Lane
>Rich,
>1. How did you rcv this information?
? the telephone, c. 11am, Wednesday. The call was from Fred, a friend
of Bob's. Fred told me he had a problem with the relay sticking in his
AL-1200.
>2. How do you know it is accurate?
? I did not inspect the AL-1500. nor did I test the kaput 8877s.
However, the info was incidental to a discussion about the ruggedness of
the 3CX1200A7 vs. heater-type tubes. Thus, I doubt that the story was a
plant. Bob, WB5UZR, and Fred can be found on 3853KHz LSB.
.
>3. How do you know he is not mis-tuning the amp or overdriving?
>
? ..Seven tubes seems unlikely. . Overdriving the cathode/ stripping
the cathode is a rare mode of failure in 8877s. . Testing the kaput
8877s would show the cause of failure. Hopefully, I will have the
opportunity to do that.
>I do NOT disagree with the idea that MOST of the Ameritron amps are of
>extremely poor RF design.
>
? An HF/MF 8877 amplifier with no VHF suppressor seems to be a
questionable design.
- cheers, Lane
>Ku7i
>-----Original Message-----
>From: Rich Measures <measures@vc.net>
>To: amps@contesting.com <amps@contesting.com>
To: <amps@contesting.com>
>Date: Wednesday, June 16, 1999 1:14 PM
>Subject: [AMPS] New World Record for 8877 Replacement
>
>
>
>?? An amplifier owned by Mr. Robert McFadden, WB5UZR has apparently set
>a new world record for 8877 replacement in one amplifier. Seven (7)
>replacement 8877s have been installed so far in his MFJ-Ameritron
>AL-1500 -- the one and only manufactured 8877 HF amplifier that does
>not utilize any VHF parasitic-suppressor whatsoever. As I recall, the
>old record was reportedly held by an 8-lander in Indiana whose AL-1500
>required six replacement 8877s. Some of the 8877s apparently failed from
>gold-sputtering.
>
>
>Rich...
Rich...
R. L. Measures, 805-386-3734, AG6K, www.vcnet.com/measures
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