How about carefully soldering a couple of leads to the chip PTC resistor and glue that to the ic. You can do this, and I have done so on a couple of occasions, and it'll probably work as well as any axial PTC resistor. Having said that I've always had better results using a larger resistor and larg...

I like my Neumann KH120A. Compact and beautifully constructed. It's worth investing in a pair of decent speaker stands too so you have them sat off the surface they're sitting on.

If using a tempco resistor with the eurorack DLF, is it recommended to glue the resistor to the transistor pair? I've never bothered with a filter. Indeed, I don't always use it for my own VCOs either. It certainly won't do any harm and it will improve thermal transfer between the components. If yo...

I'm doing it. But you have to build it yourself.

Could the diodes be the problem? This is quite possible as Eggpie found. Check the voltage on pin 7 of U4. It should go from -5V to +5V when the shape pot is turned. The diodes will have an affect on this signal. If either D1 or D2 are around the wrong way you'll get a much smaller range. And they ...

... I bought it from Analog Craftsman. I believe Tony customized it for me (I didn't need a power strip) but this is what the one looks like on their page (and sadly the mults are passive). Is it not one of Krisp1's utility panels? It looks a lot like one of my Control-X boards behind a 1U panel. T...

From the ramp output, with the waveshape knob full ccw I get ramp, at 9 o’clock triangle, then from 11 o’clock onward the saw. Check that you have a ramp wave on the output of U7 (pin 6). It should oscillate between 0V and +5V. Then check that you have a sawtooth wave on the output of U4a (pin 1). ...

adam wrote: ↑

Tue Jan 05, 2021 2:34 pm

I'm not sure if the 10k euro exemption threshold for small traders applies to 3rd countries or if thats only for people in the EU - thats turnover sent to eu countries in a year, not total, they brought that in for the knitting pattern vendors.

Adam, what's this 10K Euro threshold?

seems like it should be pretty straightforward once it's set up, you just make one lump sum payment of VAT regularly then it gets distributed to each country you've had orders from. Yes, I think once you've got VAT registered dealing with the IOSS is probably pretty straightforward. The nice thing ...

I'm not entirely sure you're right there - as far as I've picked up I (as a VAT registered company) now do not charge VAT except on UK sales. This is correct. However, the EU want you to use their Import One Stop Shop from July of this year if the order value comes to less than 150 Euro. It would h...

Maybe there is a way to reduce the shipping costs in a way that ordering single PCB's would stay beyond the VAT treshhold? Sadly it's only 22 euros and Adam says it will end in July. The EU and the UK are trying to stop the large volume of goods coming in from the Far East which sneak past border s...

adam wrote: ↑

Tue Jan 05, 2021 5:36 am

the small package exemption continues until july 1st, so small orders will still be free from vat

It's only 22 euros though and I think it includes the price of the postage. But either way, it's a not a big value and most of my customers' orders will be more than that.

I would expect the prices to be recalculated without VAT for export as it is done the other way round. There is no VAT applied on any products I sell. This is because I am not VAT registered. That means that I do not have to charge my customers VAT. UK businesses do not have to register for VAT if ...

oozitron wrote: ↑

Fri Jan 01, 2021 11:29 pm

The analogue delay (ADR-30) calls for two BC547C transistors.

The ADR30 uses BC549C and BC559C transistors. There are no BC547C used, although they would probably work just fine in place of the BC549C.

Tony

Back in the old days when I was young, uF (ie. microfarad) was often seen as mfd.

So we can now take this change as permanent (C2 = 220uF instead of C2 = 100uF)? I've not tried it but there should be no problems increasing C2 to 220uF. Whether there is a noticeable difference to 100uF I couldn't say. The law of diminishing returns will no doubt be true in this case. Within reaso...

I've changed C2 to 220uF on both filters and although it doesn't eliminate the bleed through it has almost completely gone so in practice is a non-issue. This is good to know. I will update the Builder's Guide to incorporate this change. My power leads are longer than they need to be so at some poi...

The two main mechanisms by which one module may affect another without patching are via the power supply wiring, and proximity. If both Journeyman modules are similarly affected then we can rule out proximity, as if this were the case the filter nearest the oscillators would have the worst bleedthro...

I actually get 20.2V between and AC pin and ground. Not 18V as I thought. This is quite normal. The PA-30 is a EI core transformer in a plastic casing. The output voltage will depend on input mains voltage which varies from country to country, and with time. The output voltage will also depend on o...

How do you choose a value in this specific application? I've not used one but I would think that the voltage needs to be high enough so it won't ever conduct in normal use (so somewhat more than 12V), but low enough to protect whatever is in the circuit. Something between 15V and 20V may suffice. I...

It's a TVS diode or transzorb. It's used to protect the module from some types of over voltage.

https://en.wikipedia.org/wiki/Transient ... sion_diode

What does that ChipQuick thing do? That Chip Quik kit has no tools as such. It provides a flux and a special solder alloy that melts at a very low temperature. The solder stays liquid way longer than any normal solder. So you apply the flux to the solder pads for the part you want to remove. Then r...

I used no-clean fluxed braid and no-clean solder. You're a braver man than me. I would have used the wiggle-break-replace method. These days I have a Hakko FR-301 which does the job nicely, even on four layer boards. Somewhat expensive for occasional use but brilliant for those bigger jobs like 40 ...

waldenpotato wrote: ↑

Sat Dec 12, 2020 11:14 am

It looks like I DID install the network backwards on the pot board. Shoot! I always try to be so careful.

You're not the first to do this. I think for the next run of these boards I will make these 9 pin SIL packed resistors individual 0805 resistors. Taking that front panel off is no fun.

How should I handle the cleanup when replacing the network? I figure I'll uninstall it and re-install a new one with the no-clean solder. Then I can spot clean with water around the install area. I also use water wash solder for the main part of the build, and then use no-clean solder for the pots ...