[Amps] SPIKE Question????

[Dick Green WC1M]

If the 87A is shutting down without fault lights, it's a hardware fault.
When you restart the amp, the fault lights will indicate which hardware
fault caused the amp to power down. Many things can cause a hardware fault,
not just tubes. It's possible that one of the tubes is gassy and the
resulting arc fault is causing a hardware shutdown. I had that problem with
a new, defective tube once. However, unless you've been pounding on those
tubes, five years isn't terribly long. The tubes in my 87A are almost 10
years old and still going strong.

BTW, make sure the HI-LO switch is in the HI position. If you try to drive
it to full power with the amp in LO, it'll fault, though probably with a
software fault like excessive grid current.

73, Dick WC1M

> -----Original Message-----
> From: TED & JOYCE [mailto:k9huh at icss.net] 
> Sent: Wednesday, November 24, 2004 10:28 PM
> To: amps at contesting.com
> Subject: [Amps] SPIKE Question????
> 
> 
> Hi All,
>     Just found this reflector and hoping someone out there 
> may have an 
> answer short of new tubes to my problem.....Am running an Kenwood 870 
> into an Alpha 87a (about 5 years old)......On phone there is 
> now problem 
> with putting out full power...once I go to CW if I drive it 
> and output 
> is over about 5-600 watts it just completly shuts down.....NO 
> deffaults 
> lites  or anything.....Talked with alpha one time about this and they 
> told me tubes were getting soft which I am sure they 
> are.......Short of 
> putting 6Bills in to some new tubes is there any suggestions to get 
> around this intial volatage strike to the amp from the 
> exciter... and if 
> it is necessary to retube is there any way to avoid these  kind of 
> problems in the future......Yes before anyone replies it is 
> not in feed 
> lines antennas etc etc.........Same freq. same everything fine on SSB 
> intial spike on CW turns it off............Thanks and hoping to hear 
> from somebody that has been down this road 
> before................Best of 
> 73"s and a very Happy Thanksgiving too all...........
> Ted     K9HUH      "huh:
> 
> 
> 
> 
>