Nowadays the AC mains network is heavily polluted by various domestic appliances, industrial electrical consumers etc. This can lead to buzzy toroidal transformers (especially the power ones). Proposed DC trap (blocker, filter) will remove or at least lower the buzzing.
Schematic is similar to this one used in well known Vladimir Shushurin’s Lamm-1 amplifier. An article with in-dept explanation of how DC blockers work can be found on Rod Elliot’s site (https://sound-au.com/articles/xfmr-dc.htm).
Here is offered a fully assembled device capable to handle VERY HIGH CURRENTS (up to 30 Amperes!!!).
Because of such high currents using a standard PCBs is not possible. Instead of that a 2mm. thick pure copper bussbars are used to connect the filter’s parts.
In order to carry such high loads the part’s values are upraised accordingly:
– FOUR MASSIVE 47 000 uF High-Quality KEMET capacitors
– 6 pcs. 50 Amperes rated High Quality discrete diodes
– one 25W power resistor
– 2 mm. thick pure copper bussbars used for connection of the filter’s part.
All parts used are freshly obtained from reliable sources (Mouser, Farnell, Digi-Key etc.).
The filter is fully symmetrical so the INPUT/OUTPUT terminals are not directional – it is only required that the Blocker is connected in series with the primary winding of your huge toroidal transformer.
What the buyer will receive:
The package will contain 1 pcs. ASSEMBLED and tested DC trap/blocker/filter for toroidal transformers (toroids).
The unit will be shipped with Priority AirMail Registered (or equivalent courier service where applicable). The tracking number will be sent to the customer after shipment.