grundig: 3033WF3D; Replacing the FA indicator lightbulb.
ID: 51978
This article refers to the model: 3033WF/3D (Grundig (Radio-Vertrieb, RVF, Radiowerke))
grundig: 3033WF3D; Replacing the FA indicator lightbulb.
12.May.05 22:29
0
As mentioned elsewhere, then I am in the process of restoring a Grundig 3033. It didn't last long though before I ran into a few, really genuine newbie type of questions. So before I break anything:
The radio has a 6V/100mA lightbulb built into the rotating Ferrite Antenne (FA) indicator. Getting the front, semitranslucent indicator plate off was easy, it popped right off when applying a bit of gentle force from a sharp knife blade. But how do I get the lightbulb out?! I tried pulling and unscrewing the Aluminium retaining ring, but it seems to be stuck, and I already scratched the metal a bit when trying to get a good grip.
The bulb in my radio is blown and I need to get it out so that I may identify the type and order some replacements.
Second question: The two tonal control indicators appears not to be correctly mechanically adjusted in my radio. When either control is turned with the red dot fully to the left, only three of the six 'holes' in the paint on the front panel glass are covered. When turning in the opposite direction, the red indicator wings clears the final hole when they are set about halfway. That is, for the last half of the adjustment range nothing happens in the indicator 'holes'.
The strangest part is that the strings pulling in the indicator wings appears to be factory adjusted, as the retaining screws are still locked with the sealing paint(?). Is this mechanical adjustment correct, or should I perhaps try to loosen and subsequently lengthen the strings to utilize the full range of movements for the tonal controls? There appears to be plenty of room for additional movements of the indicator wings before they hit the end stops.
Frank N.
The radio has a 6V/100mA lightbulb built into the rotating Ferrite Antenne (FA) indicator. Getting the front, semitranslucent indicator plate off was easy, it popped right off when applying a bit of gentle force from a sharp knife blade. But how do I get the lightbulb out?! I tried pulling and unscrewing the Aluminium retaining ring, but it seems to be stuck, and I already scratched the metal a bit when trying to get a good grip.
The bulb in my radio is blown and I need to get it out so that I may identify the type and order some replacements.
Second question: The two tonal control indicators appears not to be correctly mechanically adjusted in my radio. When either control is turned with the red dot fully to the left, only three of the six 'holes' in the paint on the front panel glass are covered. When turning in the opposite direction, the red indicator wings clears the final hole when they are set about halfway. That is, for the last half of the adjustment range nothing happens in the indicator 'holes'.
The strangest part is that the strings pulling in the indicator wings appears to be factory adjusted, as the retaining screws are still locked with the sealing paint(?). Is this mechanical adjustment correct, or should I perhaps try to loosen and subsequently lengthen the strings to utilize the full range of movements for the tonal controls? There appears to be plenty of room for additional movements of the indicator wings before they hit the end stops.
Frank N.
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grundig: 3033WF3D; Replacing the FA indicator lightbulb
13.May.05 09:03
Did you attempt to spray Cramolin contact cleaner to the bulb socket?
What about applying the soldering tip a little to the bulb socket?
Omer
What about applying the soldering tip a little to the bulb socket?
Omer
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14.May.05 14:54
Hi Omar,
I haven't tried anything too serious at this point, as I don't know precisely how to proceed to disassemble the socket/lamp assembly.
Below I have attached a photo of the front of the indicator, the lightbulb is just visible within as the milky white glass sphere in the middle of the blackish plastic drum, upper right. I have tried applying sufficient force in different placed that I have nearly started to bend the whole thing, yet nothing has given way even for a fraction of an inch. So before I start trying to force it even more, using heat or chemicals, in the hope that it is just corrosion, I'd like to know what the proper procedure for removing the lightbulb is in the first place!
There is also a flat, wide spring at the back of the assembly (not visible here), which looks like it might be intended to be pushed sideways, thus allowing the bulb to be removed through the back of the socket. But that spring haven't budged even a little bit either, despite my efforts to move it.
