The designation of the 76 line is
76a.... 2 tubes, stock xformer
76PA.... 3 tubes , stock xformer
75PAC... 3 tubes, hypersil xformer.
Maybe there was an 76 alone, but maybe the "a" means America..... Who knows?
And yet the grid can shoot up fast. 73
Charles Harpole k4vud@hotmail.com
> From: km1h@jeremy.mv.com
> To: apolloeme@live.com; mikea@mikea.ath.cx; amps@contesting.com
> Date: Mon, 12 Sep 2011 20:00:53 -0400
> Subject: Re: [Amps] Alpha 76a
>
>
> ----- Original Message -----
> From: "Patrick Barthelow" <apolloeme@live.com>
> To: <mikea@mikea.ath.cx>; <amps@contesting.com>
> Sent: Monday, September 12, 2011 3:00 PM
> Subject: Re: [Amps] Alpha 76a
>
>
> >
> > I received a 76A about 6 months ago, as a gift from a OOM who I helped a
> > lot when he was active. A 3 holer, that had been stored for some time, I
> > "gettered" it, slowly, bringing it back to life, without incident. On ALL
> > amps I have run, I am hyper aware and observant of grid current, in the
> > interest of long life, and note that Bob Wolbert has published a grid
> > overcurrent trip circuit for the Alpha, that might be wise to install.
> > While getting used to normal tuning dynamics of my New/old stock Alpha, I
> > was startled somewhat at the grid current dynamics. At how quickly the
> > Ig goes from very low values to very high values with small adjustments of
> > input power, and tune and load controls, even with a good amount of
> > loading. Perhaps this is "normal" for a 3 holer '76A but maybe it is
> > saying something about one or more tubes. Other than that Ig
> > sensitivity, the Alpha is the "AC Cobra 427 " of amps, IMHO. and with
> > winter coming up, if I operate QRO with it, I will not
> > heed a shack heater, or a fire to cook marshmallows.
> >
> > Best Regards,
> > Pat Barthelow AA6EG
> >
>
> Well thats a good analogy but like any fast revving high winder when they
> come apart it aint purty. I wouldnt put it anywhere near the 427 Cobra but
> more like a finely tuned Boss 302 or Camaro first generation Z/28; a lot of
> fire in a small package.
>
> Now if you want a 427 performance get an LK-800A or C with the 3CPX800A7's
> and the 3000V PS upgrade.
>
> That amp can do nasty things to a 5KW slug with 120-150W of drive.
>
> Carl
> KM1H
>
> >
> >
> >> Date: Mon, 12 Sep 2011 13:31:22 -0500
> >> From: mikea@mikea.ath.cx
> >> To: amps@contesting.com
> >> Subject: Re: [Amps] Alpha 76a
> >>
> >> On Mon, Sep 12, 2011 at 11:20:33AM -0700, ROBERT HARMON wrote:
> >> > Charles,
> >> >
> >> >
> >> > I agree 100%. The Alpha 76PAC is one of the best amps ever made, a real
> >> > workhorse. Like a Timex watch, "takes a licking and keeps on ticking" ,
> >> > with one caveat, as you indicated, watch the grid current.
> >> > I run mine hard all the time (and keep a watchful eye on the grid
> >> > current)
> >> > Remember the "brick on the key" advertisements for these amps ? My
> >> > favorite is the ad used in 1981 which shows the usual heading of " Key
> >> > Down, How Long ?" and instead of the normally used brick on the key
> >> > there
> >> > is a skeleton sitting there with his hand on the key. Now thats a good
> >> > amp ! hihihi
> >>
> >> Erm ... As long as he's not wearing a nametag that reads "Ross Hull".
> >>
> >> --
> >> Mike Andrews, W5EGO
> >> mikea@mikea.ath.cx
> >> Tired old sysadmin
> >> _______________________________________________
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> >
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> >
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>
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