Victor Chew

Operating Max for the IXYS I believe is 150C. It gets quite hot and humid around here in the hot months. I believe Kevin said if you can leave your hands on the heatsinks for more than 5 seconds, its not too hot. I can do that, but I might have thicker skin. ! I would also like to build the megatron when the boards become available.

Its 30C to 35C room temp between June to October. The amp runs at 80C plus and the power supply heatsinks are just as hot. You want plenty of ventilation for the onbaord version to reduce the high temperature "attack" on the parts, especially on hot days.

Yes, I was referring to the output tube filament terminals. Tks for the reply Spritzer.

Nice. But "Pro" not required since you have only have 5 pins.

Spritzer, would it be possible to have a hole near each of the internal heater filament terminators for the wires to reach them? This is to keep the wires from spanning across much of the board to prevent humming. Perhaps my unwarranted fear of humming. Am I correct that each of the 6CA7 will require 1.5A? If so, one transformer with 20va with 1.587A x 2 can feed 2 large tubes. Am I also correct that each of the small tubes will require 500mA? If so, one transformer with 14va with 555mA x 4 can feed all the 4 small tubes. I stand correct in respect of the above.

Nice work and pictures Enrique. The 580v bias measures ok as well?

Nice work pagan.

This would have to be a 2 box build. What would be the costs of building this amp excluding the cost of volume pot?

Spritzer , thanks for the heads up on the heat issue. How many transformers are we looking at for this "monster"? I believe 1 for the PSU; 1 shared for the input tubes ( L and R) and 1 for left output tubes and 1 for right output tubes? Total 4 transformers?

Would the Megatron be too hot to operate without heat problems in the equitorial climate? Temperature ranges from 30C to 34C most of the year but a fews digits lower during the monsoon season, which is now.

Megatron! I can feel the heat. Enrique will be thrilled. Spritzer will you be using the rk27?

Congratulations jwzhan! Everyone wants happiness. No one wants pain. But you can't have a raimbow without a little rain..

Thanks alot John. I will have to go get the turner 600. Yes, Singapore is a humid place. I do keep the equipment covered after use but little dust does not mean no dust.

Recently, been getting more and more irritating static noise from my volume pot. It's definitely coming from the dact. Infact, from day one the static noise was already there but, only in one channel and I put up with it. Recently, its been getting worse and its now in both the channels. Anyone has the same problem?

Lilknight is where many of us got the board from. PM him to see if he has got any left.

Which is real and which is fake? Or are boith real?

Nice work. Wiring has been discussed over hear quite a few times. 1. In anycase, ground the XLR to chasis. They should not be grounded together with the boards which should have a different ground point. I used different grounding points for left and right channel. 2. If I remember correctly, the boards can share a common ground as the iec. ie. Star ground 3. The volume point also ground to chasis. I also had different ground points for both the channels. 4. Twist the wire together to reduce radio frequency interferences. I believe there is no absolute correct grounding. The above is what I used and the amp is dead silent. The fact that it is blowing higher rated fuses means it is pulling more current. Are you using slow blow? I had the same problem as you and the slow blow solved the problem. However, I am not using slow blow as I found the normal 3A sound "better" to my ears. As for the buzzing of your iec, check that its not coming from the sumR?

Nice and clean work. What transformer did you change it to? SumR as well?

Congrats John. Any pictures of your mod to show us?

Amb only sell to builders of their amp. I had to do the matching myself and was pretty lucky. Followed : http://www.diamondstar.de/transistor_matching_jfet.html

Livewire, just for knowledge what were the changes you had to make to the circuit to accomodate the use of the 10m90s in place of the 1968? I beleive that in the KGSShv the were some difference for both the resistor and diode values.

Hey, no worries JoaMat. I think Tran still has exams and what not to attend to. His replies may not be immediate, but he eventually does attend to them. He is a reliable chap.

I got mine from Lil knight. You might want to PM him and check if he's got any left.

True love is forever, in heart and in soul. Enjoy your trip our friend. Jwzhan, your perseverance has paid off although earlier on you had doubts as to whether you could get this PSU to function. Keep us posted of the balance of your journey.

Any suggestions on how to check if the LT1021 is real and if it is, whether it is working to spec.before plugging it and letting charred parts tell us that it is bad?