Agreed. If you can't drive it with less than 300 watts you'll need to consider an amp with a tube like a 3CX3000A7. That should hold up to this kind of abuse.
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Heathkit SB200 tubes getting red
- Thread starter Jimbo165
- Start date
Agreed. If you can't drive it with less than 300 watts you'll need to consider an amp with a tube like a 3CX3000A7. That should hold up to this kind of abuse.
Originally Posted by Jimbo165
I do not think this is my kind of amp it just not put out enough watts for what you have to do get out any power. I will keep it a little longer but first chance I get to get my money back its gone.:bdh:
Your right Jimbo....Not to be rude...However anyone that drives a 600w amplifier with 300w, should not even have one...
Nobody but another LID would give you $10.00 for any amplifier you've abused in that respect....
Remember everyone this is the same "OP" who said he was getting a 1000w out of a pair of 811's
Sorry but that is the truth!
70-80W PEP is optimal drive for that amp. 200-300W PEP input is asking for trouble.
I ran 15W PEP into my SB200 when I had it (Wavrider has it now) and it put out 200-210W into my Bird meter. Ran great. No need to kill it with all that input.
~Cheers~
That old SB 200 is still rockin, Works great with the TS-820 in front of it.
Originally Posted by Jimbo165
Remember everyone this is the same "OP" who said he was getting a 1000w out of a pair of 811's
Sorry but that is the truth!
:headbang 
Still trying to figure out how you can "turn it up and down a few times". There is no variable voltage or drive level on that amp. Maybe tune/detune or load it perhaps but that is it.
Also if you REALLY believe that 300 watts drive is what the amp likes best (what happened to the ridiculous 200 watt level) then you are either a complete idiot or a troll. Sorry but those are the only two people that would post such a thing. Some of us here know those amps and would agree with what I said.
Well lets just remember that 2 572B's will produce about 600 watts tops in the safe zone with 100 watts of drives. 4 you give you 1200 watts out with 100 watt drive. In thero...unless you hammer them to death.
Now, 572B's give you 160 watts dissipation per tube, so with 4 you have 640 watts dissipation total. The SB200 only has 2 tubes. So do the math...
I get SB200's, SB220's, and drakes in the shop all the time. The biggest killer in these amps are the power supply. They are just too small and will not supply enough current to run them.
I really hate to say this but I will. A lot of folks think that a 100 watt device, say like a 2SC2879 will produce 200 to 300 watts. Because they see it on the meter. This is bull. And the same goes with tubes. What folks fail to see in these claims is most "CB" style watt meters do not know the difference from the on frequency power dissipation and harmonics. The meter simply adds them all together.
If you take a radio with a 12 watt final and tune it to get 25 to 30 watts out of it it has to be louder right? NO, it is distortion and the meter combines it all together.
Ok, I will shut up on this now.
Now, 572B's give you 160 watts dissipation per tube, so with 4 you have 640 watts dissipation total. The SB200 only has 2 tubes. So do the math...
I get SB200's, SB220's, and drakes in the shop all the time. The biggest killer in these amps are the power supply. They are just too small and will not supply enough current to run them.
I really hate to say this but I will. A lot of folks think that a 100 watt device, say like a 2SC2879 will produce 200 to 300 watts. Because they see it on the meter. This is bull. And the same goes with tubes. What folks fail to see in these claims is most "CB" style watt meters do not know the difference from the on frequency power dissipation and harmonics. The meter simply adds them all together.
If you take a radio with a 12 watt final and tune it to get 25 to 30 watts out of it it has to be louder right? NO, it is distortion and the meter combines it all together.
Ok, I will shut up on this now.
