6C-A10 and 50C-A10

ask your general tube related questions here

6C-A10 and 50C-A10

Postby EWBrown » Fri Oct 23, 2009 5:32 pm

These hefty (30W PD) power triodes from Mitsubishi look like some "contenders" for aSET or PP amp:

http://frank.pocnet.net/sheets/084/5/50C-A10.pdf

These have been mentioned in passing before, now we have some usable data for them.

The basics:

Filament: 6.3V @ 1.5A ; 50V@ 0.175A
PD: 30W Max
IP Max : 200 mA
VB+ max: 450VDC

Class A amplifier:

VP: 250V
VG = -22V
IP: 80 mA
gm: 14 mA/V
RP: 620 ohms
mu: 8
Plate load: 1500 ohms
PO: 6W @ 7.5% THD

Duodecar base:

Filament: 1 + 12
Cathode: 10
Grid: 5 & 9
Plate: 3 & 7



/ed B
Real Radios Glow in the Dark
User avatar
EWBrown
Insulator & Iron Magnate
 
Posts: 6130
Joined: Wed Mar 19, 2003 6:03 am
Location: Now located in Clay County, NC !

Postby sorenj07 » Fri Oct 23, 2009 6:12 pm

Yes, but where on earth do we find them? (feel free to PM me to keep the answer out of Google's reach)
User avatar
sorenj07
KT88
 
Posts: 923
Joined: Tue May 02, 2006 2:39 pm
Location: Boston, MA

unobtainium ?

Postby EWBrown » Fri Oct 23, 2009 6:32 pm

Hi Soren

That's what I've been wondering... As they used to say about 50 years ago, "that is the $64,000 question".

They are used in Luxman amps, if that is of any help.

I've been doing some rather low profile searching...

/ed B
Real Radios Glow in the Dark
User avatar
EWBrown
Insulator & Iron Magnate
 
Posts: 6130
Joined: Wed Mar 19, 2003 6:03 am
Location: Now located in Clay County, NC !

Postby soundbrigade » Sun Oct 25, 2009 12:12 pm

Regarding places where you propably will not obtain a tube or two, I posted some links in the Compactron thread.
Regarding schematics, well, not that easu to find but here are some I find interesting:

50CA10 SE O/P
50CA10 Se I/P
50CA10 SE PSU

50CA10 SE

50CA10 SE

PP w 6AN8

PP according to YS-Audio

PP Luxman style

MQ60

PP w 6DJ8

This is how my 50CA10-SE looked like.

Image
Magnus

"It is always more difficult to fight against faith than against knowledge."
User avatar
soundbrigade
KT88
 
Posts: 1499
Joined: Mon Jan 28, 2008 4:57 am
Location: Little Paris, Sweden

Postby soundbrigade » Mon Jan 04, 2010 12:47 pm

I have just ordered (the last) two 50CA10 from a Chinese shop. I will "soon" start a project using THIS SCEMATIC. I've got all components apart from some electrolytics and a suitable chassis.
Magnus

"It is always more difficult to fight against faith than against knowledge."
User avatar
soundbrigade
KT88
 
Posts: 1499
Joined: Mon Jan 28, 2008 4:57 am
Location: Little Paris, Sweden

Postby EWBrown » Mon Jan 04, 2010 1:59 pm

6DT8 (and 12DT8) have identical operating characteristics as 12AT7 / ECC81 / 6021, except for teh filament connections (9AJ vsd 9A basing).
And IIRC, 6267 is EF86 or very close to it. 6DT8 and 12DT8 were the slightly cheaper TV or FM tuner version of 12AT7s. Don't know if they have an ECC8* or 6H** equivalent.

At a glance, the 50CA10s look very similar to 6550s or EL34s, from the outside.

Maybe the tube manufacturer ran off some modified EL34s with only the control grids, and the optional 50V filaments. And, of course, the different basing (compactron vs Octal).

Looks like an interesting project. What would be the best OPT primary impedance for the PP amp? I'd SWAG that you could use 6.6K a-a for these.

Just don't fuse the AC line neutral like they have in the schematic...
/ed B
Real Radios Glow in the Dark
User avatar
EWBrown
Insulator & Iron Magnate
 
Posts: 6130
Joined: Wed Mar 19, 2003 6:03 am
Location: Now located in Clay County, NC !

Postby soundbrigade » Mon Jan 04, 2010 2:59 pm

I got a pair of 6K6 trannies a few days ago. They aren't the most perfect but with the bell ends that came with the trannies they will look smart.
Of course I hope they are real 50CA10.
Here's one of the mails the buyer sent me:
I 2 years ago I still have approx 100 pcs original LUXMAN 50CA10 in stocks, but..after the Chinese factory dis-continued on production, all the 50CA10 tubes are become very rare and hard to find. I have asked the Chinese factory to make the 50CA10 for me, but the reply is the price is US$30 each and the minium order is 10,000 pcs to start with, do you think its wise to spend US$300,000 for one item of tubes?


A few yeras ago there were tubes to be found in Germany, Holland, England, Italay and I think I saw them i France as well but most were sold at 100 EUR each.
Magnus

"It is always more difficult to fight against faith than against knowledge."
User avatar
soundbrigade
KT88
 
Posts: 1499
Joined: Mon Jan 28, 2008 4:57 am
Location: Little Paris, Sweden


Return to tube 101

Who is online

Users browsing this forum: No registered users and 1 guest