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1st AMP AL-811

W1MSG

Now W1MSG
May 9, 2010
499
18
28
MA
Well its almost my Birthday and with that being said a new AL-811 maybe here.

This will be my first amp and I have never even used an amp before.

I already have an LDG AT-600pro Tuner so I figure that would handle the power of the 811 easy enough and I dont plan to drive the snot out of it. I'll be using it with my IC-7000. Is there any special connections I will need to use this amp?

Thanks

Craig
 

You need a Relay buffer for the exciter line and the ALC line they make cables for these and MFJ makes a nice Relay buffer box. D an internet search on these items there allover the place.
 
This is what I bought and it works great. I was told I did not need the relay cable which has the ALC on it because the IC-7000 is max output of 100 watts. I had the cable well over a year with great performance.

Hope this helps.

AP
 
Oh by the way, How do you like the LDG AT-600pro? If and when I get my general I will need a tuner with higher watt rating than my AT-7000 tuner.

AP
 
Hmmmmm...... an amp rated for 600 watts pep and an auto tuner rated for 600 watts with a note about it being rated for 700 watts ABSOLUTE maximum power. Personally I wouldn't run that combination especially if the mismatch is rather high.It's kind of like driving your car with the tach on the red line all the time. Power ratings can go straight out the window when dealing with funky impedances.
 
I wouldn't use ANY tuner with an amp. That is why there are resonant antennas. A tuner is a crutch. You probably wont use the amp much anyway. Just not really needed all that often. :whistle:
 
I love the AT600, much better than my IT-100. Pretty quick tuning and I get 1.1 to 1.3 from 10m to 40m on the G5RV.

I really dont plan on cranking the Amp up, 500 watts is what I plan, nothing says you have to crank em for all you can get. My Mustang makes 535 HP at the rear wheels but we detuned it for 440 HP due to a stock bottom end on the motor so you can always back it down if needed.

Looks like Ameritron has a plug and play interface for like $60, should make it super easy.

Jury is still out, so far I have been able to work everyone I can hear and I get through some of the pile ups pretty well so we shall see ....

Thanks for all the comments and suggestions.
 
I wouldn't use ANY tuner with an amp. That is why there are resonant antennas. A tuner is a crutch. You probably wont use the amp much anyway. Just not really needed all that often. :whistle:

this artricle will explain about antenna tuners, and much more it is worth reading.

The Real SWR Page - Explained by WC7I - Will high SWR burn up my radio?

Broadcast stations use tuners, military communication facilities use tuners.

811A, nice amp but there may be better choices, four tubes is four time more to go bad. a pair of 572b will give you same if not more output, more rugged tube.

A single 3-500z will idle at 600 watts. the old saying, if you need more power, do not add more tubes, get a bigger tube.

The best transmitter in the world is only as good as the antenna it is connected to. The best investment in any station is the antenna system and the transmission line.
 
You just need simple relay attached to a RCA cable for the amp and your ACC cable on the other. Check page 21 of the Icom IC-7000 manual for the circuit. If you don't feel like building one, you can purchase them:

Icom IC-7000, 706 Amplifier Relay Cable WITH ALC - eBay (item 350273166629 end time Sep-27-10 11:01:18 PDT)

On those above, they stuff the relay inside the DIN connector and cut off all the unused pins in the connector to get it to fit. If you go that route, contact the guy first and ask him to make it with the relay in the cable section, with shrink wrap around it and NOT cut off the pins. That way you can solder wires to the other pins when you need to make use of the other pins.

I agree about being very careful with running 600 watts into that tuner with odd antennas. Most people need to use a tuner of some type if they operate on 75/80 meters (or lower) a lot. It's pretty difficult to get a reasonable SWR across the band.
 
This is why I love this place, all the great info and suggestions.

wavrider, I read that entire article and its Great. I had a pretty good idea about SWR and what it means etc but that really cleared things up alot.

