you will find that the max output is also where the plate dips and the load maxes, you tune for max output then drop the input  for your required output.

thw 300 watt tuners Vectronics, MFJ etc can all handle a max of about 300 watts into a resonant load.  if you have a big mismatch, they will arc at 300 watts. you will probably want to remove the tuner from the curcuit or only run the amp into a dummy load, then switch it to the tuner/antenna when the power is well below 300 watts.

another handy thing to have is a dual cross needle meter for swr/power. you don't really have the time to push in and set then pull out and check when tuning your amp.

also make a matrix on paper for tune positions. like if you tune low, middle and high on 20 meters it would be:

3b5   3b7 and 3b9

with 3 being the first cap and b is the inductor setting and  the 5, 7, 9 is the other cap.  

do this for each band and yiou can pretty much get darn close to start when changing bands.


also the 811 and the 811H are basically the same exact radio with the H having 1 more tube in it. most every thing else is the same.  I have owned several 811's and 811 H's over the years..

if you want to run power, you need to upgrade all the components in the system. rg58 coax may arc at 500 wwatts, and 8x will arc at under a KW  with a high swr. so rg 8u or better is needed, and the tuner needs to be bigger etc.

I did not know you could not buy 811's I have a dozen or so over the years as spares, and I think you can go to ameritron and order a set of 3 for $60.

a new set of tubes is $60 for 3 of them (811's) so you would probably save more by getting spare tubes.  BTW don't bother to switch to 572's min an 811. there is no way to get more output from the amp as the power supply is the same. and if you don't spend 3 hours tuning up, the 811's will last for ever.

the real weak point is the filter caps and dropping resistors.  One of the resistors will change due to heat and they use four 400 volt cap and the amp runs at 1600 volts. so one small change in the resistors will eat caps, but parts to replace both are about $30 shipped.

 it is a good and solid amp and if you don't try to get every last erg out of it it will last for ever.

just for fun ask some one you know with an amp to do this with you.  have them start say on 40 meters at 100 watts. listen to the loudness and look at your recieve s meter.  now have him drop the power to 10 watts, and listen and look at the meter.

now go back to 100 watts and look and listen again. now have him kick on his amp to 400 watts, and listen and read the meter, then have him go to 500 watts ( the max possible on a 811 three tuber safely) and listen and look again, then have him go to what ever his max power is up to 1500 watts.


you will find ther is some difference between all of these, but the most change is from 10 watts to 100 watts. so no sense killing the amp for every last ounce of power. peak it for max output then drop the input 3 or 4 watts. the tubes and amps will last for ever and you can not hear the difference on the other end.  try it, you will see.

some where I remember that you must IED at the start and end of ever qso and every 10 minutes if  the qso is longer that 10 minutes.

I don't remeber if this was part 97 and I'm to lazy to look it up or from my days as a professional dispatcher  for mergency services, but if this is the case the legally you should id at each new call you work as a new qso.

that is what I do.  I mostly contest ssb and when I have a run going I will rerpate his call as I type it in, then give the exchange say 59 and east bay, and he says ok then I drop my call,  I don't qrz and the call, because folks waiting know when you drop your call you are ready for a new one.

if you listen for a couple of calls you can see how the operator is running his  pile, and calif is not rare dx, but I would prefer  an id every call to once every 10 minutes.

FOC I think is the first operators club and you have to be "invited " to join. so I don't find it suprising that they have a private contest.

I did a little more than 300 q's , 2 on 10 m, 80 or 90 on 15 and 20 , some on 40 and 80 and even 8 or 9 on 160.

ran  about 15 hours, got a couple new countries on 160 and some new bands on some of the others.

all and all it was fun

reminds me of a an old friend , got his degree in in electrical engeneering and was a real whiz to boot. I could ask him to draw a circuit to do this that or the other thing and he could whip something right up.

 if I went out and got the parts and gave them to him with a so0ldering iron, we could count on 2 things. first if he built it it mwould not work. second we would be making a trip to the hospital to have the wound on his hand from the soldering iron ( or screwdriver or something )fixed by the doctor.
 

he could design anything but could never get the "hang" of tools.

that said, I have 3 amps that run on 220. I had an electrician run  220 to the shack, and then a friend made up a set of 3  identical boxes in a row so I could plug all of them in at the same time. I just never use more than 1 at a time. some wire, a couple of boxes, and 3 of the proper connectors did the trick.

I recently got a collins 75 A4 and put it on the variac starting at about 30 volts and running it up to 60 volts with in a minute or so, and then let it cook for about an hour and then 90 v for a couple of hours and then 110 v for a couple more hours. always keeping it under observation for any smoke or weird noises,

it seemed to do ok.

on amps I will run them in standby for a bit ( 30 minutes, then turn on the high voltage ( go to operate) with no input for a couple of hours to give those tubes with getters a chance to scavenge the tube from contimanants.

is that the same input tuning unit used for the earlier  Clipperton L's for an input circuit for the amp??

