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[AMPS] Alpha 87A Owners! - I want to hear from you!!

To: <amps@contesting.com>
Subject: [AMPS] Alpha 87A Owners! - I want to hear from you!!
From: measures@vc.net (Rich Measures)
Date: Tue, 18 Nov 97 12:14:41 -0800
>> From:          Rich Measures <measures@vc.net>
> 
>> In commercial FM broadcast service, 8877s typically last 20,000 hours.  
>> 33 months in amateur radio service probably amounts to under 500 hours of 
>> use.   During the last ten years, I've tested a number of kaput 8877s 
>> that were removed from Alpha 77s.  Most of the failures were caused by 
>> gold sputtering from the 8877's grid.  
>
>More nonsense designed to sell magical "kits" . 
>
"nonsense", Mr. Rauch?  Are gold melt-balls on a cathode and gold 
blisters on a grid meaningless?  
-  According to Mr. Erhorn, the heat-dam problem lasted a bit over a 
year.  8877s have been manufactured for roughly 20 years.  I have seen 
the heat-dam problem in less than 5% of the kaput 8877s I have opened.  
It looks to me like the heat-dam issue is a combination of "passing the 
buck" and "any port in a storm".  .  .   Meanwhile, back at the avocado 
ranch, I find a high percentage of kaput 8874s and 3CX800A7s with 
gold-sputtering damage.  

There is nothing 'magical' about resistance-wire suppressors.  In Wes' 
measurements, the improvement (decrease in VHF-Rp) was only 40% 
over/under the W8JI suppressor.  The resistance-wire suppressor used in 
Wes' measurements could have easily been beaten out by a 200nH Ls, made 
from silver ribbon, and a 200 ohm Ls.  The fly in the ointment was 43 
watts of dissipation in Rs on 10m.  

R. L. Measures, 805-386-3734, AG6K   


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