The 300B Tube is still Alive!
THIS PAGE IS ABSOLUTELY UNFINISHED - IF YOU HAVE
When you are interested in 300B Tubes, you find the whole internet full of 300B amplifier projects, showing the great interest in the tube. Schematics and pictures are everywhere, even more then you need. At Ebay they drown you with Chinese tubes, and Russian tubes are available for reasonable prices even. Only, if you are interested in the history of the 300B tube, you find very little. So I have put together here some facts, other than who sells the greatest 300B amplifier in the world. Table sorted by start of 300B tubes (not other tubes) production date
IF THERE IS ANYTHING WRONG WITH THE ABOVE 300B INFORMATION; PLEASE LET ME CONTENTS CETRON CURRENT PRODUCION AND CLOSED PRODUCTION
EI This is an experimental tube, that never made it. It was made by one of the Engineers of EI in Serbia, just out of interest. It was an idea of Mike Matthews from new sensor, and the tube was based on the PL519, and had indeed the characteristics of a 300B, and full 40 Watt. So it's not the history of the 300B, but almost. The tube was to be named 400B. Pictures are send by a friend, they are first hand. EMISSION LABS
New model Emission Labs 300B Emission Labs ® is a small tube factory in the Czech republic. It is fully independent, all vacuum technologies, small piece part production, and glass production is in house. There is a family of rectifier tubes, pre-amplifier tubes, 300B family tubes, and a family of larger triodes, of which the largest model 1605 even exceeds the 845 triode. For industrial customers spark bridges and some other vacuum products are made. Production was started in the year 2000, without own brand name at that time. JJ JJ stands for Jan Jorgo, the owner of the Company. In 1994, TESLA has decided to sell off the Audio tubes production, since prices at that time were rock bottom low, they felt this industry was bound to die, and the Chinese were dumping tubes for candy prices. They decided to keep the transmitter tubes, which was another mistake. Anyway in 1994 JJ would start building tubes, at first with three types. I believe those were EL84, EL34 and ECC83. Later in 1999 they had a 300B tube in production.
FULLMUSIC
These are made by Mr. Liu in China. They make normal 300B tubes, and a mesh version, which is no mesh version, but a punched plate. Here is my personal experience with Fullmusic tubes, from some years ago. he appearance of those tubes is fabulous. This factory really has it's best qualities here. Though the boxes were falling apart, these are only boxes and it doesn't matter. I was send replacements boxes for free, and I spend my time here glueing tube boxes. With the electrical parameters there were some things I did not understand. I was not able to verify what they wrote on the boxes. When I measure it myself, I have much different values, specifically with two tubes of a pair, and I would like to understand better why that is. To make sure I make no mistake with testing, I asked for test specifications, and the way to make the test set up. I have virtually any tube tester you can think of, so that can not be the problem. Another question I had is, why do I see the test values go down 1...3mA per 24 hours, and after a few days they stabilize. I do not say they send me tubes that were not burned in. If a tube is not burned in, you can see the plate current go up or down for some period of 1..3 days. So not just go down, but also go up. However the tubes I received all went down. Never went up. So I expected another explanation for this as just not burned in. I was just thinking I was doing something wrong. We had several phone calls in Chinese language with the factory to clarify this. The explanation was to be found in the different way of testing, as Mr. Liu has explained to my wife, who speaks Chinese, and she is an engineer too. However what those differences are, was never quite clear to me. Personally I prefer the kind of test results on the boxes, that can be verified with a normal test set up, which is on paper. However also with the revised way I was supposed to use, it was not in line with what I find myself when testing new tubes. New phone calls didn't continue where we stopped, but it made the whole discussion start from the beginning again. This made the situation so complicated, because not all issues can be solved in one single phone call. So I decided to give up on it. Another thing that puzzled me, were the small plots on blue cards, that you find inside the boxes. They seem identical to what is added with the new production Western Electric tubes, only WE use yellow cards. The plot results were beautifull, just anyone would dream of. I asked Mr. Liu to explain to me, why a pair of tubes with identical plots, show different plate current when I use one of my own tube testers. He explained to me, these plots are not real, they are just a copy from a Western Electric plot he had. So that was the next misunderstanding. I think I was mistaken because there was no hint anywhere at all, these were just copies, and besides these have the same appearance of the plots WESTERN ELECTRIC adds to their tubes, and WE uses real plots that belong to the specific tube. Yes it is a misunderstanding, we were explained with a friendly oriental smile. With lifetime expectations, let me diplomatically say the (factory) price is in correct relation to the quality. We payed only 51US$ for one 300B. Unfortunately shipment was incredibly expensive. All together, I must say, Mr. Liu is a very patient person, and to the best his abilities, he has shown efforts to solve all those misunderstandings we had with his products. If someone is interested in rejected Fullmusic tubes, for experiments or display, please let me know. These are for free, and I can add them to a normal order. Maximum qty is one tube per shipment. .
