Alright, is the inrush current limiter necessary for the SSE? If so, is this placed on the board? From what I can determine, there are 2 versions of the board, one with a location for the ICL and one without. If not placed on the board how and where is this typically added? Any help with this would be appreciated. Thanks.
First I'd like to point out that I'm no expert, I just got my amp going yesterday. But I'm willing to share what I do know.
I used a CL-140 inrush limiter. I don't think it is required but it's purpose is to protect your components. I think it would be mistake to bypass it.
From what I understand it was not originally in the circuit. I believe that rectifier tubes were being damaged (I think, I must have read that about a year ago so don't quote me on this.) George then made a second version of the board that included the CL-140. This is an improvement. He no longer sells boards without it. I don't want to take my amp apart to check (I've taken it apart many, many times in the last few days!) but I believe the spot for it on the board is TR1
I'm no expert, you might want to do a search of this form for
TR1
CL-140
and inrush limiter
Good luck
I used a CL-140 inrush limiter. I don't think it is required but it's purpose is to protect your components. I think it would be mistake to bypass it.
From what I understand it was not originally in the circuit. I believe that rectifier tubes were being damaged (I think, I must have read that about a year ago so don't quote me on this.) George then made a second version of the board that included the CL-140. This is an improvement. He no longer sells boards without it. I don't want to take my amp apart to check (I've taken it apart many, many times in the last few days!) but I believe the spot for it on the board is TR1
I'm no expert, you might want to do a search of this form for
TR1
CL-140
and inrush limiter
Good luck
The current versions of the SSE have place for a pair of diodes and a CL-140 on the PCB. These were added several years ago in response to a rash of poor quality 5AR4 tubes over a year or so. The CL140 slows the rush of B+ current, while the diodes add additional PIV protection for the tube. All the capacitors in the amp are empty and need to be charged. At the same time the rectifier tube is waking up and not up to full capacity. A tube with an unevenly coated cathode will conduct most of it's current at its warmest point, which is where the coating is the thinnest and most vulnerable....sparks happen.
None of these components are strictly required and may be replaced with a wire jumper if someone desires, but the quality of new production tubes varies with each batch, so they help it live a long and happy life.
It is possible to add an additional limiter to the SSE. It is used to soften the inrush surge of all current into the amplifier on initial turn on. Again this is not required, but may help improve the lifetime of the tubes and capacitors in the amplifier. An SL90 can be added in series with the line voltage. This would have to be wired in series with the wiring from the fuse holder to the power switch or the wiring from the power switch to the power transformer. Usually this would require an additional terminal strip to be mounted somewhere under the chassis.
A tube with say a 2 amp heater will draw as much as 5 amps when first switched on. An SSE will draw about 4 amps in the first few milliseconds after switch on tapering quickly as the tubes warm.
None of these components are strictly required and may be replaced with a wire jumper if someone desires, but the quality of new production tubes varies with each batch, so they help it live a long and happy life.
It is possible to add an additional limiter to the SSE. It is used to soften the inrush surge of all current into the amplifier on initial turn on. Again this is not required, but may help improve the lifetime of the tubes and capacitors in the amplifier. An SL90 can be added in series with the line voltage. This would have to be wired in series with the wiring from the fuse holder to the power switch or the wiring from the power switch to the power transformer. Usually this would require an additional terminal strip to be mounted somewhere under the chassis.
A tube with say a 2 amp heater will draw as much as 5 amps when first switched on. An SSE will draw about 4 amps in the first few milliseconds after switch on tapering quickly as the tubes warm.
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