Supro 1688rt icircuit board full#

Not quite full Class A for a 6L6GC, but overheated for a 5881. *For 30W 6L6GC, you'd use 389/(30/389) = 5k plate to plateДЄnd if the shared Rk measures 200R exactly, the shared current is 29.5/200 = 0.1475A, which is 74mA per tube - less 5mA g2 current = 69mA. For this type of Class A operation, with plate voltage of 389VDC, and assuming you have (say) 20W 5881s*, you want to be running a load resistance of 7k5 plate-to-plate (or slightly higher). What sort of 6L6/5881s are you running? (Some of them are only rated for 19 or 20 Watts)Д¬heck that you have the correct load resistance for the tubes. Theres no channel switching - although it is possible to swap between the two input jacks on both amps using a standard A/B footswitch. You also need to know exactly what the cathode resistor's resistance is, before you can get a reliable calculation of cathode current (which will be shared by 2 tubes in this case)ДЄ 5881 screen runs at about 5mA when its set up at about 400V on the plate/screen (so this should be subtracted from the cathode current to get the plate current for each tube). The preamp valves are mounted on one board horizontally, pointing forward, while the phase splitter and power valves sit on the other PCB, that hangs vertically on the underside of the chassis. Building a new small pedal board for my Supro Black Magick head.Pedals used :EVH ChorusSupro BoostMaxon OD-808 OverdriveProCo RatBiyang Time MachineGuitar Us. Yes it seems like a bad tube at this point.ДЇWIW 389V on the Plate and 29.5V on the cathode = 359.5 plate-to-cathode, which is what you use to assess plate dissipation. Oops - forgot this thread was about a t-bolt LoL.

Suggestions please, I'm really torn here and I'm not really sure how much difference it will make. The price is not meaningfully different and they both will require me to make an adapter plate to fit the chassis, so that doesn't help me decide. Part of me wants to use a 4k transformer to get closer to the supro, but I also kind of like the idea of letting it be a dirtier amp and I certainly won't miss 5 or so watts of output in a 40 watt amp. The best I am able to interpret this is that with my voltage and the 5K I will get less headroom, more distortion, and slightly less output wattage as compared to the 4k or the original thunderbolt with the higher voltage and 5K. If I substitute a 4K primary in with my 380v the lines moves up above the knee and looks more like the Supro. With my estimated B+ of 380v and a 5k primary I get a line right at the knee of the graph, but when I plot the original thunderbolt at 425v and 5K I get a line a good bit above the knee. This afternoon I plotted some load lines for my estimated voltages using the interactive data sheets at BM amps, and it looks like a 4K primary might actually get the tubes to preform more like the original thunderbolt. Originally marketed as a bass amplifier, the Supro 1688TN is a two channel 2x12 guitar amp from the early 1960s with 35W of Class-A power and built-in tremolo. Originally I was planning to use the 40W Supro reproduction that classic tone sells with a 5K primary. Speaking of the OT, I am about ready to order it and I can't quite decide what to get.

Supro 1688rt icircuit board