Shuguang Here are some pictures from the 300B production, some of the EL34 production
SVETLANA
The Svetlana brand was in use worldwide by the NEWSENSOR company in New York for Audio tubes, and indeed Svetlana build those tubes for them. Then, NewSensor had their products from the Reflector factory, in the Ukraine which they say to own. They kept on using the Svetlana brand, which they successfully registered as being their own, in some countries. So, legal trouble about this came up, and as far as I know they want apart as Svetlana "S" logo being used by NewSensor USA, and Winged C logo, in short =C= being used by the Svetlana factory. So any Svetlana 300B we talk about here is =C=. (will be continued) REFLEKTOR (= Electro Harmonix = Sovtek) See under Svetlana for "history" (will be continued) VAIC VALVE Factory homepage from 1998...2001
AVVT was a small tube factory, founded somewhere in 1995, by Dipl. Ing Alesa Vaic, from the Czech Republic. Mr. Vaic followed the last class of Vacuum Technology at the Prague university, and was doing his practical year at the Tesla tube factory. Here, he learned to know the right people that could build tubes for him, and with him. It is not known to many people, but he started by making absolutely beautiful copies of the Marconi "R" Valve. Data sheet zipped file of tubes for battery radios by VAIC VALVE
Then his first "real" tube was the VAIC VALVE VV30B, a somewhat larger version if the 300B. The VV30 Factory price was in the beginning 125DM (60Euro) for private persons. These VV30B were very good quality. It is hard to imagine, it was not easy to sell then in those days. There was no internet, and the way to communicate was by fax, which at that time cost you 5 Euro per minute to some countries. Well, we think back, and we all say we should have done this or that, Just when I look back, I should have invested in a nice stack of those good old VV30's. On the other hand 60 Euro was a lot of money in 1995. I think truly NOS VV30 will sell good for 10x the price now. Some history of 300B that is!
All machines were self made, and or modified from existing machines. While at that moment, the classical tube industry was dying, the supply of old machines was very large. This was in the dark days where 40 ears of socialism had eaten up all resources, and now nothing was left but rotten buildings and demotivated people. In the middle of that, there were new branched of industry developing, while the communists and socialists had to let go and leave a mess. So that was a dynamic situation, where the old was making place for the new. Alesa Vaic managed to set up his small plant with money from English and Japanese investors. Sure he was a good sales man too.
Here you see the later brand name AVVT tube being tested. This is one 300B that was burning all day and night in the factory, demonstrating the 300B lifetime of the tube. I got Alesa wearing a pink short and a neck tie for this photo shoot, in 1998.
What you see here, is the normal was for 300B tubes, using light bulbs as load resistors, giving a stabile bias, and being a fuse at the same time. Also this is giving a quick indication if a tubes work good or not. A nice and classical method, used all around the world.
VAIC VALVE VV30B Curves, tested with Audiomatica Sofia tester
300B Mesh by AVVT (previous Vaic-Valve) VV30B original typewriter data sheets by Alesa Vaic.
WESTERN ELECTRIC PART 1.
