U67 Build

[Khron]

So that's at least fourteen(!?!) teflon pins (that are visible), so we're up to ~30eu just with those... Cool then...

 

[dmp]

The teflon pins are expensive unfortunately. Some think you can skip this since modern PCBs have very high impedance.
Or if you want to cut costs, I'd suggest buying teflon tubing and making them yourself. Use resistor cutoffs with short pieces of teflon tubing.

But it's DIY so anyone can do whatever they want.

 

[kingkorg]

The teflon pins are expensive unfortunately. Some think you can skip this since modern PCBs have very high impedance.
Or if you want to cut costs, I'd suggest buying teflon tubing and making them yourself. Use resistor cutoffs with short pieces of teflon tubing.

But it's DIY so anyone can do whatever they want.

And in the end all the critical connections end up connected to the pcb through the switch terminals? Or am i missing something?

 

[dmp]

Pad and position are drilled out larger, unplated, and the wire connections are on the switch terminals

 

[Drosselmeier]

My version of the boards for the body SYT-5

 

[garp]

I modified a U397 (French Radio France version of the U77) years ago with the now discontinued max Kirshner's pcb kit from studio939. After little effort it was perfectly fitting the original body. The design and layout is also closer to the original than dan's pcb and the sound of the microphone is outstanding. The problem is that i want now modify all the U397 and vintage bucherised U87 i own, but can't find any PCB available. I began to mess with Kicad but i stopped at some point lacking of knowledge to finish this project. Can someone help here ? PS: i am living in south of france

 

[garp]

Here is a render of the project with certainly load of errors. I can provide all kicad files if some one is interested in helping for this job. The result will be of course available to everybody here for free

 

[Drosselmeier]

My version of the boards for the body SYT-5
View attachment 127840View attachment 127841

Spoiler: :-O

 

[garp]

Available for fellows like me ?

 

[Okimy123]

I have, possibly a rookie question... I'm looking at the 67 builds and they're asking for 400meg resistors, I've gotten everything else I need but am i dumb here? I've done a couple other builds but cant seem to find these values...

 

[Khron]

I have, possibly a rookie question... I'm looking at the 67 builds and they're asking for 400meg resistors, I've gotten everything else I need but am i dumb here? I've done a couple other builds but cant seem to find these values...

Just about anything goes - your best bet is probably 470meg (a standard E6 value), if 390meg or 430meg can't be found.

https://www.mouser.fi/ProductDetail...=sGAEpiMZZMtlubZbdhIBIFho3SHfDXStbowBqeLHeqs=

Same goes for the "60meg" ones - 47meg / 56meg / 62meg / 68meg are just as good, but are standard values that CAN be found nowadays.

 

[HerbertR]

There are also tons of them in China...
https://a.aliexpress.com/_EGCgIsJ
I hope that your country will be handed over … BR

 

[Geariatric]

I have, possibly a rookie question... I'm looking at the 67 builds and they're asking for 400meg resistors, I've gotten everything else I need but am i dumb here? I've done a couple other builds but cant seem to find these values...

If/when I’m feeling particularly compulsive about trying to get a weird value, I usually dig into my lower tolerance carbon film resistors hoping to find enough deviation for a close/exact match.

Although, I must admit, I’m often ‘disappointed’ to find them much closer to spec than I’d hoped.

 

[Okimy123]

Just about anything goes - your best bet is probably 470meg (a standard E6 value), if 390meg or 430meg can't be found.

https://www.mouser.fi/ProductDetail/TE-Connectivity-Holsworthy/RGP0207CHJ470M?qs=sGAEpiMZZMtlubZbdhIBIFho3SHfDXStbowBqeLHeqs=

Same goes for the "60meg" ones - 47meg / 56meg / 62meg / 68meg are just as good, but are standard values that CAN be found nowadays.

ok, I've managed to find everything else. Just not that. and I know these mics were designed with 5 or 10% tolerance to it shouldnt be an issue. just factory lead times for shipping things can be a problem sometimes lol

If/when I’m feeling particularly compulsive about trying to get a weird value, I usually dig into my lower tolerance carbon film resistors hoping to find enough deviation for a close/exact match.

Although, I must admit, I’m often ‘disappointed’ to find them much closer to spec than I’d hoped.

hahaha I'm the same. I started just picking up random carbon comp resistors and misc things when im working on some builds. I picked up the 470megs wihch should give me a solid device still. I made a DI a few months back with an old Jensen output transformer from some tube console and used such bizarre values that on paper it shouldn't work but gives me such a nice brown vintage tone to it... I may actually change them up for the hell of it.

 

[Khron]

ok, I've managed to find everything else. Just not that. and I know these mics were designed with 5 or 10% tolerance to it shouldnt be an issue.

Just not which "that"? Some might say i'm great or whatever, but i definitely can't read minds

Even before worrying about component tolerances, it's useful to be aware of the ROLE the respective components play in the circuit. In some cases, things work 95% as well, across several orders of magnitude (10k vs 100k for a resistor, or whatever).

 

[Okimy123]

Just not which "that"? Some might say i'm great or whatever, but i definitely can't read minds

Even before worrying about component tolerances, it's useful to be aware of the ROLE the respective components play in the circuit. In some cases, things work 95% as well, across several orders of magnitude (10k vs 100k for a resistor, or whatever).

ooh sorry, the 400meg. but yea i only try different things on passive circuits. like passive DI boxes etc. I try and stick to general rules of circuitry when working on active gear.

 

[Khron]

general rules of circuitry

And those are...?

 

[Okimy123]

And those are...?

making sure tubes are properly biased, op amps have correct circuitry, stuff like this. proper calculations for what kind of bass roll off i want or what inductance I need.

 

[Whoops]

Hello,
I have a lot of Feed Through capacitors for U67 builds,
send me a PM if you need some for your builds:



These are the Feed Through capacitors as used in the original U67's:

 

[OneRoomStudio]

there are 2 versions of the Chinese u87, one is a little more expensive, the other is cheaper

Interestingly, the “Circuit Diagram 06” versions seem to have disappeared (at least, I can no longer see them on AliExpress from the US), and the handful of sellers I have asked about them all insist that “it’s only a sticker, there is no difference” (which clearly isn’t true).

I wonder what the deal is.