Heinz Schmitz wrote in message
...
N_Cook wrote:

Where would they have come from ? some batch of other double tetrodes and
markings removed ? all Chinese script so scrubbed off ?

Rumors say, that some tubes from me-too-ers have been remarked
to appear as from a high-quality producer.

4 presumably ECC83 in a Laney (not originals) all test bad C/H leakage
and
bad/ low or marginally good gain.

To be certain, you have to eliminate the "presumably"
(by measurement?).

Not a trace of any marking , as low power
valves, presumably no marking originally. They look like any other ECC83,
no
bad cut metal/ broken mica or any other indication of bad manufacture.

Some ink seems to soften over time, so that even touching/handling
rubs the marking off.

Regards,
H.





measured on avo tester with settings as ECC83.
just tried looping ptfe tape around the envelopes and fingernail pressure
but not the slightest lettering appeared.
All the valves have an unusual cloudy appearance within the glass where the
leads go through, so presumably all the same batch/make despite different
impressed letter/numbers in the flat base glass sections of the valves. No
Mullard type tiny code numbers on the envelopes.


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