Western Electric Factory, founded 1919 To go to the crossroad, exactly where the tower on this picture is, There is a thing called the Hawthorne effect, named after the location of this factory. This is elementary. In the main days of electron tube production, interesting experiments were done to find out how workers can be motivated to produce work of a better quality. The idea was to study this in detail, with graphs. They expected to end up with the required amount of light a person of a certain skill would need, to produce best possible work. This factory was nicely suited, due to many identical working rooms. At first they tried to use more brilliant lamps. . Indeed, this had a positive effect, and the investment payed off. They made graphs of the quality versus light intensity. They tried also other things that make people feel better. Like giving 5 minutes breaks, and try with or without food. If something had a positive result, still after some time the results always fell back to the old level. This was subject of a follow up investigation together with Harvard university and representaves of the national industry. It appeared the "care" for the workers caused the better quality. Not the improved conditions itself. The idea was then, to make this "care for your employees" a program to increase quality in a more permanent way. Managers were asked to make personal compliments to workers, in front of the others. The conversations were put on paper and studied. It went into the management classes of Harvard Business school as the "Hawthorne effect". Still valid today. It may seem nothing special now, but it was in 1930. So look at the empty parking lot above... Here the Hawthorne effect was discovered, and went into the school books.
The roots of the WE300B go back to company Gray and Barton, a telephone equipment manufacturer, and the company was re-named in Western Electric in 1881. The export branch of Western Electric was called Western Electric Export Corporation, which again was renamed WESTREX in 1942. In 1958 Westrex was sold to Litton. First tubes, without getter.
Pictures of early telephone amplifier, with no-getter tubes
Excellent schematic. Still recommended do to it this way, now 100 years later. First Barium Getter tubes.
This is the famous Sealex machine, also called a carousel. It is a masterpiece. It manufactures the tubes by machine, but needs more than one operator as you can see.
Burn-in before final testing.
The mother of the 300B is the 300A, both designed by Western Electric. I have not found specific information yet, what is the difference. However the following datasheet was valid for both types. Forget about the hand written markings in there. 300B tube description (old production xxx---1988) Production of WE 300B was stopped in 1988, and a last buy option was given to all. After the tube was off the market for some time, an American called Charlie Whitener, set up the production again, using all old tools and machines, retired employees, and old materials. In industry, with "materials" is always meant half-products, such as filament wire, etc. You will find various opinions of this in the internet, but I heard it often that the original old production is preferred by many. NOS or like NOS tubes if this production jumped over the 1000$ limit some ago, and everybody way screaming: Crazy.. Crazy.. Now as I write this, prices of 1500$ are seen on Ebay. There seems no limit in search for the Holy Grail and mother of all HiFi Power Triodes. They are very rare. Said to be much superior to the later retro build 300B, and virtually free of any quality problems whatsoever. ........... to be continued
WESTERN ELECTRIC PART 2
This is a nice marketing picture of the retro production tubes, unfortunately out of production since 2008.
Charles Whitener, is now the CEO of Western Electric Export Corporation. These little cards were added with later (retro) production of the WE300B. These apear to be real plots. I checked a few here, they are correct and correspondig nicely to the tubes that were added. However I do have a comment on the test result. If you look at the test data this (new) tube shows only 44.9mA instead of 60mA. There is general conception that a good tube may not be down more than 70%. So lower than 42mA is not a good tube any more. By itself the curves are healthy, so no problem. It is just the myth of the "PERFECT TUBE" I see not confirmed here. The plots show tubes of normally good quality, but to my opinion not the winner. First look at the other tubes:
NOTE - When I have time, I will also measure the EHX AND SOVTEK 300B with the Sofia. Just got mine recently.
SOME 300B CIRCUITS Specifications and maximum ratings as according to official Western Electric 300B tube data sheet
Click this picture, so read the complete Western Electric 300B data sheet. It has harmonic Distortion numbers for all harmonics, at each setting. Most probably, these distortion numbers are only calculated, though they do not say so they are measured or calculated. In the WE 205D data sheet, this is explained how to calculate it. |
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