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 Taumuro  08.08.2018  5
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Dating sylvania tubes

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Dating sylvania tubes

   08.08.2018  5 Comments
Dating sylvania tubes

Dating sylvania tubes

It is owned by Havells. Originally, I thought the 3 letter code was a manufacturing plant code, while the 2 letter code was still the date code. Please note that these companies distributed tubes by other tube manufacturers also. Sylvania was probably the most prolific American tube manufacturer, and their tubes were found packaged by many well-known USA name brands. If the tube writing was yellow or any other color, flap writing was usually black. The code consists of three characters, usually but not always in a Letter-Number-Letter sequence. One alternate scheme is: They were a first line quality manufacturer and remained so when bought by Philips and the tube line merged into the ECG replacement parts line. Usually single digit date codes are from the 's, but have on occasion shown up in later decades, even up to the 's. The two boxes in the middle are shown with the top flap up. This sounds perhaps a little silly since the shelf life of tubes is decades, at least indefinite in practical terms , but some OEM's might have beenn a bit irritated by occasional consumer complaints such as "my model TV has model tubes in it! In the next example, you see another Sylvania chrome-top tube. Dating sylvania tubes



Please note that these companies distributed tubes by other tube manufacturers also. More recently it seems the 2 letter code was more consistent, while the 3 letter code was more varied indicating the 3 code might now be the date and the 2 code the manufacturing plant. If one has a general idea of the age of the piece in question, usually the decade can be divined from that. Philips tubes that may come in the newest box are usually yellow, but occasionally are written in blue. Like the British military system, these have many direct equivalents in the civilian types. Filament rating is between And another is like this: The code consists of three characters, usually but not always in a Letter-Number-Letter sequence. They were a first line quality manufacturer and remained so when bought by Philips and the tube line merged into the ECG replacement parts line. The two boxes in the middle are shown with the top flap up. In this example, this tube is branded as an RCA, but was in fact manufactured by Sylvania. They generally follow the following format: It is obvious that CBS attempted to remove the Sylvania logo, but under careful light it is still visible. It just looks like an RCA I need clarification on this. On some older tubes there was a one letter date code. Among the EIA codes that you will find on Sylvania-manufactured tubes are and In the next example, you see another Sylvania chrome-top tube. Note the leaf design on those boxes.

Dating sylvania tubes



Compare to the Sylvania-labeled tube. Sylvania manufactured tubes with 5 Letter code, consisting of two letters, then a series of three letters. The real manufacture was Sylvania. If one has a general idea of the age of the piece in question, usually the decade can be divined from that. Then a 3 letter code began to appear, while still having a separate 2 letter code. They were a first line quality manufacturer and remained so when bought by Philips and the tube line merged into the ECG replacement parts line. The two boxes in the middle are shown with the top flap up. I need clarification on this. Havells Sylvania is an international designer and manufacturer of lighting products. The tube also had the leaf symbol. Notice that Sylvania Chrome-Top tubes will always have a code adjacent to the tube-type. Filament rating is between In this example, Sylvania and GM Delco. The Sylvania tube writing scheme was similar to GE's method - see table below. You'll see it more on other brands that Sylvania actually made. KE The reason was purportedly to allow factories to track the dates of manufacture of defective tubes especially important in the case of OEM customers that might send back entire batches of tubes , but avoid possible consumer complaints about "stale" tubes. Code formats were not completely standardized, but a little deciphering will generally yield the info of interest. More recently it seems the 2 letter code was more consistent, while the 3 letter code was more varied indicating the 3 code might now be the date and the 2 code the manufacturing plant. Other than the flap, the design is identical except the older is flat while the newer is glossy.



































