Neovibe resistor question

[GonzoBonzo]

Hey Guys,

  I'm currently putting together the parts to build a Neovibe, and have a question about one of the resistors.  According to the schematic from the neovibe update PDF,  R49 is showing a value of 4.7K.  The Forum vibe R49 value for the vintage vibe is 47K.  Whats the correct value for the original R49?

TIA

Gonzo

[kymar]

i tried both, 4k7 sound better

[GonzoBonzo]

Is that 4.7 or 47K?

Thanks Kymar

[R.G.]

"4K7" is one way to write 4.7K. It eliminates issues over the decimal point being lost.

However, I believe the original value was 47K and either I saw an orange band as a red band on a Univibe when I repaired it or it got transcribed incorrectly.

The specific value may not matter, as the only thing this does is prevent the lamp driver from overloading and stopping the LFO. A lower value lets more LFO signal voltage/currrent reach the lamp driver and drive it harder.

It's funny how tastes change. When I originally did the first PCB that would become the Neovibe, I released it on usenet. This was before the web interfaces we use so much even existed, probably in 1993. I need to go check that date; I think I still have the original files. But when I did that, I was roundly taken to task by some people on usenet for making it non-original in every way, and told that it simply could not sound like the original. This for replacing the half-wave rectifier and R-C filter with a full wave rectifier and three terminal regulator. Today, the first thing someone asks is "is this, or that orignal?" followed immediately by "anybody got any mods?"

[kymar]

look at this, i also think its a red band

Hi.
Can anyone confirm that R46 is 47K? In the original schematic is 4K7 and these are very different values...

Ok. I answer myself:


4K7, as you can see.

[GonzoBonzo]

Thanks for the answer R.G.,  and your work putting the project together.  I wasn't too concerned about it being original, more so if it will work without blowing up.  I know some of the original parts are not available anymore, so compromises must be made.  I'll try sticking to the layout, but have no problem modding it if I have to.  I'll be using a 12V, 40mA bulb, and NSL-7530 LDRs, so I may have to add the offset,  driver mod, and fiddle with emitter resistance.

Thanks again for the response,

Gonzo

[GonzoBonzo]

Man, you have better eyes than me.  Can't tell by that photo.  Great pics though.  Just looked on the Univox site, and the schematic on there is showing 47K.  Who knows?    I'll try both.  As long as the driver tranny doesn't blow up, I'll use the one that works the best.

Thanks,