Hello forum,
got all parts together for building a p2p wired TSEII for 300b tubes.
All in all I´m actually planning the wiring to get into the chassis bulding process right afterwards.
Do you think the following grounding scheme is suffcient or will it cause problems?
Many thanks
Rents
got all parts together for building a p2p wired TSEII for 300b tubes.
All in all I´m actually planning the wiring to get into the chassis bulding process right afterwards.
Do you think the following grounding scheme is suffcient or will it cause problems?
Many thanks
Rents
You could do it, but isn't the objective to buy George's boards and support his hobby R&D? It seems cheeky at best to ask for advice on how to bypass that part of the whole Tubelab thing.
I have no problems with people building my designs PTP or any other way. I have assisted with these designs when I can.
There was a guy a few years ago who built a PTP SSE which is easier, and there have been quite a few of. He argued about many things myself and others here told him to do, then complained when nobody here could remotely diagnose his hum problem without pictures. Then he ranted on for a while about how the design sucked, then just disappeared.
The deal with getting ground right is to recognize the individual current loops in a design, separate them and bring them together at just one point.
In the case of the TSE there is a high current loop for the filament current of the output tubes. It is also the return circuit for the plate current. The cold end of each tube heater should be returned to the negative end of the filter cap in the heater supply (C1, C12, and C13, which could all be one big cap in a PTP build). All grounds for the heater supply the transformer CT in a 2.5 V build, and the regulator should go to the negative end of C1. This keeps the low voltage AC and DC currents all in their own sub circuit.
The main B+ cap (C5) should be located reasonably close to these caps with a fat wire joining the two negative terminals (C1 and C5). The actual star ground point is the negative end of C5. All power supply related grounds come to the negative end of C5, including positive ends of the bias supply caps, the transformer HV CT, and any added extra capacitor.
The grounds for the cathode and grid resistors on the 5842, and any bypass caps in the B+ for the driver should also go to the negative end of C5.
There was a guy a few years ago who built a PTP SSE which is easier, and there have been quite a few of. He argued about many things myself and others here told him to do, then complained when nobody here could remotely diagnose his hum problem without pictures. Then he ranted on for a while about how the design sucked, then just disappeared.
The deal with getting ground right is to recognize the individual current loops in a design, separate them and bring them together at just one point.
In the case of the TSE there is a high current loop for the filament current of the output tubes. It is also the return circuit for the plate current. The cold end of each tube heater should be returned to the negative end of the filter cap in the heater supply (C1, C12, and C13, which could all be one big cap in a PTP build). All grounds for the heater supply the transformer CT in a 2.5 V build, and the regulator should go to the negative end of C1. This keeps the low voltage AC and DC currents all in their own sub circuit.
The main B+ cap (C5) should be located reasonably close to these caps with a fat wire joining the two negative terminals (C1 and C5). The actual star ground point is the negative end of C5. All power supply related grounds come to the negative end of C5, including positive ends of the bias supply caps, the transformer HV CT, and any added extra capacitor.
The grounds for the cathode and grid resistors on the 5842, and any bypass caps in the B+ for the driver should also go to the negative end of C5.