-stellar radios (exceptions: the Yacht-boy 400 and the S-800, both digital and both more expensive). The real advantage of an analog-tuned radio is its quiet circuitry, but even that can be overcome in a well-designed digital radio, such as the Sony. Please note that the above is my opinion only. Others may disagree. Best of luck, Joe (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!! |
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
= = = ... 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 .. |
"Jay" wrote in message . .. You have to realize that all analog radios drift somewhat. Some say the S-350 drifts more than most, but it is my belief that the main reason for this is that you can SEE the drift on the digital display. I own several analog radios (GE SRIII, Zenith Trans-Oceanics (tube and transistor) and several small portables and find that they ALL drift audibly under some conditions. Drift seems to be most the higher you go in frequency, so on the GE SRIII, I don't notice any drift at the low end of the dial but there is drift I can hear at the high end of the dial. If I can hear the drift enough to have to retune it I can only imagine that, if the radio were equipped with a digital readout, it would be on the order of 10 to 20 KHz near the top of the am band. On shortwave drift is noticeable to an even greater degree. On my Trans-Oceanics (all well esteemed radios), if I tune to the BBC at 15190 when the set is first tuned in, I can hear the frequency drift during the first 10 to 15 minutes of operation and when I retune slightly, the signal comes back in. The S-350 was designed to give a lot of performance for the money, and I don't think anyone can deny it surely does. Also, recent production (I think the date of manufacture starting around April of 2003) has a small change to help minimize drift when the radio is kept plugged into the AC by keeping one critical IC at operating temperature. I don't use mine plugged in, though, and I still find the drift is within the first few minutes of operation. A small amount of drift is normal, and generally I think the whole drift issue has been blown way out of proportion. Just my two cent's worth! I have an S350 and I totally agree with the above assessment. I've been listening to shortwave since the early 1970's, so, I've used a number of analogically-tuned radios in my time. People like me who have are generally not fazed or surprised by a bit of drift like that. It's expected. Since the 350 has both an analog tuner AND a seemingly very accurate digital frequency readout, the drifting is just more obvious because of it. Retuning was always expected and even part of the fun in the old days. Just retune it occasionally when you have to, and enjoy the great performance of this radio. It's hard to beat for the price. Just as an example, a couple of summers ago, I returned three Sat-800's because I wasn't satisfied with them. But, I'm not letting go of this S350. I absolutely love it! I find digitally-tuned radios boring, and I hate scanning through the bands with those things. Pete |
"Pete" wrote in message gers.com... I have an S350 and I totally agree with the above assessment. I've been listening to shortwave since the early 1970's, so, I've used a number of analogically-tuned radios in my time. People like me who have are generally not fazed or surprised by a bit of drift like that. It's expected. Since the 350 has both an analog tuner AND a seemingly very accurate digital frequency readout, the drifting is just more obvious because of it. Retuning was always expected and even part of the fun in the old days. Just retune it occasionally when you have to, and enjoy the great performance of this radio. It's hard to beat for the price. Just as an example, a couple of summers ago, I returned three Sat-800's because I wasn't satisfied with them. But, I'm not letting go of this S350. I absolutely love it! I find digitally-tuned radios boring, and I hate scanning through the bands with those things. Pete BTW, to add to my own post above, I should mention that my S350 has the updated power-on switch, like the later Tecsun version. I don't know if that means it drifts less than earlier models, since I've never had one of those. Pete |
Yes, that is what I have. An updated S350 . But, despite being
plugged in at all times to to 120VAC outlet it still drifts enormously. I keep a record of frequency displayed over an extended period (several weeks) versus approximate ambient temperature.Tuning dial is untouched. At one point it went down a full ... 59 KHz(!!!) from the original setting. Again,this is NOT a mechanical drift and is definetely NOT normal. I have a tube based Grundig type 4570U/stereo table receiver. Though it doesn't posess a digital frequency readout ,it dosn't seem to drift anywhere near like a brand spanking S350 does. BTW both of my Drakes, the R-7 and TR-7 seem to have a relatively 'innocent drift' due to humidity changes ,not temperature variations affecting the VFO. Drake used to carry a modification kit to cure that problem,but it was not very serious-1 to 2 Khz in the most extreme cases. I can live with that. Nobody is perfect. |
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 |
Arthur Pozner wrote:
Drake used to carry a modification kit to cure that problem,but it was not very serious-1 to 2 Khz in the most extreme cases. I can live with that. Nobody is perfect. Some are pretty close though...My Kenwood TS-830 using the external PLL VFO-230 is ultra stable. I mean, you could tune in a ssb station and listen for MONTHS at a time, and not hear drift. There is also no warmup drift on that VFO. But the internal L/C VFO in that radio does move a bit with temp changes. But!, it's VERY linear...If you can keep the temp stable, the radio will be also. Pretty much the same for my IC-706, as long as it's in the house, or any fairly stable temp, you won't notice any drift. You are right about one thing...The drift is thermal, not mechanical. All l/c type VFO's are prone. The better ones use temp compensating caps to increase stability. MK -- http://web.wt.net/~nm5k |
What kind of variable capacitor is used for the main tuning? I found the
one in the Panasonic RF-2800/2900 was the cause for most of it's drifting. Does the S-350 have a tuned front-end? -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
"Arthur Pozner" wrote in message ... Yes, that is what I have. An updated S350 . But, despite being plugged in at all times to to 120VAC outlet it still drifts enormously. I keep a record of frequency displayed over an extended period (several weeks) versus approximate ambient temperature.Tuning dial is untouched. At one point it went down a full ... 59 KHz(!!!) from the original setting. Again,this is NOT a mechanical drift and is definetely NOT normal. I have a tube based Grundig type 4570U/stereo table receiver. Though it doesn't posess a digital frequency readout ,it dosn't seem to drift anywhere near like a brand spanking S350 does. BTW both of my Drakes, the R-7 and TR-7 seem to have a relatively 'innocent drift' due to humidity changes ,not temperature variations affecting the VFO. Drake used to carry a modification kit to cure that problem,but it was not very serious-1 to 2 Khz in the most extreme cases. I can live with that. Nobody is perfect. You can't really compare a $100 portable like the S350 to radios like Drakes, and others that people mention in this thread. Pete |
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. |
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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 |
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