>
>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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