I have had heavy stuff like amps destroyed by fed ex, ups, usps and dhl.

I put on big red frafile stickers on all 6 sides, I also write "Heavy package- 100 pound" on the top and sides and "fragile electronics" . some times it helps some times it don't. I usually pack the stuff in its original box if I have it then put that in a larger box with foam "corners" tyo keep them apart and fill all the voids with foam "angel farts" those little packing pieces of expanded foam.

if it will fit into a 5 gallon bucke  I have used those to ship a well padded package in ( hard to squash) and always remove tubes , wrap them in bubble warp and the in a box in another boax filled with more angel farts,  and the transformers may even get tripple boxed.

they can still break them , but now they have to work at it.

good luck

I never run an alc line on any of my amps. I had a bad problem with them causing motorboating ( up and down power cycles due to alc cuts power, the amp lowers power the alc says bring it back up.. ) so I always tune my tunable amps to max output, ( check the peak and the dip) and then back the input dowan 3 or 4 watts, the tubes last for ever, the signal is clean , and they can not tell the diffrence on the other end.

have a friend with an amp contact you on the air and have him go from 20 watts to 100 watts to a thousand watts to legal limit.  I think you will be supprised at the lack of difference in signal strength.

the 600 watt amp is the bang for the buck amp.

solve this proble one of 2 easy ways, take the amop apart and use the pieces to build youself a decent amp with good design, or sell it on ebay and buy an 811 from ameritron.

I can buy cbamps all day for $280 for a 500 watt RM from several on line "cb" shops , sold for export only. that doesn't make it legal.


I don't care if you operate out of band or not, I am a ham, not a cop. you answer to the FCC for how you run your station, not me.

bottom line is you have some good advice here, what you do with it is up to you.

73 and gud dx

if I am buying new, and they come as a matched set, I will do it that way, but I have a big box with a dozen 811, and another dozen 572's and some 6146's and some 12by7s and 6mj6s, 6js6c' and 6lq6s and so on. If I have a tube go bad and I have one in the box, I swap out the bad one..

funny thing is at the moment, my only tube am runs 3cx807's and at $550 a tube I don't have any spares for that one..

so yes it is good if you can, but cheap is cool too.

I have had a bunch of amps and for that money I would reccommend an ameritron als 600. the price is right and I think about 600 watts.

the reason I suggest this one is to change bands you just turn the band switch on the amp.  no tune up. no peaking the load and dipping the plate. I have had a ton of amps over the years , sbe's and alpha 76a, and an amp supply 1000NT and several als 500's and 811's and 811h's and so on.

right now for HF I only have 3 amps .the Orion runs  an alpha 87a ( legal limit $6000 or so). The 746 pro has an Ic 2-KL ( 800 watts , autotune with Icom radios, about 1500 bucks) , andthe ts 2000 has an ALS 600. this is the one that comes with the 50 volt supply. ($1200 new and 600 watts or so).  all 3 are autotune.

the reason I say the als 600 is for the money it is the best compromise.  if you do any dxing it is instant on and no 3 minute wait, ( important on fresh DX) and if you contest, you can search and pounce up and down the band with no tune up. and changing bands is only one switch. a good compromise, easy to use and holds resale value.

hope this helps some

and remember once you get it working , let it cook in operate with no input for a couple of hours to let the getter in the tubes to do their job. also don't be afraid to drop in the spare tubes  every 6 months or so  to have them evacuate the gasses buy running in operate with no input. the getter removes any off gassing in the tube. and blow out the deck with air now and then to keep the fins cooling in the tubes..

one of the more common problems with the 811 amps is the high voltage power supply.  they run 4 cap and 4 resistors in the supply. the output voltage is 1600 volts and they use four 400 volt caps.

so what happens is one of the resistors across the caps get hotter than the others and flows a little more current causing one cap to aec, and eventually fail. 4 caps and 4 resistors from ameritron is about 40 bucks if I remember correctly..


 so even putting in 572's is with out gain.  a set of 3 tubes for an 811 is 60 bucks and the prce of one 572 is 60 bucks so you can retube 3 times with 811's for the price of 1 set of 572s', and you still don't get anything extra, except for the cost of the tube.

 I have owned 4 or 5 811 and 811 h's over the years and never had a tube go bad. I just tune for max output, then back down the input 2 or 3 watts. the tubes last for ever if you don't try for every last erg of power.

if you want to run legal limit, buy an alpha.