> Hi all,
> After having frequented the towertalk list, i am
> new to the amps reflector. Well, wanted that
> extra power after the tower has been installed.
>
> Now i do have some stupid questions on Amps.
> I am not quite an experienced homebrewer. Especially,
> after that RF burn with a 100W rig when playing with
> apartment antennas, i am a bit shy. But willing to
> safely experiment .{ not yet on homebrewing a QRO amp :) }
>
> I am contemplating on an AL-811/AL-811H.
>
> 1) Is the AL-811H the same copy of AL-811, but
> has an extra matched tube.??
[Steve Katz] (WB2WIK/6): No, it's not.
> 2) Can i buy an AL-811 and then later, when i
> retube it, drop in a matched quad of 572B's to
> make it a AL-811H. I assume the 811 will have an
> unused tube socket.
[Steve Katz] (WB2WIK/6): No, the AL811 does not have an unused tube
socket. The AL811 and 811H do not use 572B's, they use 811A's. Only the
AL-572 uses 572B's.
> 3) I have been thru the eham.net reviews on the AL-811's.
> A lot of folks have given a big thumbs up for the Amp.
[Steve Katz] (WB2WIK/6): It has a good price-to-performance ratio
and there are certainly a lot of them on the air.
> What are the things i should keep in mind when looking out
> or testing an amp, if i buy used?? Would you recommend this
> for my first amp.
[Steve Katz] (WB2WIK/6): These are relatively heavy and subject to
shipping damage, so I would not buy a used amp remotely; if you want to find
a used amp, shop locally, so you can look at it, see it work, and pick it up
yourself. The AL-811 or 811H will work fine with your TS-440, although the
811 barely meets my criteria of a reasonable power increase. The TS-440
runs 100W out; the AL-811 will produce 600W; this is only a tad over 7 dB
power increase. I usually shoot for 10 dB, simply to feel like I've
accomplished something, but that's a personal issue. To increase power 10
dB requires a 1kW output amplifier, like the AL80B (or the AL572).
Personally, I think the AL80B is probably the best cost-to-performance
ratio amp on the market, since it not only nearly 3 dB more power than the
AL811, but also has an excellent peak-reading wattmeter/SWR meter built-in
(which the 811 does not), saving the cost of that (normally $100-$150)
accessory. And the meter works well.
> My setup has a TA-33 with the 2KW traps, a TS-440 exciter
> and a MFJ-969( 300W tuner).
[Steve Katz] (WB2WIK/6): Obviously, that tuner won't suffice for an
amplifier; however, if you stick with 20-15-10m, which the TA-33 is designed
for, you shouldn't need a tuner.
> Sorry about my stupid questions and i do appreciate your
> patience and help.
>
> 73's
> krish
[Steve Katz] 73, Krish -WB2WIK/6
> w4/vu2vku
>
>
>
>
> --
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> Problems: owner-amps@contesting.com
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