SB200 tubes getting red
First I would like to thank all the people that have helped me as I try to work on me or my brothers equipment I am in a constant learning stage. Second Captain Kilowatt you can stick the idiot or troll comment where you like it the best and I can send a picture where I believe they should go if you want I may not have been a electronic genius like you in my lifetime but for 30yrs a Tool & Die Maker card holder and 8yrs as a Maintenance Tech 3 for Chrysler. I may have been unclear about turning amp up or down I meant I flipped it from one side to another while checking it and it started working sorry for me adding to your confusion. Mr FX Dosey or Bird does not matter to me what I do is get it on air to people I talk to everyday and they tell me signal strength or modulation results works for me regardless what meter reading is . Radio Tech I realize I am not even close to knowing what a lot of you do but I
am trying on plate dissipation two572b would be 320 w ok 10 6LQ6 tubes in a 10 tube Phantom would have 300w dissipation the Phantom will do 1000w pep or 500 avg why wouldn't two 572b which have 320w put out the same or more if you drive it and those 572B tubes will take drive ? Now if you run a JB12 or 150 into Phantom it will put out for sure just ask anyone that has run this type of combo I do not have a bird to prove this but only results from signals put out to friends over 30 miles away from me. Shockwave and wavrider Thanks for your comments. I am trying fellows just got back into radio 3yrs ago Hope all had a Great 4th of July Jimbo165
First I would like to thank all the people that have helped me as I try to work on me or my brothers equipment I am in a constant learning stage. Second Captain Kilowatt you can stick the idiot or troll comment where you like it the best and I can send a picture where I believe they should go if you want I may not have been a electronic genius like you in my lifetime but for 30yrs a Tool & Die Maker card holder and 8yrs as a Maintenance Tech 3 for Chrysler. I may have been unclear about turning amp up or down I meant I flipped it from one side to another while checking it and it started working sorry for me adding to your confusion. Mr FX Dosey or Bird does not matter to me what I do is get it on air to people I talk to everyday and they tell me signal strength or modulation results works for me regardless what meter reading is . Radio Tech I realize I am not even close to knowing what a lot of you do but I
am trying on plate dissipation two572b would be 320 w ok 10 6LQ6 tubes in a 10 tube Phantom would have 300w dissipation the Phantom will do 1000w pep or 500 avg why wouldn't two 572b which have 320w put out the same or more if you drive it and those 572B tubes will take drive ? Now if you run a JB12 or 150 into Phantom it will put out for sure just ask anyone that has run this type of combo I do not have a bird to prove this but only results from signals put out to friends over 30 miles away from me. Shockwave and wavrider Thanks for your comments. I am trying fellows just got back into radio 3yrs ago Hope all had a Great 4th of July Jimbo165
Some of us know tubes and their limits. You were given some info on how badly tbose tubes were being over driven. You chose to ignore that and make outrageous claims about how the pair of 572B's liked 300 watts of drive hence what I said. People who claim no knowledge of how to operate something and then ignore good advice from knowledgeable people and continue to make absurd claims generally fall into one of two categories. I mentioned them both above. Like it or not it is what it is. Also be careful of who you tell to stick something somewhere. You could find yourself stuck somewhere else.
It doesn't however a pair of 572B's does not require 100 watts of drive delivered to the cathodes for 600 watts out. Most amps of this type have swamping on the inputs which limits actual drive to the tubes to 50-60 watts. Amps with four 572B's fo not thus allowing the full 100 watts of drive to the tubes.The actual gain is the same. The actual drive level is doubled.
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A good rule of thumb to follow for proper operation of a tube amp operated in a linear class of operation is that the available power output is two times the plate dissipation. For a pair of 572B's that is 160 watts times two for 320 watts plate dissipation so they should be good for 640 watts. What do you know. Most amps using that tube compliment are speced for 600 watts out. The Ameritron AL-572 uses four of them and is speced for 1300 watts output. A pair of 3-500Z's have 1000 watts plate dissipation and will make a hair over two thousand watts when pressed to the limits. I won't even get into what most CBers claim from an amp because I am talking about maintaining a linear class of operation and operating the amp within design limits of the tubes. I can make a 6KD6 produce 200 watts but it won't be clean nor will it last long however it will do it. BTW the plate and filament run the same colour just before the tube goes supernova.