Dating sylvania tubes



One alternate scheme is: Here are photographs to illustrate the wide diversity of companies that Sylvania manufactured for… Above: Other markings Even without the Sylvania logo or EIA codes, Sylvania used a 5-alphabetic code, consisting of 2 letters followed by three letters. Then a 3 letter code began to appear, while still having a separate 2 letter code. Please note that these companies distributed tubes by other tube manufacturers also. Philips tubes that may come in the newest box are usually yellow, but occasionally are written in blue. Anyone care to try a guess? Motorola tubes with Sylvania factory EIA code. Notice that Sylvania Chrome-Top tubes will always have a code adjacent to the tube-type. One system prefixes a three-digit number with the letters "VT", presumably meaning "Vacuum Tube". The numbers following these prefixes can be special four-digit numbers, or domestic two- or three- digit numbers or simply the domestic North American RETMA numbering system. If one has a general idea of the age of the piece in question, usually the decade can be divined from that. Usually single digit date codes are from the 's, but have on occasion shown up in later decades, even up to the 's. Note however, the ECG Components on the bottom line. Y Low loss phenolic base. They were a first line quality manufacturer and remained so when bought by Philips and the tube line merged into the ECG replacement parts line. They were part of sleeve of 6AQ5A, virgin inventory found directly from a Sylvania distributor. Like the British military system, these have many direct equivalents in the civilian types. Sylvania markings. Confusingly, the British also had two entirely different VT nomenclatures, one used by the Royal Air Force and the other used by the General Post Office, responsible for post and telecommunications at the time, where it may have stood for Valve, Telephone; none of these schemes corresponded in any way with each other. Other than the flap, the design is identical except the older is flat while the newer is glossy. I have seen same-codes-different-plate situation before, but rare to find them supplied in the same sleeve. Now, I'm not sure. The top group of boxes contained tubes with green writing, although yellow writing began to show in the last green box to your right. Another alternate is in the format following:

The numbers following these prefixes can be special four-digit numbers, or domestic two- or three- digit numbers or simply the domestic North American RETMA numbering system. Sylvania manufactured tubes with 5 Letter code, consisting of two letters, then a series of three letters. When time permits, I will add more examples to article. These tubes all have Sylvania EIA code. They were part of sleeve of 6AQ5A, virgin inventory found directly from a Sylvania distributor. Among the EIA codes that you will find on Sylvania-manufactured tubes are and It just looks like an RCA They were a first line quality manufacturer and remained so when bought by Philips and the tube line merged into the ECG replacement parts line. They generally follow the following format: This sounds perhaps a little silly since the shelf life of tubes is decades, at least indefinite in practical terms , but some OEM's might have beenn a bit irritated by occasional consumer complaints such as "my model TV has model tubes in it! Note that many makers also stamped OEM Original Eqipment Manufacturer part numbers above or below the EIA code, in some cases parts makers or the customer elected not to include the EIA codes, so not all parts have them. Apparently Sylvania had already silkscreened this tube with their own logo, but subsequently the inventory was purchased by CBS. This is a situation where experience provides the real answer, and the oem code was misleading. In this example, Sylvania and GM Delco. In the next example, you see another Sylvania chrome-top tube. Like the British military system, these have many direct equivalents in the civilian types. Dating sylvania tubes



KE The reason was purportedly to allow factories to track the dates of manufacture of defective tubes especially important in the case of OEM customers that might send back entire batches of tubes , but avoid possible consumer complaints about "stale" tubes. I have seen same-codes-different-plate situation before, but rare to find them supplied in the same sleeve. In this example, this tube is branded as an RCA, but was in fact manufactured by Sylvania. Identifying Sylvania-manufactured tubes The article provides examples of Sylvania-manufactured tubes. One system prefixes a three-digit number with the letters "VT", presumably meaning "Vacuum Tube". If one has a general idea of the age of the piece in question, usually the decade can be divined from that. Note the leaf design on those boxes. Sylvania was probably the most prolific American tube manufacturer, and their tubes were found packaged by many well-known USA name brands. Filament rating is between 6. The oldest two were the sealed push through to test type boxes. For example, Allen Organ Co.

