Will Matney wrote:
>Bill,
>
>We used to use a NE-2 as a tuning indicator. On a KW (about 1800 watts PEP) we
>took two 10 pF ceramic disc caps and seriesed them (5 pF), then hooked one end
>to the Load C, and the other to a leg of the neon bulb. The other end of the
>neon bulb was left unconnected. As the power raised the bulb grew brighter,
>and brighter yet on modulation. On smaller amps, we used a 10 pf to Load C
>(300-500 watts). I wouldn't recommend using this though over a good wattmeter
>to tune by. The same method can be used to sniff parasitics like Rich
>mentioned by using one leg of the bulb on the probe tip and the other
>unconnected. If there's any RF when the amp is idle, it will show it quickly.
>You can mount the bulb on the end of a wood dowell rod, or piece of plastic
>rod to make the probe up. Just be safe around that plate voltage.
>
>
>
I should look at the schematic for my Drake 2-NT - it has a neon bulb
for "tuning" - brighter is better.
--
73 Jason N1SU
Jason Buchanan - Boxboro, MA
Website: http://n1su.com/
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