Happy Black Fuzz Friday, everyone! Be sure to check out the store for a bunch of new boards and a 15% off Black Friday sale. Use coupon code "blackfuzzfriday" at checkout.
Here's a cool silicon Buzzaround variant I found browsing DIYSB. Any low hFE transistors should work ok. 2N2222A, 2N2369, MPSA42, etc. Should fit nicely in a 1590B.