Soldering printed circuits using radiant heat

An electronic device comprising:

• a first printed circuit comprising a two-dimensional pattern of contacts on a first surface, wherein the two-dimensional pattern of contacts comprises a contact density between 0.5 contacts/mm2 and 4.0 contacts/mm2;
• a second printed circuit, the second printed circuit comprising a multilayer printed circuit comprising a first layer facing the first surface of the first printed circuit and a second layer opposite the first printed circuit, the first layer comprising a first blind via, the second layer comprising a second blind via, the second blind via aligned with the first blind via;
• and
• a solder joint formed between a first contact of the two-dimensional pattern of contacts of the first printed circuit and the first blind via of the multilayer printed circuit.