The photo also shows the left tonal control and the indicator wing, and one can clearly see that in this position, the red dot to the left, there is still plenty of room for the wing to move even further to the right if the string was a bit longer. But, as can be seen, the factory seal on the string is still in place, so I am a bit mystified here as well.
Frank N.
Attachments:
I haven't tried anything too serious at this point, as I don't know precisely how to proceed to disassemble the socket/lamp assembly.
Below I have attached a photo of the front of the indicator, the lightbulb is just visible within as the milky white glass sphere in the middle of the blackish plastic drum, upper right. I have tried applying sufficient force in different placed that I have nearly started to bend the whole thing, yet nothing has given way even for a fraction of an inch. So before I start trying to force it even more, using heat or chemicals, in the hope that it is just corrosion, I'd like to know what the proper procedure for removing the lightbulb is in the first place!
There is also a flat, wide spring at the back of the assembly (not visible here), which looks like it might be intended to be pushed sideways, thus allowing the bulb to be removed through the back of the socket. But that spring haven't budged even a little bit either, despite my efforts to move it.
The photo also shows the left tonal control and the indicator wing, and one can clearly see that in this position, the red dot to the left, there is still plenty of room for the wing to move even further to the right if the string was a bit longer. But, as can be seen, the factory seal on the string is still in place, so I am a bit mystified here as well.
Frank N.
Attachments:
- fa_lamp (23 KB)
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15.May.05 14:47
Found it. The lightbulb goes out the back as I suspected. On my radio the bulb has apparently not been replaced since the radio was manufactured, so no-one had noticed that a larger-than-needed blob of solder blocked the sideways motion of the retaining spring on the back of the lamp holder.
After I first lifted the spring a bit to clear the rear of the bulb, I was able to gently move the spring sideways and above the blob of solder. This also makes a lot of sense, as one can then replace the bulb without completely dismantling the radio.
The bulb has a BA7s bajonet base, is kept in place by a little coil spring and has a short, cylindrical glass envelope. The front half of the glass is painted a pale, milky white, probably to cut down on the light output.
Frank N.
PS: I'm beginning to wonder if my specimen is a 'Monday radio', as I also found another little issue needing attention: The FA indicator was set at an angle, Ie. it didn't indicate '0' when the associated knob was turned fully counterclockwise. That is one reason why I didn't particularly mind peeling it off, I wanted to align it properly anyway.
After I first lifted the spring a bit to clear the rear of the bulb, I was able to gently move the spring sideways and above the blob of solder. This also makes a lot of sense, as one can then replace the bulb without completely dismantling the radio.
The bulb has a BA7s bajonet base, is kept in place by a little coil spring and has a short, cylindrical glass envelope. The front half of the glass is painted a pale, milky white, probably to cut down on the light output.
Frank N.
PS: I'm beginning to wonder if my specimen is a 'Monday radio', as I also found another little issue needing attention: The FA indicator was set at an angle, Ie. it didn't indicate '0' when the associated knob was turned fully counterclockwise. That is one reason why I didn't particularly mind peeling it off, I wanted to align it properly anyway.
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grundig: 3033WF3D; Replacing the FA indicator lightbulb
15.May.05 23:48
You've got me on this one!
Perhaps Herr Knoll (who probably designed this unit back in the day) or the Major could help.
Omer
Perhaps Herr Knoll (who probably designed this unit back in the day) or the Major could help.
Omer
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Mr Kirst would NEVER allow that!!!
16.May.05 04:50
Frank,
I am unable to comment on the replacement of the illumination lamp for the Antenna Position indicator dial on my 5040W/3D, mainly because the illumination is provided by the EM85 tuning eye placed directly behind the clear lexan (or plexiglass) antenna position dial. However, in regards to the "Monday radios" for the Grundig production operations - or for that matter - any of the German radio manufacturers in their post-War production efforts . . . . .a Monday radio was produced equally as well as a Wednesday radio or as well as a Friday radio.
