I am designing a few PCBs for tube preamps and would like to clarify some doubts regarding grounding and particularly the use of ground planes.
Other commercial and diy products I have seen use various solutions : star grounding, solid ground planes and even hatched ground planes.
I am keen to use a solid ground plane because it simplifies routing, but I have read that solid ground planes can be problematic for tube circuits, because of the high impedances at which tubes operate.
I am not sure this should be taken as a general rule of thumb since I am seeing many commercial products using a solid ground plane approach I guess it can be done with the right measures ?
Are there any specific considerations to keep in mind, for example isolation spacing between ground plane and signal traces, or sectioning the ground plane at specific points ?
I have designed the power supply section on a separate board, it's meant to be kind of an universal board that can power various tube circuits. It features HT output with simple crc filtering, unregulated DC for filaments and a section based on LM317 with a voltage doubler/tripler to get 48V for phantom power and a 12V/24V for relays and leds.
All the power supplies based on LM317 I have seen use a solid ground plane, whereas most tube power supply sections I found are without a ground plane, just using a star grounding approach.
Are there any reasons to avoid a ground plane in a tube power supply section ?
Other commercial and diy products I have seen use various solutions : star grounding, solid ground planes and even hatched ground planes.
I am keen to use a solid ground plane because it simplifies routing, but I have read that solid ground planes can be problematic for tube circuits, because of the high impedances at which tubes operate.
I am not sure this should be taken as a general rule of thumb since I am seeing many commercial products using a solid ground plane approach I guess it can be done with the right measures ?
Are there any specific considerations to keep in mind, for example isolation spacing between ground plane and signal traces, or sectioning the ground plane at specific points ?
I have designed the power supply section on a separate board, it's meant to be kind of an universal board that can power various tube circuits. It features HT output with simple crc filtering, unregulated DC for filaments and a section based on LM317 with a voltage doubler/tripler to get 48V for phantom power and a 12V/24V for relays and leds.
All the power supplies based on LM317 I have seen use a solid ground plane, whereas most tube power supply sections I found are without a ground plane, just using a star grounding approach.
Are there any reasons to avoid a ground plane in a tube power supply section ?