I was pretty much talked off the ledge on getting an amp and then a local guy offered up a Amp Supply 1000 NT that he doesnt use anymore, it does need tubes and I guess they are notorious for the tubes going out. I can get it super cheap and he has a line on some tubes for it so I might give it a shot, think of it as a learning experience.

You guys Rock !

Craig
 
The AL-811 /My Review

Craig/W1MED: Greetings, glad your having such a good time with your new allocations.

I have own my AL-811(3 hole version) for quite sometime now. I purchased it used maybe 5 or more years ago for $325. She had a soft set of tubes plus a few scratches and scuff marks...but not really bad shape.

I think I am on my third set of " fire bottles". The first 2 sets were China made 811a's. The first set were made by the same factory as the Taylor brand, RF Parts sells. I pulled them when they got down to about 500w on tune-up on 75 meters with 50/60w drive.

The next set was made also made in China, the PENTA brand. They were said to be better, but maybe just a bad run. The glass melted on one of them a couple months(maybe 6 weeks) after the install.

The present set of tubes are the Svetlana(Winged "C") brand 572B's. I have found them to be very good and after at least a couple years still at 90%+ of full output.

The amp is easy to tune and operate. I load her up with about 25w for CW use using a straight key. When operating SSB... I get her close, then I quickly (5-10 seconds max) hit her with 50-60 watts.
I see from 6 to 700 watts depending on the band...(40m/20m) are a little better.
I have repaired or replaced nothing other than tubes since purchased...she does need one new meter lamp. I'll change that when ever she needs new tubes.
I did find she operates much better as described above with 240v source voltage vs. 120v.
Plate voltage was about 1650v on 120v...about 1750/1800 on 240v with much less sag.

Now to the tuner....I would suggest as others, going to something with a little more "headroom". Nothing rated at less than a KW/CCW.
I would suggest:
Dentron MT-2000A/ Heathkit 2040 or 2060/ Dentron Super Tuner/ Murch 2000/ their are others in that range. I do not like any tuner MFJ makes...MHO.
I run a Dentron/MT-2000A modified to a "Double L"...

The G5RV's are not a bad antenna for 20m, but a double Zepp or Ext. Double Zepp... or W8JK antenna will kick it's butt anywhere else!

I am presently using a pair of Double Zepp antennas(58ft each element) with 58ft spacing and "backfired" with 450 ladder line...I have used it for every band(75/40/30/20/17) everything but 15/10 meters...I had a 4 /Double Zepp version up with 34ft spacing(33ft elements) for a long time, but this present version works a little better on 75m than the other.

I'll put the 4 banger back up when I get couple more sections of tower installed. Then I'll have both.
Well more fodder to ponder...:LOL:
All the Best
BJ
 
Thanks BJ, just when I thought I was talked off the ledge, you have peaked my interest.

Well if HRO e-mails me back and they have everything in stock I guess i will be driving to NH today, this is getting to be a regular trip for me ...

On another note, just took a look at the AT-600pro manual again and it is rated at 700 watts maximum power input, so I guess if I am careful it shouldnt be an issue, the AL-811 states 600 watts output.
I am sure I will have a load of questions when I get it all set up and operational....

Craig
 
Last edited:
...then a local guy offered up a Amp Supply 1000 NT that he doesnt use anymore, it does need tubes and I guess they are notorious for the tubes going out. I can get it super cheap...Craig

how cheap is "super cheap"? ,..... less than $200 (minus the cost to retube it) i would hope.

i'm trying to remember, i think the 1000 No Tune had various tube configurations,..... 6me6, 6mj6, 6lq6.

i think i would be tempted to "pass" on it unless it REALLY!!!! is cheap
 
Well the Amp Supply price wasnt as cheap as I thought it was going to be. He finally said he would take $350 with no Tubes. So I have a brand new AL-811 sitting next to me.

I guess going new will be the best thing in the long run, warranty and all.

Took about an hour to get on the air with it, contacted 3 different stations. I was hearing 1 station at about a S3 to S4, tried to contact barefoot, but he wasnt hearing me, turned the amp on and made the contact with a 59 report back from him.

So I look forward to giving it a try on some pile ups ..


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