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 device capable to handle VERY HIGH CURRENTS (up to 30 Amperes!!!) assembled in a steel case – black powder coated.
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 with 4 x 47 000 uF capacitors, 25W power resistor etc. For further description of the High-Power DC Blocker see here: High-Power DC Blocker Unit
Note that the Blocker undergone a redesign and now it has 6 discrete diodes which allows it to block DC shifts up to 2V!
The capacitor block is firmly connected to the bottom of the case with brackets and rubber sheet.
The input and output cables must be connected together via Barrier Terminal Block or Screw Terminal (see attached pictures). The Barrier Terminal Block is useful when cable wires end with ring terminals or are “eared” (in case of solid core wires). The Screw Terminal is preferred when you want to easily plug the stripped wire’s ends into and tighten with screws.
The green-yellow wire attached to the steel case must be tied to the “Ground”/”Protective Earth” wire in order to comply with all safety requirements.
There are 4 rubber feet on the bottom of the case which ensure that case will not scratch the underlying surface.
Unit’s weight: 2.350 kg.
What the buyer will receive:
The package will contain 1 pcs. FULLY ASSEMBLED and tested HIGH-POWER DC trap/blocker/filter for toroidal transformers (toroids) in steel case.
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.