Thonk VCA

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davel
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Thonk VCA

Post by davel » Fri Apr 11, 2014 11:08 am

Hi All,
Am trying to find a source of 1KTC SMT for the board I got from Thonk.
Does any one know who sells them. I did wonder if two 2ks in parallel would do but the ones I have are wire ended and about 1/2 watt.

Davel

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pre55ure
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Post by pre55ure » Fri Apr 11, 2014 12:33 pm

Hi, welcome to Muffs!

It would be helpful if you could describe the board and component a little better, or barring that maybe post a pic.

I'm guessing this is a 1k smt resistor that you are looking for?

Two 2k's in parallel should work, wattage won't matter as long as it's high enough (1/4 is pretty standard modular synth level) and you can get them to fit.


anyway heres the mouser number for something that might work (if you are looking for a 1k smt resistor)

mouser part # 71-CRCW12061K00FKEB

davel
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Thanks

Post by davel » Sat Apr 12, 2014 3:48 pm

Well thanks for that, but 1KTC SMT was all that was on the BOM, that was posted on muffwiggler, the screen print measures about 2mm x 4mm.
I will investigate Mouser, as I couldn't find any at RS or Farnell.

Thanks once again.

DaveL[/b]

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negativspace
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Post by negativspace » Sat Apr 12, 2014 4:17 pm

He's probably talking about my VCA:

Image

The tempco part at Mouser is HERE.

You can substitute a regular 0805 1k resistor if you don't want to bother/can't find them in the UK/etc.

davel
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Me again

Post by davel » Sat Apr 12, 2014 4:19 pm

I did wonder if the TC of the 1KTC SMT was a Tempco and not just an SMD 1206 resistor, as the board screen print is "tcr" but why use a SMD when the rest of the board is through hole. May be Manhattan has a big box of 1k, 1206 SMD Tempco resistors to get rid of.
The Board is the Manhattan Analog VCA v1.2 that I got from Thonk, but to look on muffwiggler to get any info on it, rather odd, I thought.

Regards Davel

davel
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Post by davel » Sat Apr 12, 2014 4:33 pm

Yes that's the VCA Board in question, thanks for the that Mr Negativspace.
Does KS = Kansas.

Regards Davel

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negativspace
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Post by negativspace » Sun Apr 13, 2014 2:04 am

You're quite welcome! And yes, it does.

Through-hole tempcos are much harder to get than the SMT variety and far more expensive. This is going to be a production module for me so parts cost was always a consideration in the design process.

Board space was also at a premium with this one...

davel
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Matched Pair

Post by davel » Wed Apr 16, 2014 12:12 pm

Hi there Mr Negativspace.

In the BOM for the VCA, the two transistor pairs are listed as matched.

Are they matched for hfe or vbe or both.

Regards Davel

davel
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Post by davel » Wed Apr 16, 2014 1:51 pm

Sorry I meant the Manhattan CP-3 Mixer matched pairs not the VCA.

I must pay attention when thinking.

Davel

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Manhattan CP-3 Mixer

Post by davel » Wed Apr 16, 2014 4:46 pm

negativspace

Hi there Mr Negativspace.

In the BOM for the CP-3 Mixer, the two transistor pairs are listed as matched.

Please, are they matched for hfe or vbe or both.

Regards Davel

elavrna
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Post by elavrna » Thu Sep 26, 2019 8:13 am

negativspace

elavrna
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Post by elavrna » Thu Sep 26, 2019 8:14 am

Hello - can someone please tell me if the v1.4 PCBs need the trace cuts and modifications required for the v1.2 boards?
Having trouble getting sound output though it is calibrated accurately and has no obvious issues. Any help appreciated.

SORRY - I see that this was answered earlier.

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