>Rich,
>
>Thanks for your help.
>
you are welcome.
>1.- Where the 100 ohm supressor resistor should be? I can't locate it.
? Inside the suppressor inductor.
>2.- My english is limited. What do you mean with "hot-pot the tube"
? high-pot means high-potential (voltage) breakdown test. Leakage
should be less than 10ua at 8kV.
>3.- What a DMM means?
? Digital Multi Meter
>BTW: Is the a retrofit-kit for the al-80?
? yes
>Might it help to avoid future
>problems like this
>
? maybe. A parasitic suppressor retrofit kit costs $13.50. It is
guaranteed to improve stability or it costs you nothing.
>
cheers, Marcel
>
>
>
>
>>>> measures <2@vc.net> 04/12 8:25 p.m. >>>
>
>>
>>Hi !!
>>
>>I have been using my AL-80A for years without trouble. Sudenly, during
>>last WPX, the amplifier stoped because thes fuse blowed. After restoring
>>
>>the fuse I observed that the 3-500Z showed blue color (gas?) at top, so
>>I replaced the tube as well.
>
>? A blue glow On the glass is ok - A blue glow between the anode and the
>(grounded) grid indicates a bad seal. .
>
>>No other symptom and all components seemed
>>to be intact
>>
>>When starting with the new tube i observed the grid current and ip
>>current indicators going full scale when transmiting with very low
>>power. The wattmeter shows normal output power.
>>
>>After looking at the reflector I replaced the 1n4007 diode because it
>>solved the problem when experiencing similar situations.
>
>? This suggests that there was some kind of temporary glitch.
>
>>After this ip
>>current indicator goes full
>>scale even if I don't transmit (Grid meter indicates zero). If I apply
>>normal drive the grid current and ip current indicators go full scale
>>again. The wattmeter shows normal output power.
>>
>>Any idea?
>>
>? I would:
>1. test the accuracy of the meters with a DMM.
>2. high-pot the tube.
>3. measure the actual resistance of the 100-ohm suppressor resistor.
>
>cheers, Marcel
>>
>>
>>
>>
>>
>>
>>--
>>FAQ on WWW: http://www.contesting.com/FAQ/amps
>>Submissions: amps@contesting.com
>>Administrative requests: amps-REQUEST@contesting.com
>>Problems: owner-amps@contesting.com
>>
>>
>
>
>- Rich..., 805.386.3734, www.vcnet.com/measures.
>end
>
>
>--
>FAQ on WWW: http://www.contesting.com/FAQ/amps
>Submissions: amps@contesting.com
>Administrative requests: amps-REQUEST@contesting.com
>Problems: owner-amps@contesting.com
>
>
>
- Rich..., 805.386.3734, www.vcnet.com/measures.
end
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