Rich Measures wrote:
>>>? the R-sups in the 922 receive cool forced air and they are virtually
>>>HF-shorted by silver straps. Does it seem likely that lower-band RF
>>>could damage these resistors?
>>
>>This brings us back to the old problem that we never know the condition
>>of the resistor (and/or tube) immediately before it failed. Was it still
>>like new, or had it already deteriorated way out of specification? Just
>>because the component finally failed on 80m, it doesn't mean that all
>>the damage was done on that band.
>>
>? An intermittent push-push vhf parasite is typically so brief that it
>causes no external damage to R-sup. Instead, the damage is internal,
>and, as such, can only be discovered with an ohmmeter. However, damage
>from 10m fundamental energy always causes visible damage.
>
But that still doesn't answer the question. Nobody checks until *after*
the amplifier fails.
73 from Ian G3SEK Editor, 'The VHF/UHF DX Book'
'In Practice' columnist for RadCom (RSGB)
http://www.ifwtech.demon.co.uk/g3sek
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