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Mylar (aka Polyester, PET) has higher temperature drift, but not sure how much exactly (I’ve seen numbers from +200ppm/C to ±5%, and the datasheets for the ones I usually use don’t specify it at all, what I can see). But better than class II ceramics, afaict.

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My understanding of the meaning of the “P” in the Y5P capacitor code is that the the capacitance at any given temperature within the operating range can be different from the capacitance at 25C by as much as +/- 10%.
So an exaggerated worst case example would be that at -15C it’s 10% above the 25C value and at 40C it’s 10% below the 25C value. That would represent a 20% change capacitance (and thus in pitch) from the sound check tuning right out of the truck and the heath of the concert.
That’s like a 440Hz A4 becoming a tree semitone higher C5. Definitely audible

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The ceramics:
Y5P

Y=-30°
5 = +85°
P = ± 10%

The TCC for an Y5P is ± 10%
1000pf * 0.1 = ±100pf maximum capacitance change

So this capacitor at temperatures above or below 25° can be as high as 1100pf and as low as 900pf

You can probably just use a piece of wire. Or if you so prefer, something decorative:

Q: The analog synth circuit I’m building calls in the schematic for ferrite beads on the power rails, but it doesn’t give any further information. What kind of beads should I use?

A: Pick some that will look nice on the board, maybe in a colour that goes with the solder mask. Your local craft supply store should have a good selection of decorative beads, like these glass ones I got in a clearance sale.

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has anyone got a good source for Blank black circuit board, unprinted for use as a panel instead of aluminium ??

It shows you how easy it can be to make your own custom boards. You dont have to be content with just a plain black board that you have to drill etc. Just CAD them holes and add them graphics.

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Most excellent, thanks for pointing me to this post !!

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@Pontifex Notes & Volts posted a short series on exactly how to create boards from start to finish with kiCad. The first video in the series is here.

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great series of tutorials, thanks

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I just got 50 cent 1n mica capacitors and 15 cent .1% resistors for the VCOs at local Anchor Electronics. They also do mail orders and have all kinds of other fun things.

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dam all these F#%*ing borders , just to keep the people in power , in power . when we all get along fine and just want to make noise / music … oops sorry a bit to political , but that customs shit empties pockets and slows us down .

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I sent of the letter to customs to try to get a refund…

Cost me £1.50…

Because my value was £16.40 (or something) it was over the £15 low threshold.

I don’t remember reading anything otehr than values over £130…

So Customs gets £4 for something that costs the same in the EU.
Royal mail gets £8 for 10 seconds work slapping a lable on and calling it Handling!
Royal mail get a further £1.50 for me to send what could be provided by online form…

So my 3340’s have not been cheap.

I have actually started buying more small components direct from the UK since Christmas, the cost difference with China is not huge on these and they turn up next day, and if they don’t turn up replacements are not another 6 weeks off… And with Chineese new year and Corona it’s become more random…

Rob

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New Tayda discount code:

15% Discount Coupon Code : “Sale15”
**Valid till 27 February 2020 ( 11pm New York time )
**Valid to use only on www.taydaelectronics.com
**Please make sure to apply discount coupon during checkout, we can’t apply it manually after checkout is completed.
Happy Shopping!
Thank you for choosing us.

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Classic big knobs A-1996 from Tayda are not fitting the 6.35mm round shafts FYI, anyone else have this problem? The smaller ones fit just fine but no dice on the big knobs. Trashed a rotary switch petting the rabbit to hard.

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I hate to ask what may sound like a completely snotty question, but it looks to me like it has a rubber knurl that you have to take off off and let out the set-screw before trying to put it on-did you do that?

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Hmmm I will have to check when I get to the house. It looked to me that the insert is smaller, I hope your right since I bought 20 of them. Thanks for the heads up. Please don’t worry about snot I’ve played synths for years but I’ve never tried to build one until now haha!!!

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Yeah the tolerance is different, I can probably role up a little sandpaper and take care of it.

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I have had some success with a drill press to go from 6mm to ¼”. Really only works well with larger knobs.

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Yeah going to drill this out and work on the knobs tomorrow, hopefully it will work.

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JACK SOCKETS I can confirm these are nice from mouser https://www.mouser.co.uk/ProductDetail/REAN-Neutrik/NYS232?qs=%2Fha2pyFadugmnx0kZ8I0yxhALEezTEMSgSeTGJnT%2B4ByD9HE33EqVg%3D%3D

I ordered a few different ones from mouser to see as the description and data sheets dont always match up but these are good!

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