Ordering NEOVibe parts...what do i need to know

[sjaltenb]

Ok yall i finally decided i wanted to build the NeoVibe. I am going to order the PCB from GGG. I used the stocklist and I am ordering from Mouser.

I have so Far:
All resistors-metal film except for the 1.2 and 2.2m, those are carbon film
All electrolytic caps as listed
All Film caps as listed
The trim pot as listed
Bridge rectifier as listed
diodes as listed
transistors- 2N3904TA
L7815ACV      ST Voltage Regulators
the two switches
2x 100k audio taper (is this right?)
50k audio taper

I am using 9V power supplies in my cornish board, is there any way i can use these to power the NeoVibe or do i need to get an 18V DC supply as well?

Can i make this a 3pdt with an LED?? What about the LDR and bulb? Smallbear? if so which ones do i buy? Thanks so much! really looking forward to this project!

[smallbearelec]

Drop me a message at the smallbearelec address, and I will reply with a spreadsheet that lists everything. I can supply all except the wall wart.

If you want the speed pot to work in the expected way, i.e., lowest speed at the counterclockwise end, you want a dual reverse audio 100K pot, my SKU 1004.

Reports on the "best" lamp(s) and photocells have varied here. The bias pot can be set to accommodate a variety of lamp voltages from 1.5 to 28. See previous threads for suggestions. I can supply the photocell that Mouser obsoleted, my SKU 2500, or I just got some hermetically-sealed Silonex NSL-7530 that will be posted as soon as I can find time to take pics.

SD

[sjaltenb]

That would be GREAT!!!

I have been a pretty steady customer of yours lately with all my BYOC effects. Sorry about the confusion on that last order!  I would MUCH rather order from you than from mouser.

I will drop you that email

[wlrs]

I found the 100K volume pot kills allot of swirly liquid sound of the pedal and using a 250K works allot better. If you are using one of those 1.5 volt bulbs and it keeps blowing out you can try this one http://www.radioshack.com/product/index.jsp?productId=2102815&cp=&pg=4&sr=1&origkw=bulb&kw=bulb&parentPage=search
and double up the 2n3904 for the driver or can use a 9014 transistor its not a 2n9014 but just a 9014.The 2n3904 gets hot but the 9014 wont. I also like to use matched transistors this is big deal in these pedals and RG has a simple tester you can build for doing this.One other thing is the LDR's they make all the difference in the world I would say more then anything I have not used any LDR's from small bear but I have from allot of other places and this is as close to the real univibe as I can find.. They are a little pricey but they sound better then anything I have tried thus far
http://www.alliedelec.com/Search/SearchResults.asp?N=0&Ntt=VT33N2&Ntk=Primary&i=0&sid=47607600739D617F
I'm not trying to take anything from small bear they are great people and their prices are fair I'm just giving you some tips as to what will improve the sound of you neovibe and make it sound like the real one does.
The walrus

[BubbaKahuna]

WLRS, would the 50mA versions of those Radio Shack bulbs work?
Reason I ask is that the 25mA ones have wire leads, but the 50mA bulbs have nice straight/stiff pins for leads.
They look a lot easier to solder onto the board.

Cheers,
- JJ

[Solidhex]

ahhh

  I too am ordering parts for the neovibe... I have most of the pcb populated with the jumpers and transistors. I have some ldr's from electronic goldmine I plan on using.     A friend of mine gave me a huge box full of all sorts of components. Most I can't even identify. Today I found some Clairex CL-3 crystal photocells. At the photocell end they almost look like they're sealed in a sort of oxblood red waxy material...anyone familiar with these? Would they be decent enough for Univibe use?
  Its definitely one of the most involved pedals parts-wise I've tried to build... its not often you have to buy copper sheeting and tin snips for a pedal! Looking forward to getting this thing vibing...

--Brad

[RedHouse]

...The 2n3904 gets hot but the 9014 wont.... I also like to use matched transistors this is big deal in these pedals and RG has a simple tester you can build for doing this.

Not to derail the thread but...

>The 2n3904 gets hot
The 2N3904 is a 100mA transistor, it shouldn't be getting hot with a 25mA or 50mA bulb in the LFO/Bulb driver circuit, there must be something else going on in your vibe builds to find that an issue. I'm not guessing either as I've used 2N3904's in a dozen builds (yes, one build was a Neo, so that's not why) and still use them when doing a retro/vintage type circuit (of my own, my modern builds use 2 MPS-A13's in the LFO)

>use matched transistors this is big deal in these pedals
This matching transistors thing, WTF?

None of the transistors need to be matched in a univibe or clone, even the darlington pair in the LFO doesn't need to be a matched pair. Sometimes builders find their LFO won't start, or fails to keep going with transistors with too-low gain (talking roughly hfe=200 and less) and is why most folks order 2N5088's for the build, and a few 2N3904's for the bulb driver.

2N5088's work great in the audio path and have high enough gain to keep the LFO working reliably, while the 2N3904 (with an Ic=200mA) works better as the bulb driver but still shouldn't be getting hot.

While indeed the whole vibe circuit can be built with 2N3904, I would submit that the 2N3904 is best suited for the bulb driver, either by itself (RG-neovibe) or in darlington configuration (JC-vibe+). It's just not necessary to match transistors for a univibe.

...Now, back to your regularly scheduled programming...   

[Solidhex]

Yo wlrs...

  I actually happen to have a 250k log pot I was planning on using for a fuzz face volume pot. I of course would be interested in getting the maximum amount of "swirl" out of my Univibe. Why would a 250k have that effect?

--Brad

[Dai H.]

I just ordered a GGG board also and need to buy some of the other parts like the bulb and photocells. That Radio Shack bulb which is listed as 1.5V is kind of confusing but after searching I found that I can apparently obtain a 28V 40mA bulb locally which someone measured at 70ohms which seems pretty close to an original. There's also some info about matching the photocells which I'd like to find more info on to know if this is important. Re: the dual pot, in R.G.'s tutorial a dual 100k is listed but on the original schematic at JC Maillet's site shows 250k (appears to be "250k VR" on the schemo. The 50k pot also looks like "50k(B)" on the schematic but in the tutorial it's audio taper. I was planning on just putting the daul pot control on the enclosure as a knob and try to add a pedal later. Also want to check out if the bypass position does anything to a wah output.

[BubbaKahuna]

I also bought photocells from Electronic Goldmine and they're all over the place on values. No 2 are even close to each other in resistance when measured under complete dark or bright light. The ranges in dark/light are 400k/.37k, 40k/150, 1.2M/.2k & 2M/40k. Pretty much worthless for a vibe with that kind of a spread. I tried Radio Shack for photocells, but they only have a 'selection' in a package and they're not even the same size from one to the next and don't give a listing of values.

At least EG refunded the cost of the 3 photocells that don't come even remotely close to the product description. I've found some of their stuff to be kind of hit or miss in values, but they've always refunded for anything that didn't match what it's labeled as or they describe as.

Cheers,
- JJ

[Solidhex]

Yeah

  My goldmine photocells didn't work out as I would've hoped. Small Bear here I come. I'm still curious about the 250k volume pot. Can anyone shed some light on why you would get more swirl from it?

--Brad