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Sinewave · 5th Nov 2019, 8:51 pm

Hi Bill, that's interesting, thanks for that, something for us to think over.

RMS certainly does seem more likely in that case.

At the moment with the output set to full, RMS output with 'set carrier' fully clockwise is 2.4v RMS, that's measured by a scope which will have a high impedance output. If I short across the scope with a 50ohm terminator it'll drop to 1.17v RMS.

'Set carrier' fully anti clockwise is 7.2v RMS no load and 2.9v RMS with a 50 ohm across it.

Of course the output is EMF, which will be a voltage with no current flowing, so perhaps that is somewhat right.

I wonder if adding the thermocouple changes those readings?

5th Nov 2019, 8:51 pm	#81
Sinewave Octode Join Date: May 2016 Location: Oxfordshire/Bucks borders, UK. Posts: 1,604	Re: Marconi TF144H/4S Hi Bill, that's interesting, thanks for that, something for us to think over. RMS certainly does seem more likely in that case. At the moment with the output set to full, RMS output with 'set carrier' fully clockwise is 2.4v RMS, that's measured by a scope which will have a high impedance output. If I short across the scope with a 50ohm terminator it'll drop to 1.17v RMS. 'Set carrier' fully anti clockwise is 7.2v RMS no load and 2.9v RMS with a 50 ohm across it. Of course the output is EMF, which will be a voltage with no current flowing, so perhaps that is somewhat right. I wonder if adding the thermocouple changes those readings? __________________ Avometer, vintage Fluke and Marconi collector. Also interested in vintage Yaesu and KW.