SB200 tubes turning red
Why does a SB200 with two 572B's with 320w dissipation make only 640w output when a D&A Phantom with 10 6LQ6 tubes equaling 300w dissipation make 1000w output with a 4w drive. The Phantom has less total dissipation. Tubes in a SB200 will take a 300w drive because my brother has been doing it to his SB200 for over a year now with same tubes no major problems and he is getting a lot of contacts that a 640w amp would not be able to get he uses his to talk skip on channel 17 and 28. He knows the tubes are not going to last but that is why he chose the SB200 two tubes are cheaper than 10 like in my Phantom. There are a lot of people out there pushing their amplifiers well past design limits sure they will break but they will tell you the reward is worth the pain. I do not plan to drive my SB200 like that I mainly bought it to use on 38LSB but still wanted maximum output but have plug in the wall pill amps that can do almost the 640w output of Heathkit so may sell the SB200 a lot of people in my area that have heard it on air and want it already. I hope I can still count on all the great help this forum has given me . Thanks Jimbo165
Why does a SB200 with two 572B's with 320w dissipation make only 640w output when a D&A Phantom with 10 6LQ6 tubes equaling 300w dissipation make 1000w output with a 4w drive. The Phantom has less total dissipation. Tubes in a SB200 will take a 300w drive because my brother has been doing it to his SB200 for over a year now with same tubes no major problems and he is getting a lot of contacts that a 640w amp would not be able to get he uses his to talk skip on channel 17 and 28. He knows the tubes are not going to last but that is why he chose the SB200 two tubes are cheaper than 10 like in my Phantom. There are a lot of people out there pushing their amplifiers well past design limits sure they will break but they will tell you the reward is worth the pain. I do not plan to drive my SB200 like that I mainly bought it to use on 38LSB but still wanted maximum output but have plug in the wall pill amps that can do almost the 640w output of Heathkit so may sell the SB200 a lot of people in my area that have heard it on air and want it already. I hope I can still count on all the great help this forum has given me . Thanks Jimbo165
Ok Jimbo, first off this is not meant to be derogatory but you obviously do not understand a few things. First, an amp that makes 1000 watts will not make generally contacts that an amp making 640 watts cannot. There is less than one half of an S- unit difference between 640 watts and1000 watts. That is a simple law of physics that cannot be broken. I have switched power by 10 times and hardly made a difference. There are times when running on the ragged edge where it will make the difference between making contact or not but those times are quite rare. The other thing is tube life. I already mentioned about what CBers do to amps in the quest for more power and you pretty much confirmed that by saying about the shortened tube life. The other BIG thing not yet mentioned about the Heath amps is that the power supply is not capable of providing enough current and voltage to run those tubes much beyond 600-700 watts. Heath amps have never been known for having beefy power supplies even in the 3-500Z amps.572B's really like to see about 2400 volts on them and IIRC the SB200 runs less than 2000 and has small wire on the transformer which limits current to a point in which you start to see excessive voltage drop when you try and push the crap out of the amp.
As for the D and A or whatever making more power with less dissipation, well I would like to see it at 1000 watts versus the Heath at 640 watts on a spectrum analyzer and oscilloscope. One will be vastly cleaner than the other whether someone on the receiving end realizes it or not. Most people cannot tell when something sounds good or when it sounds GOOD. Most equate good to being loud and if it splatters all 40 channels then it must be putting out a lot of power and working good. I have even heard people telling loud distorted signals that they sound GREAT! Signal strength isn't everything.
As for the D and A or whatever making more power with less dissipation, well I would like to see it at 1000 watts versus the Heath at 640 watts on a spectrum analyzer and oscilloscope. One will be vastly cleaner than the other whether someone on the receiving end realizes it or not. Most people cannot tell when something sounds good or when it sounds GOOD. Most equate good to being loud and if it splatters all 40 channels then it must be putting out a lot of power and working good. I have even heard people telling loud distorted signals that they sound GREAT! Signal strength isn't everything.
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