Friday, June 30, 2023

Tube of the Month : The 6BJ3

Hi!

This month I have another TV Damper tube to present to you: The 6BJ3:



The 6BJ3 is a Compactron diode intended as the damping diode in the horizontal deflection circuit of TV sets. But like all TV dampers it also serves well as a rectifier tube.

The 6BJ3 has the same pinout as other Compactron dampers like the 6BE3 or 6CG3. For some background info on TV Damper tubes, see the 6AU4 tube of the month post. Also read the 6GE5 post for some info about the history of Compactron tubes. While the 6BJ3 shares the same 6.3V/1.2A heater with the 6BE3 it has lower maximum ratings for output current and peak inverse voltage. See the General Electric data sheet for details. Still plenty for use in preamps like my new Compactron preamplifier series and also for the power supplies of my 10Y line stage and D3a phono stage in the new chassis. In these chassis the low height of the 6BJ3 is beneficial and that's why I stocked some of them recently.

Let's have a look at what I got:



Starting with General Electric since they developed the Compactron tube series.









Next International Service Master who just rebranded tubes made by other manufacturers.




Internal construction looks the same as the GE. So surely made by GE.



Sylvania 6BJ3:




Again looks the same as the others, so Sylvania might have sourced them from GE as well.



And lastly some RCA 6BJ3:











Again suspiciously looks like GE made. 

A nifty little tube which will see some use in my preamplifiers. I mentioned above that the 6BJ3 is 'weaker' than the 6BE3. Here the two in comparison:




The lower maximum ratings allow a shorter plate and cathode. The 6BE3 also has a copper plate to enable the higher plate dissipation:



Best regards

Thomas





Friday, June 23, 2023

10Y Line Preamplifier in the New Chassis - Part 4

Hi!

The 10Y line preamplifier in the new chassis style is finished.



Both the power supply and preamp are fully assembled and completed with the wooden side panels.



Also full tested and ready to ship to their new owner.



Different finishes can be done on this version. Like different color side panels, side panels in metal and also different color anodisations.



Some close up pictures.







The power supply has a removable lid on the top to access the rectifier tubes.





Different feet are available, besides the stainless steel cones. The feet are exchangeable by the user.



The units can be placed side by side or stacked.



This preamp has 3 RCA inputs and one balanced input. The number of inputs can be chosen freely.



Both RCA and XLR outputs are standard as in all 10Y line stages.



If you want me to build a 10Y line preamp or anything else for you, send an email.




Best regards

Thomas





Friday, June 16, 2023

10Y Line Preamplifier in the New Chassis - Part 3

Hi!

In the meantime the assembly of the power supply is in progress. Here a few pics.



The power supply gets a chassis in the same new style with brushed aluminium front plate. The inside almost complete:



The rectifiers are mounted on the separate plate at the bottom:




Front and back panels mounted and wired up:



Ready for the first test run.




After the test the bottom plate and side panels will get attached.




Stay tuned for part 4 which will show the finished preamp combo. 

Best regards

Thomas


Sunday, June 11, 2023

10Y Line Preamplifier in the New Chassis - Part 2

Hi!

The assembly of the new line stage is in progress. Here a sneak preview



The side panels are still missing but this gives an impression of the final look:



The assembly is almost complete:



A few more steps and the first test run can be done. Stay tuned.

Best regards

Thomas