[Amps] AL-80B questions

[dj2001 at mn.rr.com]

I currently have a AL80A, purchased used.  It still has the original 
tube, the amp sn is 0156 so it's an old one, perhaps 15 years or more 
old.  It runs good with 70 watts of drive I get about 800 out, I have 
had it up to 1100 out for a short time to get the tube nice and hot, 
I don't normally run this amp that hard, some do.  I don't think this 
amp has any parasitics, but I have not tried this amp yet on the 
higher bands, 15,20.  Don't have the ten meter conversion yet, by the 
way anyone know whats involved to make the AL80A work on ten?  I did 
have to replace a resistor in the Hv meter circut, it had changed 
value from 1.5 meg to 2.8 meg.  I also installed a step start circut. 
This is a nice amp for the money and it will get within a couple of 
db of the legal limit, SSB.  I don't think I'd use it for rtty though.

Prior to the AL80A I had a TenTec Titan, which I purchased new and 
had it for 12 years.  It still has the original tube and still puts 
out full rated power plus.  I have never had a pop or anything that I 
could say was a problem in that amplifier, no parasitics.

Prior to that I had a used Alpha 76CA, it also put out the full rated 
power plus and I had that amp for several years, never any hint of a 
parasitic or any problem of any kind.

Prior to that I had a TL922 which I  purchased used from another ham 
here in town, again never any hint of a parasitic.  The only problem 
I had with the 922 was that big clunky changeover relay, I had to get 
in there and clean the contacts a couple of times.  This amp I was 
always a little leary of though, don't know why, maybe it was that 
big relay.  A very cool running amp though and put out a lot of power.

Prior to that I had a L4B by Drake, again purchased used, never a 
hint of parasitics or other problems although I did have to replace 
the tubes right off the bat as they were soft, I knew this when I 
bought it, the guy was honest and told me they needed replacing, the 
price was right as I recall.  A local purchase. The cabnit rattled 
and buzzed though so I lifted one corner and stuck some paper under 
one foot, that quieted it down some.  I had this amp for about 3 
years.

Prior to that I had a used SB200, (ho-hum) never a hint of 
parasitics, no problem of any kind with that amp, although it only 
put out 500-600 watts, but that was my first amp and I may not have 
been driving it very hard as I am a rather conserviative operator 
especally back then.  In all fairness I never operated on the upper 
bands with this amp, so I don't really know if it had any weirdness 
or not.

Now after having all those amps and no problems you can see that I am 
skeptical as to amplifier instability claims.  If you're careful 
about tuning up and don't grab the band switch instead of the tuning 
knob (TL922), keep the thing loaded a little bit heavy I think and 
don't try to load up a ground, also keep your antenna and feedline in 
good condition, you should be ok.  I don't know whats wrong with your 
freinds amp, I  hope he gets it resolved soon, it seems to be going 
thru tubes like crazy.

By the way out of all the amps I've had over the years the Alpha 76CA 
was my favorite.  Something about those older Alphas that I liked. 
The tubes are pricey though, $400 or so each!!

Does this help?  I know you wanted slightly different answers, but I 
couldent help telling my story.

73
Dale K9VUJ




>  Therefore, I'm curious to know if there are others on this 
>reflector who've experienced similar problems (any brand amplifier) 
>that have been successfully solved with the AG6K ( or another design 
>) VHF supressor. To round out the study, one would also need to know 
>if someone had installed such a thing and found that it *did not* 
>solve the problem it was intended to correct, or if it caused other 
>problems.
>
>I wonder if Amperex is making master cylinders?  I just replaced it 
>on my Volkswagen for the 3rd time this year.
>
>
>Sooooo much to learn..... Sooooooo little time
>
>
>Kind regards all
>
>Randy DuCharme (AD5GB)
>--
>Microsoft is NOT the answer
>Microsoft is the question and the answer is NO!
>
>Proud to be 100% Microsoft Free