U47xfet PCB from UTM / IGS?

[TimG]

So this is what I received from UTM for my UTM47LB Project.
Looks like it’s a little over $100 US with shipping to put it together, plus capsule.

And this is what the “f” transformer looks like up close.

FedEx tracking the whole way and signed for.

I got this TLM103 body from Alibaba for $30 US, delivered. I didn’t think it would come with the XLR connector but it did. (Look for loose screws in the box!)

https://app.alibaba.com/product/160...38a0b89a52c1676586966&prepage1=null&language=

I got this BOM for about $16 from Mouser. I always get something wrong somewhere but here is the Project.
https://www.mouser.com/ProjectManag...jectGUID=f130dc77-e85f-4443-8e8f-96cd81020cf4

Banzai
I ordered the Styroflex capacitors and the 2SK117 from Banzai for about $5, which I’m still waiting on.

SKU21152	Styroflex 100pF	€0,87	2	€1,74
SKU27397	2SK117	€2,27	1	€2,27

Happily I have a Flat 47 from Soliloqueen!

I am sure someone here is going to build theirs sooner than I will, so I’ll probably save the rest of the thread for my eventual build.

Fun to find a new offering and see if it is solid!

TimG


Putting the other info up top too.

The link to the UTM/IGS offering.
UTM47LB

https://utmindustry.com/public/upload/catalog/product/58/1675758361utm47lb_sch.pdf

1675758361utm47lb_sch.pdf

BOM from UTM

https://utmindustry.com/public/upload/catalog/product/58/1675758188utm47lb_BOM.txt





Hello!
I’ll be first. I got this on my fb. I’m looking forward to it.
Anyone built this yet??

 

[TimG]

From UTM on fb…

 

[klem]

Would be awesome if IGS allows for buying it without capsule and transformer.

 

[TimG]

We must be waiting on the UTM2547...I'd buy one with their transformer, for sure.
I've bought others from them and they were not expensive in USA. Have still to build with them.

Maybe in this ballpark? Their UTM0547 for U47?
https://utmindustry.com/utm0547
"A high performance, audio signal transformer for microphone level input applications. Useful for providing a -18 dB gain for any high impedance input. Suitable for any source balanced or unbalanced not exceeding 2.5kΩ.

Ratio: 6:1
Impedance: 8.5k:200
Frequency Response @1kΩ source 1kΩ load: +/- 0.3 dB 15 Hz to 80 kHz (Ap)
Primary Inductance: 645H@100Hz
Primary Inductance: 8H@100Hz
Total DC Resistance PRI: 390Ω
Total DC Resistance SEC: 34Ω
Max Level: @50Hz: +14 dBu
Mu-Metal, High Nickel Core, 79% Nickel Steel lamination
⌷

 

[TimG]

I got a note that this will be available via UTM soon. I’ll try one.

 

[bremusound]

Great, it should fit into these cheap chinese TLM 103 bodies.

 

[TimG]

Exactly for the TLM 103 bodies.
The link is live but I don’t see a UTM2547 transformer listed that you are to buy separately.
Or maybe they will encourage experimenting similars of the same size?

https://utmindustry.com/utm47lb?fbclid=IwAR0pNWZRXnE0g5_XYo7cciexfza_-Z4dV-0KoI8LKY44wIIpjXe5gwVhU0c
I’m ordering when I learn more about 2547 or ?
They have custom stickers for the body to use or not. But it comes with styrex.

Bill of Material for UTM47LB.PCB


Comment Pattern Quantity Components
------------------------------------------------------------------------------

.33u/50 CE 1 C6
0.1/100 C1M400 1 C4
0.1u/63 C1M400 1 C9
100M R1G 1 R3 - Included
100k R200 1 R17
100p C500S 2 C12, C13
10M R200 2 R8, R16
18p C 1 C2
1G R1G 1 R1 - Included
1u/50 CE 1 C11
1u/50Elna CE 1 C10
220M R1G 1 R2 - Included (2x100M)
22u/6V3 CE 1 C8
2SK117 T2_FET 1 T1
2n2 C500S 1 C1 - Included
2u2/50 CE 1 C5
33p C 1 C3
3M3 R200 1 R9
430k R200 1 R12
470k R200 2 R11, R13
47k R200 2 R10, R15
4M7 R200 1 R7
4k7 R200 1 R14
4u7/6V3 CE 1 C7
56 R200 2 R22, R23
680k R200 2 R20, R21
6k8 R200 3 R6, R18, R19
BC550 T2 4 T3, T4, T6, T7
BC560 T2 2 T2, T5
SIP6 SIP6 2 H1, H2 - Included
UTM2547 UTM2547 1 U1
XLR SIP3 1 ST1 - Included in mic body

 

[dmp]

Not the right transformer for a FET47.
The tube 47 and FET47 have different ratio transformers. The 0547 is a low ratio (6.5:1) for the historically correct U47 using the vf14 tube.
The FET transformer was higher, 9:1
Buyer beware UTM/IGS

 

[ZHOUJUN]

Great, UTM transformer is very cheap BV8 substitutes, can send a trial report? I want to buy a few to try.

 

[soliloqueen]

Listing says k47 capsule but that's a k67. Hmm

 

[TimG]

Listing says k47 capsule but that's a k67. Hmm

And I have a shiny new Flat 47! And a mic parts 47 (and 67).
Maybe it’s not a 47 per se. I’m sure they built a few before launching. It’s IGS!

 

[bremusound]

Will try it with the flat k47, knowing that an exact U47fet clone would need a different body, capsule and transformer.

 

[bremusound]

They now have a 9:1 transformer

https://utmindustry.com/utm0547f?fb...wCM6etExKRYSKkFTtuEXo2P9eekNy05nlonYM2_1bmIZQ

 

[TimG]

They now have a 9:1 transformer

https://utmindustry.com/utm0547f?fb...wCM6etExKRYSKkFTtuEXo2P9eekNy05nlonYM2_1bmIZQ

I’m asking that they ship me this newer arrival.

 

[bremusound]

They will. I asked for the same earlier today.

 

[igs]

Hello everyone,

Thanks for all your posts. After few early minor troubles we corrected the project today:
- Output transformer is UTM0547f, 9:1
- K47-style capsule on the photo
- New BOM and schematic uploaded

As somebody said on the Facebook thread, this mic is as good as the capsule used, so we strongly recommend the Thiersch M7.
As you can see on the name "LB", it's a Little Brother, Low Budget project, so the body is small and the cost is low. But the sound is really huge!

 

[TimG]

Before it get’s weird, I’ll post what I personally receive here, ret-edit the thread title and let’s start an appropriate thread if this is now a thing for sale.
How about that?

 

[TimG]

Updated at the top.

 

[EarthTone]

Hello everyone,

Thanks for all your posts. After few early minor troubles we corrected the project today:
- Output transformer is UTM0547f, 9:1
- K47-style capsule on the photo
- New BOM and schematic uploaded

As somebody said on the Facebook thread, this mic is as good as the capsule used, so we strongly recommend the Thiersch M7.
As you can see on the name "LB", it's a Little Brother, Low Budget project, so the body is small and the cost is low. But the sound is really huge!

View attachment 104545

This is a cool looking project. @igs how can we buy Thiersch M7? He doesn't respond to emails anymore... Do you stock them?

 

[igs]

This is a cool looking project. @igs how can we buy Thiersch M7? He doesn't respond to emails anymore... Do you stock them?

Sorry, I didn't know that. The last time I bought a couple of capsules was in March 2020.