KM84 DIY Body & PCB kit – CLOSED

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I'm also in for 2 kits of any second run that happens. Let me know! My luck is I'll next check this thread when the second run's spoken for and done.
 
Any word on when orders will ship for those of us that have already paid?
 
mhbunch said:
Any word on when orders will ship for those of us that have already paid?

All orders without transformers were shipped a long time ago.

For orders with transformers, we can only move forward once everyone has paid.
 
...not looking for names, just numbers. How many haven't paid, and can others purchase their trafos to move this along? I'm sure they could be sold later. Looks like there's plenty of interest for another round. I'm just sorta anxious to get to this build.
 
iturnknobs said:
...not looking for names, just numbers. How many haven't paid, and can others purchase their trafos to move this along? I'm sure they could be sold later. Looks like there's plenty of interest for another round. I'm just sorta anxious to get to this build.

It looks like we are mostly waiting on one person who ordered 15 transformers and hasnt paid. I am anxious as well and wondering the same thing.
 
Is there a quick and dirty way to set the bias? If someone could share what they are getting where R3 connects to T1 (2N3819).

I thought I was going to be able to finish one of these up tonight until I realized I didn't have the 470pF capacitors. I do have 330pF, but I've made all the effort getting everything else I might as well use what is specified on the BOM. Plus I already have to order more parts for another project. Looking forward getting these done!

Thanks!

Paul
 
Potato Cakes said:
Is there a quick and dirty way to set the bias? If someone could share what they are getting where R3 connects to T1 (2N3819).

I thought I was going to be able to finish one of these up tonight until I realized I didn't have the 470pF capacitors. I do have 330pF, but I've made all the effort getting everything else I might as well use what is specified on the BOM. Plus I already have to order more parts for another project. Looking forward getting these done!

Thanks!

Paul
I thought biasing was easy, but I ended up with two broken 2N3819.
I dont install the capsule and the spring and gave the mic the 48v from the xlr input.
Then I put a 1khz sinus though the 1Gohm resistor.
My oscilloscope I place on the JFET. Usually the same method like on the U87 build from Poctop.
But I ended up two times, with as I said, a broken JFET.
 
If you power up the microphone first and then connect something to the input, the gate of the FET will get a pulse of -46 V.
(The charge in C1) The FET may not like this!
 
RuudNL said:
If you power up the microphone first and then connect something to the input, the gate of the FET will get a pulse of -46 V.
(The charge in C1) The FET may not like this!

Hell no I,m so dumb !
Thanks Ruud for explaining it again.
With my u87 builds I first connect everything and then power it up.
Don’t know why I don’t do it with the KM84.
 
I haven't received my stuff yet, but should we start a build thread? I wonder if it might be difficult to look
for pertinent info in between all the "I'll take 2 on the next run" posts. Hats off to Banzai.
 

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