measures wrote:
>
>>I had also noted the grid current pinned the meter,
>
>? This is a fairly reliable indication of a parasitic oscillation c.
>120MHz. D-14 prevents destruction of the meter movement during the surge
>in grid current during the intermittent parasitic.
>
That is no proof of a parasitic. The grid current meter is in the return
path from chassis to B-minus, so a DC arc from B+ to chassis will pin
that meter with no RF involvement whatsoever.
73 from Ian G3SEK Editor, 'The VHF/UHF DX Book'
'In Practice' columnist for RadCom (RSGB)
http://www.ifwtech.com/g3sek
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