Is it possible to hook up 6c33 plate in parallel

[100db]

Hello,

Newbies questions to you guys.
If I want to hook up both "plate" of 6c33 to the output transformer in parallel and this tube has only one Cathode.

- Is it possible to do this with out harming the tube ?
- If yes, which connection do I need to change in this schematic and what is the proper value on the primary side of Output transformer ?

.... and the last question, is 6J5 still able to drive them ?

Not sure if my explanation is clear enough, sorry for poor english.

[tubetvr]

Hi,

The 6C33C consist of 2 triodes in the same envelope but they are connected in parallell internally. There is no way to separate the 2 triodes from each other to use it as 2 triodes. There are 2 separate heaters and the tube can be powered with either one or both heaters the performabnce will be much less when using only one heater so use both.

A 6J5 is enough to drive a 6C33C, the Miller capacitance is about 100pF and a 6J5 will have about 5kohm output impedance which will give a -3dB point of ~300kHz

Recommended load impedance of 6C33C is 600 ohm and operating point of 220V and 200mA so you schematic is spot on, I believe it is one of the original ones published in MJ in Japan.

Regards Hans

[Alain Dupont]

100db,

On the socket there is only one Anode pin in 4

It's just because you heat with the 2 heaters that you get the maximum
of power from this tube, if you use only one of the heaters you'll work
with half the tube...

Heaters are on Pins : 1 to 2 and 6 to 7
Kathode on pin 3
Anode on pin 4
Gate on pin 5
Thats a total of 7 pins.

PS: I am working on the http://www.valvediy.com/simplexpg1.html

Regards.

Alain.

[100db]

Hi Hans / Alain

Many thanks for your advise !
Actually one of my best friend asked me to post this thread for him, and I think he get his answer now

PS : Just visit your link, Very nice work !
My friend should learn a lot from your site ( also for me ).


best regards
Ball

[Alain Dupont]

100db,

Thanks, but for the amplifier on the link, it's from Ari Polisois !

I am building a "Complex" version with 2 sets of separated power supply's ;
one for each channel, and each individual PS's are MosFet regulated from
a 330VA toroid transfo.

2 Toroid transfo's 330VA
and for each:
1 alim for B+ 200 to 270 Volts DC at 0.9A Plate 6C33C-B
1 alim for 6SN7GTB to 420 Volts DC at 80 mA Driver
1 alim for 6SN7GTB to 200 Volts DC at 50 mA Preamplifier
1 alim for 6C33C-B heaters to 12.6VDC 3.3A
1 alim for 6SN7GTB heaters at 12.6VDC 1A Driver
1 alim for 6SN7GTB heaters at 12.6VDC 1A Preamplifier
1 Alim for LCD display 5VDC at 0.5A

I just finished the 2 walnut chassis!



Alain.