Anyone know of any DIY Delay pedals with a hold feature like the Jam Pedals Delay Llama?
http://www.musicradar.com/gear/guitars/fx/delay/delay-llama-plus-546797
The hold feature on the Llama is often called slam, or oscillation, or any number of things. Essentially, you're forcing the feedback pot into max repeats where it begins to oscillate. It's common, and easily done in any PT2399 or BBD type delay. Take a look at the Echobase for a project with it built right in. I think the ZeroPoint will have it as well.
Jacob
I just built this into my Neptune, too. All you need to do is wire lugs 2 and 3 of your feedback pot together through a momentary switch, and you're set.