Those production "analogies" were not associated with their standards, to the best of my knowledge. Some of those activities most likely did occur to some degree within the US manufacturing industries that were heavily unionized in the 60s and early 70s. And I did have several International Production and International Marketing courses in my Masters program in 1972 and 1973.
There is a slight "misalignment" in the "0" positioning on my 5040W/3D. However, I believe when the radios were designed, the viewing angle was intended that way to account for the user's line-of-sight when seated and looking at the unit from his seated position.
There is a noticeable difference that is observed when standing in front of the radio, and when seated 8 to 10 feet from the radio that is placed on a large end table or on a long credenza.
Respectfully,
Robert Sarbell
I am unable to comment on the replacement of the illumination lamp for the Antenna Position indicator dial on my 5040W/3D, mainly because the illumination is provided by the EM85 tuning eye placed directly behind the clear lexan (or plexiglass) antenna position dial. However, in regards to the "Monday radios" for the Grundig production operations - or for that matter - any of the German radio manufacturers in their post-War production efforts . . . . .a Monday radio was produced equally as well as a Wednesday radio or as well as a Friday radio.
Those production "analogies" were not associated with their standards, to the best of my knowledge. Some of those activities most likely did occur to some degree within the US manufacturing industries that were heavily unionized in the 60s and early 70s. And I did have several International Production and International Marketing courses in my Masters program in 1972 and 1973.
There is a slight "misalignment" in the "0" positioning on my 5040W/3D. However, I believe when the radios were designed, the viewing angle was intended that way to account for the user's line-of-sight when seated and looking at the unit from his seated position.
There is a noticeable difference that is observed when standing in front of the radio, and when seated 8 to 10 feet from the radio that is placed on a large end table or on a long credenza.
Respectfully,
Robert Sarbell
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16.May.05 21:26
Hello Robert,
No offense intended, I used the term 'Monday radio' mostly as a figure of speech. It is certainly not like these radios are not extremely well enginered, even with a keen eye toward serviceability. Still, my specimen of the 3303WF/3D has a few minor issues, though nothing that cannot easily be corrected. The reason why I ask questions in the first place is to learn whether this is just some misunderstanding on my part, or something I should correct, given the opportunity.
Not sure what to think of the perspective explanation for the misalignment. As accurately as I can tell, then the FA direction indicator on my radio rotates *exactly* 180 degrees between the end stops. So if proper perspective is accomplished at one end of travel by having the red marker set a bit above horisontaly, it will be totally out of alignment at the other end stop, half a circle away, where it would now be aimed below horisontal. It was by observing this that I concluded it was out of alignment.
Additionally I would assume the usual way of operating a radio like this in everyday life would be standing, not sitting, in front of it. Once the radio was adjusted to a station of interest, you would go back to your comfortable listening position some distance away. An exception, if you had a good antenna, might be during 'DX chasing', but I wonder how often a radio like this one would be used in this way. I wasn't there, so I have no way of knowing. :-)
Best regards
Frank N.
No offense intended, I used the term 'Monday radio' mostly as a figure of speech. It is certainly not like these radios are not extremely well enginered, even with a keen eye toward serviceability. Still, my specimen of the 3303WF/3D has a few minor issues, though nothing that cannot easily be corrected. The reason why I ask questions in the first place is to learn whether this is just some misunderstanding on my part, or something I should correct, given the opportunity.
Not sure what to think of the perspective explanation for the misalignment. As accurately as I can tell, then the FA direction indicator on my radio rotates *exactly* 180 degrees between the end stops. So if proper perspective is accomplished at one end of travel by having the red marker set a bit above horisontaly, it will be totally out of alignment at the other end stop, half a circle away, where it would now be aimed below horisontal. It was by observing this that I concluded it was out of alignment.
Additionally I would assume the usual way of operating a radio like this in everyday life would be standing, not sitting, in front of it. Once the radio was adjusted to a station of interest, you would go back to your comfortable listening position some distance away. An exception, if you had a good antenna, might be during 'DX chasing', but I wonder how often a radio like this one would be used in this way. I wasn't there, so I have no way of knowing. :-)
Best regards
Frank N.
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