madbeanpedals::forum

Projects => Tech Help - Projects Page => Topic started by: mark123 on December 29, 2017, 07:54:58 PM

Title: Successful Wumpus build (unboxed) with a question
Post by: mark123 on December 29, 2017, 07:54:58 PM
I didn't have a 15nF cap so I stuck in a 18nF to get it tested.  It actually works.  I've got some 15nF caps coming in so I'll swap it out later.

In its current configuration it seems that I've got to max out all the trimpots (except BRIGHT is at the other extreme at zero) to get it to work properly.  Is this normal? No adjustment seems to be available.
Title: Re: Successful Wumpus build (unboxed) with a question
Post by: mark123 on January 05, 2018, 10:21:34 AM
The Wumpus has died. I was playing it and it just pooped out. Either the signal trace that lifted off the board broke free or I blew out one of the LEDs.

RIP
Title: Re: Successful Wumpus build (unboxed) with a question
Post by: WormBoy on January 06, 2018, 03:35:54 AM
That sucks ... when you mention potentially blowing an LED, In this circuit, the LEDs have no limiting resistors whatsoever. The tapanatorator has a similar BJT/LED setup but does include a limiting resistor (330 Ohm, running of 5V). Perhaps the antenna driver of the Wumpus is never able to turn the transistor fully on, or my knowledge is insufficient, but if you indeed have a blown LED I would like to know. I am in the process of building one myself, still waiting for some parts.
Title: Re: Successful Wumpus build (unboxed) with a question
Post by: mark123 on January 06, 2018, 08:36:05 AM
I'm almost 80% sure is a blown LED. I'll have to tear it apart when I get a few moments. Maybe next week.

The biggest downfall of the design is you have to get actual flesh near the sensor. A shoe keeps your foot too far away for it to work. And you know how I feel about barefoot pedal demos. Bleh! But it works and is fun.
Title: Re: Successful Wumpus build (unboxed) with a question
Post by: WormBoy on January 07, 2018, 10:05:58 AM
If it only works with bare feet or socks that would be a pity ... At home, fine, but on-stage I am not going to remove my shoes to go sock-hoppin' wah-in' ;D. As the Wumpus closely resembles the wah probe, I have hopes that it can work with shoes, if needed with some tweaking (the probe seems to work ok with shoes).
Title: Re: Successful Wumpus build (unboxed) with a question
Post by: EBK on January 07, 2018, 10:43:02 AM
You just need different shoes, maybe.  There are plenty of vids of folks with shoes using zvex probes.
Example:
Title: Re: Successful Wumpus build (unboxed) with a question
Post by: WormBoy on January 08, 2018, 02:37:30 AM
You just need different shoes, maybe.  There are plenty of vids of folks with shoes using zvex probes.
Yes, but the Wumpus is not identical to the Zvex probe. There are a few differences in the antenna circuit part, but I have no clue how they affect sensitivity. Plus, a lot will probably depend on the antenna (size, shape, material, placement). And, donít forget the choice of LED and LDR ...