Weird question i know.

The tubes that need replacing in this Cembalet keyboard have their
lettering completely worn off. I'm pretty sure they are ECH81 and a
V400, but the V400 number makes no sense. It's a very strange looking
tube as well There is a top andd bottom heater coil, with two grey
boxes attached to the rest of the pins. When i tap this one with the
instrument turned on i get wild RF and tonnes of noise .. So it needs
replacement.

Anyone ever worked on one of these? Have schematics or a service manual
sitting arround?

Please help!!!


Thanks
Nick

"nmm"

The tubes that need replacing in this Cembalet keyboard have their
lettering completely worn off. I'm pretty sure they are ECH81 and a
V400, but the V400 number makes no sense.


** Very likely a CV455.

Same as a 12AT7

The one on the left in the pic of the chassis - right ?





......... Phil

"Phil Allison"



The one on the left in the pic of the chassis - right ?

http://cgi.ebay.com/Hohner-Cembalet-...cmd ZViewItem




........ Phil

Phil Allison wrote:
"Phil Allison"



The one on the left in the pic of the chassis - right ?

http://cgi.ebay.com/Hohner-Cembalet-...cmd ZViewItem




....... Phil

Yes, the "V400" ( or at least the one that the only thing i can read
on the side of the tube, that says V400 ) is on the left side. The
ECH81 is to the back on the right side. How can you tell that it's a
12AT7?

That one in that ebay auction was in really good shape, mine is in need
of some help, I've replaced all the pluckers, cleaned out all the
rotten foam dampers.. and am now trying to get the
electronics to work again.


Thanks!!

nmm wrote:

The tubes that need replacing in this Cembalet keyboard have their
lettering completely worn off. I'm pretty sure they are ECH81 and a
V400, but the V400 number makes no sense. It's a very strange looking
tube as well There is a top andd bottom heater coil, with two grey
boxes attached to the rest of the pins. When i tap this one with the
instrument turned on i get wild RF and tonnes of noise .. So it needs
replacement.

You sure it's not a thermal delay relay? For soft turn-on?
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

Phil Allison wrote:
"nmm"

The tubes that need replacing in this Cembalet keyboard have their
lettering completely worn off. I'm pretty sure they are ECH81 and a
V400, but the V400 number makes no sense.


** Very likely a CV455.

Same as a 12AT7

The one on the left in the pic of the chassis - right ?

........ Phil


From the way my tube looks, there might be a letter before the "V", but
it's definately a "400" after it. There is a "KB/" and what looks like
a "4" after that but it might be a "1".

No-one seems to have the schematic for the tube version. I found a
schematic for the transistor version, but that's no good to me.

"nmm"

** Very likely a CV455.

Same as a 12AT7

The one on the left in the pic of the chassis - right ?

From the way my tube looks, there might be a letter before the "V", but
it's definately a "400" after it. There is a "KB/" and what looks like
a "4" after that but it might be a "1".



** A CV4004 is a 12AX7.

Bound to be one or the other.

Just get some and PLUG THEM IN !!!




...... Phil