Spin Semiconductor

i really appreciate you posting all of these thoughts, thank you!!

now i feel a bit silly for always using a 78Lxx regulator just because all the boutique builders do

any luck with this? i wonder how close you can get just by adjusting the clock rate of one of the stock reverbs.

also, worth noting that both eqd and pedalpcb are using the simple clock oscillator circuit from the knowledge base: http://www.spinsemi.com/knowledge_base/xtal.html

interesting! do they use the same larger values for REFP?

speaking of commercial products, i did some poking around and zcat pedals use MLCCs for both MID and REFP: http://www.effectsdatabase.com/model/zcat/polyoctaver

oh i see! tantalum does seem safest, as is used on the dev board. though personally i'm going to try some standard standard ceramics on my next build to find out for sure, like frank suggests also, you can get 1uf C0G caps for the low price of... $15 each :lol: https://www.mouser.com/ProductDetail/K...

oh that's great to know! any excuse to avoid an electrolytic is a nice help.

i doubt the microphonics would matter, since it's unrelated to the signal path and connected to ground. we all use ceramic caps for the DVD+AVD pins and for the crystal, but that doesn't cause any trouble.

good to know, thanks very much!

in the schematic on the fv1 manual, the resistors connected to the S0, S1, S2, and T0 pins are all 20K. i'm curious as to why this value was chosen, and how important it is to use this specific value? i figure 18K or 22K would be fine, but what about values like 10K or 50K? Assuming these are just f...

I wish this was better documented, I can't believe I went so long without seeing this! It really makes my life easier I was a bit nervous about using this so i wrote some slightly silly test code to make sure it really does skip, and really does preserve the ACC value. Seems to work perfectly! ; if ...

Hi Frank, thanks very much for clearing that up! I found it on this page, at the end of the notes for RDFX: http://www.spinsemi.com/knowledge_base/inst_syntax.html#RDFX I also found a typo later on the same page, but for WLDR: http://www.spinsemi.com/knowledge_base/inst_syntax.html#WLDR "The fr...

Hello! I'm having trouble understanding RDFX. According to the syntax and instructions page,we can use it to clear the acc and load a register by writing "RDFX reg,1" The formula for RDFX is ACC=[reg]+(ACC-[reg])*K1 If K is equal to 1, we just get [reg]+(ACC-[reg]), and as far as I can tel...

For guitar, I feel like 3x or 4x input gain is best. You can go higher, but you're too likely to get clipping when using a high-output guitar.

Hello! I know that the frequency of ramp LFO's are set by the values -­16384 – 32767. What is the formula to convert a frequency in hertz to this value range?

I found the formula for the sine LFO in the "Basics of the LFOs in the FV-1" pdf, but couldn't find it for the ramp LFO.

Thanks!

Thanks for the info on using a sin for the LED.

Speaking of which, what are you guys using as drivers? A simple transistor circuit?

You seem to have sorted out your problem, but I thought I'd add that I've built over a dozen pedals using Tayda Crystals and they all work fine. Tayda lists the required Load Capacitance as 12.5pF (and the datasheet lists 9pf, 10pf, 12.5pf), and I've used both 10pf and 15pf capacitors which worked f...

The T092 package 78l33 has served me well, thank you for the reply!