[TowerTalk] AL-1500 Amp Mod

[2]

>
>While at the Arlington, TX HamComm in June, I noticed that Ameritron had
>made a modification to the T/R relay in the AL-1500.   Specifically, they
>replaced the 3PDT mechanical unit with a pc board - electro / mechanical
>ckt.   

//   As I understand it, RF-actuated T/R bias switching is now in many 
MFJ/Ameritron amplifiers.   This allows the 8877's bias to rapidly switch 
between (linear) Tx and (non-linear) Rx modes during soft syllables of 
speech.  Since the 8877 is only linear when Tx bias is applied, this 
improvement is questionable.  
-  The Alpha 77 used RF-actuated bias switching and it generates bursts 
of adjacent hash during soft syllables.  The 77 also has a harsh sound on 
frequency.    

>Having replaced the relay twice in my AL-1500 I immediately became
>interested.   

//   Which contacts failed in the two relays?  Have you ever had an 8877 
fail in this amplifier?
tnx, Bruce

>  The next week I called their technical department and after
>a short time convinced them that it actually could be a field installable
>upgrade.  If you are an AL-1500 owner / user and are interested, call them
>and order part # 861-0453.   It costs about $35.00.   As this is not
>intended to be field installed, the instructions / prints that I got were
>all hand drawn and very hard to follow.  

//   Hand-drawn diagrams are incredible in the year 2001. 

>I have since created my own set
>using Microsoft word with digital color pictures included.   I offered them
>to Ameritron, but they were not interested.   

//  I have found that amplifier manufacturers don't like to be told 
nuttin'.  The Japanese have a word for it: "ringesho".  Translation:  
Even a logical idea is unacceptable if it doesn't originate from the 
company's CEO.

cheers, Bruce.  

>... ...

-  R. L. Measures, 805.386.3734,AG6K, www.vcnet.com/measures.  
end


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