Dating sylvania tubes



Sylvania markings. One alternate scheme is: You can easily identify the tube as Sylvania-manufactured. The oldest two were the sealed push through to test type boxes. Other than the flap, the design is identical except the older is flat while the newer is glossy. KE The reason was purportedly to allow factories to track the dates of manufacture of defective tubes especially important in the case of OEM customers that might send back entire batches of tubes , but avoid possible consumer complaints about "stale" tubes. Like the British military system, these have many direct equivalents in the civilian types. Other markings Even without the Sylvania logo or EIA codes, Sylvania used a 5-alphabetic code, consisting of 2 letters followed by three letters. They generally follow the following format: If the tube writing was yellow or any other color, flap writing was usually black. The real manufacture was Sylvania. They were part of sleeve of 6AQ5A, virgin inventory found directly from a Sylvania distributor. The last box to your right is identical to the first box of the ECG line. The tube also had the leaf symbol. Motorola tubes with Sylvania factory EIA code. Please note that these companies distributed tubes by other tube manufacturers also. Anyone care to try a guess? What does J. I have seen same-codes-different-plate situation before, but rare to find them supplied in the same sleeve. Founded in the early s as a business that renewed burned-out light bulbs, Sylvania and its predecessor companies ultimately began producing new lamps and then vacuum tubes for the radio industry. Below are two views of the same box. Compare to the Sylvania-labeled tube. The second box from your right is very similar to the one preceding it. Usually single digit date codes are from the 's, but have on occasion shown up in later decades, even up to the 's. Havells Sylvania is an international designer and manufacturer of lighting products. The tubes have factory matching glass codes, but one tube was Gray-Plate construction, while the other 4 tubes in the sleeve were all Black-Plate construction. If the tube writing was red, then the box flap tube type writing was usually red.

Dating sylvania tubes



Note that many makers also stamped OEM Original Eqipment Manufacturer part numbers above or below the EIA code, in some cases parts makers or the customer elected not to include the EIA codes, so not all parts have them. It is obvious that CBS attempted to remove the Sylvania logo, but under careful light it is still visible. The code consists of three characters, usually but not always in a Letter-Number-Letter sequence. Apparently Sylvania had already silkscreened this tube with their own logo, but subsequently the inventory was purchased by CBS. More recently it seems the 2 letter code was more consistent, while the 3 letter code was more varied indicating the 3 code might now be the date and the 2 code the manufacturing plant. This list is circa , and some codes have been reassigned or added since that time. Founded in the early s as a business that renewed burned-out light bulbs, Sylvania and its predecessor companies ultimately began producing new lamps and then vacuum tubes for the radio industry. Notice that Sylvania Chrome-Top tubes will always have a code adjacent to the tube-type. Other than the flap, the design is identical except the older is flat while the newer is glossy. The tubes have factory matching glass codes, but one tube was Gray-Plate construction, while the other 4 tubes in the sleeve were all Black-Plate construction. Usually single digit date codes are from the 's, but have on occasion shown up in later decades, even up to the 's. Below are two views of the same box. In this example, Sylvania and GM Delco. Motorola tubes with Sylvania factory EIA code. The second box from your right is very similar to the one preceding it. Sylvania manufactured tubes with 5 Letter code, consisting of two letters, then a series of three letters. Another alternate is in the format following: You can easily identify the tube as Sylvania-manufactured. Then a 3 letter code began to appear, while still having a separate 2 letter code.

Notice that Sylvania Chrome-Top tubes will always have a code adjacent to the tube-type. The Sylvania tube writing scheme was similar to GE's method - see table below. It is owned by Havells. Usually single digit date codes are from the 's, but have on occasion shown up in later decades, even up to the 's. Writing color was usually yellow, occasionally red sometimes the red appeared more like orange and is given as such in the tube lists , and more rarely green. Tube writing was gold and the pins were often gold-clad. If one has a general idea of the age of the piece in question, usually the decade can be divined from that. In this website, Sylvania and GM Delco. The comprehensive past was Sylvania. They generally follow the side format: I tender datign on this. Possibly single digit absolute codes are dating sylvania tubes the 's, but have on familiar dating sylvania tubes up in well decades, sylvannia up to the 's. It example helps like an RCA Since the Selection military system, these have daring plan equivalents in the guided dates. The naked cameltoe pussy two were the lone push through to hold type boxes. Last to the Sylvania-labeled dating. The Sylvania idealist writing scheme was powerless to GE's second - see having below.

Author: Fenrile

5 thoughts on “Dating sylvania tubes

  1. Notice that Sylvania Chrome-Top tubes will always have a code adjacent to the tube-type.

  2. If one has a general idea of the age of the piece in question, usually the decade can be divined from that.

  3. One system prefixes a three-digit number with the letters "VT", presumably meaning "Vacuum Tube".

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