After reviewing /u/peaceduk 's posting history, it's hard to come to any conclusion other than him (I assume) being an intentional, blatant spammer.

So I sent /u/peaceduk the following message via PM:

"If you want to continue posting in /r/RFElectronics, your posts need to be relevant to the subreddit's topic and not be massively cross-posted spam. Since your posting behavior shows your true intentions, I don't feel the need to warn you that what you're doing is wrong. You understand that quite well.

Don't spam /r/RFElectronics with Bitcoin-related content (or any other non-RFElectronics content) again, or you'll get a permaban from this subreddit."

Then I hit the "spam" button on his most recent posting here. (Which hides the post, and notifies the Reddit Admins that it was considered spam.)

Any questions/concerns, please let me know. (A comment here or a mod-mail are both fine.)