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Davewantsone · 8th Apr 2019, 8:54 pm

The only calculation was the initial which gave for a 455 ohm winding and a voltage of 30V was a current of 65mA, which was confirmed by the power supply output which measures output current and has a set current limit. This read 65mA. From the size of the winding I could tell 2 watts of power would not be enough to warm the LOpT. For the last 24 hours I have been applying 70V via a "Heath Robinson" collection of various power supplies and the current is now around 120mA. Which would mean the winding resistance due to it being warm has risen to around 580 ohms.The LOpT is now getting nearly 8 watts of power and is nicely warm to the touch. I will leave it for another 2 days and then report back on any progress.

8th Apr 2019, 8:54 pm	#45
Davewantsone Hexode Join Date: Dec 2011 Location: Wigan, Greater Manchester, UK. Posts: 291	Re: Pye V4 The only calculation was the initial which gave for a 455 ohm winding and a voltage of 30V was a current of 65mA, which was confirmed by the power supply output which measures output current and has a set current limit. This read 65mA. From the size of the winding I could tell 2 watts of power would not be enough to warm the LOpT. For the last 24 hours I have been applying 70V via a "Heath Robinson" collection of various power supplies and the current is now around 120mA. Which would mean the winding resistance due to it being warm has risen to around 580 ohms.The LOpT is now getting nearly 8 watts of power and is nicely warm to the touch. I will leave it for another 2 days and then report back on any progress.