converting EF86 to take 12AX7

[fdegrove]

Hi,

Yup...I quite like the AZ myself, the black plate one in particular.
Requires more heater current IRC.

National Electronics,

He, he, guess who that company belongs to?

Right, the same b*st*rds messing with tubes...
Never saw an almost perfectly disguised Chinese KT88? Look no further.
Not that they're the only ones anyway...

Ah, well...

Cheers,

 

[cogsncogs]

That figures! I have six of them, they seem to be built pretty good and are quiet not like some AT7's and AX7's I have. It says made in Germany on them but who knows. Maybe the closest they came to Germany was when they flew over here en' route to the US! hehe!
225 mA @ 12.6V 450 mA @ 6.3V heater current. 450mA that's your standard small signal TV tube heater current. Heater warm up time controlled for the A version.

Wayne

 

[fdegrove]

Hi,

12AZ7As made in Europe?
Not that I know of, nah...never.

You can tell if it's made in Europe, there should be a small plant code plus date code somewhere close to the bottom, acid etched in the glass.

The heater current seems to match the 12AZ7As but that doesn't tell much anyway.

Cheers,

 

[cogsncogs]

plant date code

There's a code on the very bottom by the pins of the tube but it's molded into the glass not etched. T and a one or two digit number underneath the T but reversed as read from the outside. Got a frosted bottom tho. Hmmm it's painted right on the glass Made In Germany. Here are some codes painted on the glass: 363A, 83781, 8706. The date and code on the box: DLA900-87-W 2141, 2/87 NATL etc. You never know nowadays what ya got. Prob German made in China!

Right, the same b*st*rds messing with tubes...

Richardson Elect. Ltd.?

Thanks
Wayne

 

[fdegrove]

Hi,

There's a code on the very bottom by the pins of the tube but it's molded into the glass not etched.

No idea where that's done like that but definetely not in Europe.
Code that's painted on the glass is pretty meaningless unless it's real, ayone can silkscreen on glass, acid etching is a different ballpark.

Richardson Elect. Ltd.?

Cheers,

 

[Flee]

Does anyone have a schematic to the Psilogram HL-86? I purchased one awhile back and it did suit my needs to sub a 12ax7 for an ef86 however, the construction was made with glue and the the heat from the amp melted the device. I had to destroy the guts digging it out of the chassis. I would like to resurect the devive but the designer will not answer my emails.

Regards