The DIY Trezor Chronicles: A Journey in Electronics

The transparent and openly accessible character of numerous hardware cryptocurrency wallets facilitates a unique opportunity for individuals to embark on the journey of crafting a do-it-yourself (DIY) wallet, resembling the esteemed Trezor, from the ground up. However, this endeavor demands a specific set of skills and expertise.

In the year 2018, Florin Cocos, a proficient electronics design manager hailing from Romania, embarked on an ambitious project to construct his very own DIY Trezor, harnessing the power of the wallet's open-source code, even in the absence of access to an authentic Trezor device.

Venturing into the realm of educational content creation, Cocos showcased the meticulous process of giving birth to the DIY Trezor Model One on his prominent YouTube channel, Voltlog. In this creative endeavor, electronic components were procured from reputable suppliers such as Farnell, where a Farnell microcontroller and a bespoke printed circuit board (PCB) were meticulously chosen. This PCB, a critical component, was carefully sourced from a renowned production facility in China, extracted from a Gerber file made available on Trezor’s GitHub repository.

Elaborating on the sourcing of components, Cocos shared his wisdom on the Voltlog blog, stating, "The necessary components can be acquired from well-established suppliers like Farnell, DigiKey, RS, Newark, TME. The choice ultimately hinges on your geographical location; obtaining them from a local supplier might be advantageous. Additionally, the OLED screen, a pivotal component, can be readily sourced from online platforms like AliExpress or eBay," further enhancing accessibility.

The printed circuit boards (PCBs) utilized by Voltlog in the construction of a DIY Trezor wallet. Source: YouTube  

Half a decade since the release of his enlightening DIY Trezor video, Cocos remains deeply passionate about his brainchild, the DIY crypto contraption. He avowed, "I have not only utilized this self-crafted device extensively but also harbor unwavering trust in its capabilities, always favoring it over a wallet acquired from mainstream marketplaces." These sentiments were shared during a captivating interview held on the 19th of September.

Setting up the DIY Trezor took approximately 10 hours for Voltlog

The meticulous setup for the DIY Trezor undertaken by Voltlog demanded approximately 10 hours of dedicated effort. Yet, it's noteworthy that the motivation behind Cocos' DIY wallet creation transcended mere market availability. The engineer's main drive was rooted in a profound desire to disseminate knowledge and awareness regarding the burgeoning realm of open-source projects.

"Open-source designs are gaining tremendous traction and, in my humble opinion, represent the future of innovation," Cocos asserted, underscoring the pivotal role of open-source concepts.

You have full control over the security aspects, and it’s always fun to build something yourself. For me personally, the idea of making something useful, myself, contributes more than anything else to the decision to start such a project.

Reflecting on the comprehensive journey of building and implementing firmware on the DIY Trezor wallet, Cocos shared that it was a laborious yet fulfilling process, consuming a considerable chunk of his time, approximately 10 hours. This duration excludes the time invested in patiently waiting for the arrival of the vital PCBs and other meticulously ordered components, demonstrating the importance of patience and meticulous planning in such endeavors.

"I'd estimate it took me perhaps two or three hours to meticulously evaluate the entire project, generating the essential Gerber files necessary for submission to a PCB manufacturing service, and meticulously placing orders for all the necessary parts from reputable suppliers such as Mouser or Digikey," Cocos detailed. After the long-awaited arrival of the PCBs, it was another five hours of intense focus and dexterity to meticulously assemble the PCB, load it with the essential firmware, and set it in motion, Cocos added.

Interestingly, the hardware fabrication for the DIY Trezor was perceived as the least formidable aspect of the entire process, a testament to Cocos' expertise and dedication. He emphasized that while this facet posed its challenges, the more intricate aspects involved flashing the firmware and aligning it seamlessly with the application, a task that demanded a more nuanced and meticulous approach.

What level of complexity does the construction of a DIY Trezor present for an average individual?

Delving into the realm of accessibility and demystifying the DIY Trezor creation process for the average user, questions arise regarding its level of complexity. While the time invested might not appear overly extensive, it is imperative to dispel the notion that crafting a DIY Trezor is a simplistic task for the average user, according to Cocos.

From the vantage point of the engineer, the endeavor is "virtually unattainable" for an average user devoid of foundational knowledge in electronics. "On a scale where 10 represents the zenith of difficulty, I would unreservedly rate this endeavor as a solid 10," Cocos affirmed, endeavoring to encapsulate the magnitude of complexity in conceiving a DIY Trezor for an average user.

To simplify the process, Cocos acknowledged the potential to streamline the undertaking, albeit at the expense of confronting significant security risks, particularly those intertwined with supply chain and manufacturing susceptibilities.

"In principle, it's plausible to streamline this process by curating a comprehensive 'makers pack' for the project, encompassing all the requisite manufacturing files in their specific, user-friendly formats. One could then conveniently upload this package to one of the myriad PCB and PCBA prototyping services available online. Yet, at this juncture, while the difficulty level would subside to around 3 on a scale of 1 to 10, one would invariably relinquish a degree of control over the supply chain and manufacturing process, consequently introducing an added layer of security risk," the engineer elucidated, highlighting the delicate balance between simplicity and security.

Cocos passionately advocated that haphazard attempts to forge a DIY Trezor devoid of adequate knowledge could potentially expose individuals to substantial security risks, urging for caution and prudence:

I would not recommend building such a hardware wallet if you are not experienced with electronics and specifically with soldering small surface mount components. If that’s the case, the result is likely just the magic smoke escaping or, at best, a brick that does nothing.

Cocos, who modestly described himself as an occasional cryptocurrency user, boasts a bachelor's degree in electrical engineering and an extensive professional tenure of ten years dedicated to the realm of electrical engineering and electronics design. Additionally, his passion for tinkering with electronics has persisted as a cherished hobby for over 15 years. He firmly believes that one need not attain the level of expertise he possesses to embark on the journey of creating a DIY Trezor. However, a foundational understanding and proficiency in electronics remain prerequisites.

"A mere one or two years of delving into electronics at a moderately brisk pace by an individual with a moderate level of technical acumen should suffice to significantly bolster the likelihood of success," Cocos opined, further emphasizing the accessibility and potential democratization of this fascinating realm of DIY hardware wallets.

As has been previously documented, unfortunate instances have come to light where cryptocurrency enthusiasts have fallen prey to counterfeit hardware wallets due to unwitting purchases from dubious sources, bypassing the official manufacturer or authorized vendors. Consequently, prominent hardware wallet manufacturers such as Ledger and Trezor have been steadfast in urging their discerning customers to exercise caution and procure hardware wallets exclusively from credible, authorized vendors.

Notably, there exist regions where hardware wallets face logistical challenges in terms of shipment due to various geopolitical issues, including sanctions. In light of these circumstances, companies like Trezor have proposed that the open-source nature of their devices could potentially serve as a viable solution. "Trezor is fully open-source; anyone can embark on the journey of creating their own hardware wallet using the comprehensive schematics and bill of materials generously provided on GitHub," a testament to the ethos of openness and accessibility that underscores Trezor's Bitcoin mission.

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