Hello all
I'm constructing a tetrode amp. and the filament transformer
I have has no centre-tap. I do not want to 'earth' one side
of the filament.,
Any suggestions as to how I can monitor the cathode current ?
(The HV- would normally be connected to the centre-tap of the
filament xfmr. and the cathode current metering between this
point and 'earth') One idea I had was to make an 'artificial'
centre-tap by connecting a low-value wirewound resistor to
each side of the filament, and take the HV- to where they join.
(checking that not too much filament AC current flows through
these 2 resistors) I would never ever monitor the current on
the HV+ side !
I seem to remember a circuit which overcame this problem - maybe
in an old RSGB or ARRL Handbook ?
Thanks - 73
Chris GM3WOJ/GM8V
<chris.tran@zetnet.co.uk>
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