Monday, December 31, 2018

Happy New Year!

Hi!

Yet another year is coming to its end. Time for a recap.





2018 has been great. Probably the biggest new development on the amplifier side was the rise of the 46.




Despite the extremely low power output of just over 1W surprisingly many people commissioned the build of such an amplifier. A total of 6 pairs of mono blocks built! All of them with 46 as driver. The first set of 46 drive 46 monos proved the concept and led to more builds like that up to the full silver version and even a differential version using 4 46 tubes per channel and almost tripling the output power.The latest are a set of 4 chassis in landscape style:




These will be shown in detail in an upcoming post.






2018 also had some exciting events and shows. Like the opening of the Hong Kong show room and the Hong Kong HiFi Show as well as the Munich High End. I will exhibit again at both these shows in 2019 and probably one or two more. There are plans to move the Hong Kong show room to a better location, and if things go as planned a new showroom will open in Singapore next year.




In 2018 I finally launched a separate product website, www.vinylsavor.com which gives an overview of amplifiers which can be ordered and their prices.




At Deutsche Elektronenröhren Manufaktur GmbH we moved the ELROG ER801A and ER50 into regular production.




And we launched the first new tube development which was not based on an existing type, the ER887, a directly heated driver tube for the ER845.




Feedbacks from users of these tubes have been excellent. Especially the ER801A was tested by many owners of a 10Y Linestage.




Since our tubes fulfill and exceed the specs of a 801A which is an uprated version of the 10Y, ER801A was chosen as tube designation rather than ER10Y.




This opens the question if i shall continue to use the 10Y moniker for my directly heated linestage or start to call it 801A Linestage.




In case you wondered about the first photo, it shows the new plate structure of our molybdenum tubes. The plate has laser cut slots now.




For 2019 more new ELROG tube types are planned. The first being the ER888 which is the molybdenum version of the ER887 and meant to complement the ER284.




This brings our portfolio to 11 different tube types. More about the ER888 in an upcoming post.




Thanks to all customers, partners and the staff at Deutsche Elektronenröhren Manufaktur for a great year!




All the best wishes, health, success and joy to your families and yourselves!

Thomas

Sunday, December 23, 2018

Seasons Greetings

Hi!

Seasons Greetings with some nice tube glow.




A newly finished set of 300B tower mono blocks.




ELROG ER801A driver tube on the left and ELROG ER300B output tube on the right.



Finished with gold anodised metal plates in smoked eucalyptus wood.







Happy holidays !

Thomas



Sunday, December 16, 2018

Tube of the Month : The 12AV5

Hi!

Last year the December tube was a beam pentode designed for horizontal deflection service in TVs. So let's have a look at a similar one this year: The 12AV5.




Like the 6FW5 shown last year, the 12AV5 makes a nice pseudo triode when the screen grid is connected to the plate.

It is also available as a 6.3V heater variant (6AV5) but I only have 12,6V versions. The 12AV5 has an Octal base and no top cap. The pinout is shown on the left. It has a rather low maximum plate dissipation of 11W.  So the maximum power which can be extracted from it in single ended triode service is 2-3W. These TV tubes can take some abuse and I would not be scared to run it right at the allowed limit. It would probably make a nice low cost alternative to the 45. For the complete technical specs, see the General Electric data sheet. Especially the 12,6V variant can be easily found for cheap. So no need to complain about the rising prices of NOS tubes. If you are on a budget, take a side step off the main stream. As aways let's have a look at the triode connected plate curves:




Here some 12AV5 made by Raytheon:





A nice chubby little tube.







For just 11W dissipation the plate looks massive.




Some close ups:







CBS 12A5GA:







General Electric:







For examining the internal construction, this one has to die:




Removing the glass:






Clipping off the base:






Heater wire partially pulled out of the cathode sleeve:





The heater:




The plate:




Cathode, grids and beam forming plate:






Removing the beam plate:









Separating cathode and grids:




The cathode:




Screen grid, graphite coated to increase heat dissipation:




Control grid, gold plated to decrease secondary emission:




Those TV tubes were well made and produced at a time when tube manufacturing technology was very mature.




And lastly some photos of the tube in operation.






Best regards

Thomas