Hello, Tony

Sorry, I can't help you find that tube tester bias pot.

One thing, though:
I know the TV-7 manual gives voltmeter readings
versus bias pot settings, set up using a military DC voltmeter
of only 1K Ohm/volt sensitivity.
The available voltmeter ranges were 0 to 10V
and 0 to 50V, so the load across the bias pot
was either 10K or 50K depending on the voltage
to be measured during calibration of the bias pot.

I assume the I-177 was also intended to be calibrated
using a DC voltmeter of that sensitivity.

73,
Ed Knobloch


depending Antonio Vernucci wrote:
The I-177 tube tester has a very unusual non-linear wire-wound potentiometer.

Does anyone have an idea on whether any surplus store could have it on sale?

Thanks and 73

Tony, I0JX

Thanks for the info. However, for the I-177 I have seen no calibration =
procedure. I guess everything relies on the fact that the potentiometer =
has the specified response.

73

Tony, I0JX

"Edward Knobloch" ha scritto nel messaggio =
news:geBOd.30844$QS5.21636@trndny06...
Hello, Tony
=20
Sorry, I can't help you find that tube tester bias pot.
=20
One thing, though:
I know the TV-7 manual gives voltmeter readings
versus bias pot settings, set up using a military DC voltmeter
of only 1K Ohm/volt sensitivity.
The available voltmeter ranges were 0 to 10V
and 0 to 50V, so the load across the bias pot
was either 10K or 50K depending on the voltage
to be measured during calibration of the bias pot.
=20
I assume the I-177 was also intended to be calibrated
using a DC voltmeter of that sensitivity.
=20
73,
Ed Knobloch
=20
=20
depending Antonio Vernucci wrote:
The I-177 tube tester has a very unusual non-linear wire-wound =
potentiometer.
=20
Does anyone have an idea on whether any surplus store could have it =
on sale?
=20
Thanks and 73
=20
Tony, I0JX