>
>> >The switch is the toughest component to find. I've worked weeks on
>> >this.
>>
>> ... and he still does not realize that RF needs cooling air. Curiously,
>> Heath had this figured out 30 years ago.
>>
>> end
>>
>> - Rich..., 805.386.3734, www.vcnet.com/measures.
>
>...and Rich still thinks it's parasitics!
We are talking about overheating of closed bandswitch contacts from HF
circulating current. From an owner "My brother and I also own an
AL-1500. I follow the discussion about AL-1500 on the reflector. The
amplifier, owned by club, is cca 4 years old and
mostly used during the contests. Last year I replaced the output switch
(some contacts were overheated). The part of the output coil (L1 on 10m)
also dissipates too much power. We solved this problem with additional
side
blower and "hole" on the top of the cover (above the filter).
By my opinion,the output tank is not well optimized since the efficiency
is
between 50 and 55 %.". .
>Curiously everyone else had it
>figured out it isn't parasitics years ago.
>
everyone else?
[chortle]
- Rich..., 805.386.3734, www.vcnet.com/measures.
end
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