appiah4 wrote on 2020-05-08, 10:24:

As you said, one way to find out 😁

One last question, that wire going across the crystal - Is that for properly grounding the thing? And if so, is it soldered onto the crystal itself, or only to the PCB?

I think it is indeed for proper grounding, to avoid RF interference or so. Probably doesn't hurt to put a small blob of solder on top.

I can't seem to source the required ferrite beads locally:/ BOM lists 3.5x7.6mm for 110Ohm Impedence, the ones I can find are 3.5x5.3 for 64Ohm Impedence.. Better than nothing I guess, but still 🙁 I ordered, but will keep looking.

appiah4 wrote on 2020-05-08, 14:18:

I can't seem to source the required ferrite beads locally:/ BOM lists 3.5x7.6mm for 110Ohm Impedence, the ones I can find are 3.5x5.3 for 64Ohm Impedence.. Better than nothing I guess, but still 🙁 I ordered, but will keep looking.

110Ohm at which frequency? Here is the datasheet from the SnarkBarker BOM:

https://www.mouser.de/datasheet/2/150/2743004111-1513127.pdf

I don't know what the beads are there for. So it would be interesting what they are supposed to filter/suppress. You could probably replace them with something similar, as long as impedance is high enough in the needed frequency band. You might want to contact TubeTime directly, what those are for and what to replace them with.

root42 wrote on 2020-05-08, 14:29:

110Ohm at which frequency? Here is the datasheet from the SnarkBarker BOM: […]
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appiah4 wrote on 2020-05-08, 14:18:

I can't seem to source the required ferrite beads locally:/ BOM lists 3.5x7.6mm for 110Ohm Impedence, the ones I can find are 3.5x5.3 for 64Ohm Impedence.. Better than nothing I guess, but still 🙁 I ordered, but will keep looking.

110Ohm at which frequency? Here is the datasheet from the SnarkBarker BOM:

https://www.mouser.de/datasheet/2/150/2743004111-1513127.pdf

I don't know what the beads are there for. So it would be interesting what they are supposed to filter/suppress. You could probably replace them with something similar, as long as impedance is high enough in the needed frequency band. You might want to contact TubeTime directly, what those are for and what to replace them with.

The datasheet on Mouser says 126 Ohms at 100MHz but the product description says 110 Ohms at 100MHz. Looking elsewhere, I am led to believe the latter is true and the linked datalink is not for this exact part..

I will attempt contacting TubeTime indeed 😀 I just don't know how..

appiah4 wrote on 2020-05-08, 17:15:

I will attempt contacting TubeTime indeed 😀 I just don't know how..

He is pretty active on twitter. Otherwise, here is website: http://www.sonic.net/~schlae/index.html

I dont use Twitter but I got a reply from him bia email about ferrite beads:

Your alternative should work fine. The ferrite beads are only there to help prevent RF interference from conducting out through the speaker and joystick cables and are not critical.

We are go!

I still lack a lot of components but have around 2/3 of them now..

root42 wrote on 2020-05-08, 17:52:

appiah4 wrote on 2020-05-08, 17:15:

I will attempt contacting TubeTime indeed 😀 I just don't know how..

He is pretty active on twitter. Otherwise, here is website: http://www.sonic.net/~schlae/index.html

I'm also here on Vogons but I don't check it as often as Twitter.

Yeah the ferrites aren't critical for functionality at all, they were mainly so Creative Labs could pass their FCC tests. They prevent high frequencies (30MHz+) from escaping the computer through the joystick and audio cables. You could replace them with wire jumpers and the card would work fine (although, if your neighbor is a radio ham, they might complain).

TubeTimeUS wrote on 2020-05-09, 15:30:

root42 wrote on 2020-05-08, 17:52:

appiah4 wrote on 2020-05-08, 17:15:

I will attempt contacting TubeTime indeed 😀 I just don't know how..

He is pretty active on twitter. Otherwise, here is website: http://www.sonic.net/~schlae/index.html

I'm also here on Vogons but I don't check it as often as Twitter.

Yeah the ferrites aren't critical for functionality at all, they were mainly so Creative Labs could pass their FCC tests. They prevent high frequencies (30MHz+) from escaping the computer through the joystick and audio cables. You could replace them with wire jumpers and the card would work fine (although, if your neighbor is a radio ham, they might complain).

Hello there, apologies for bothering you via email I did not know you were a member..

Do you mind if I ask you (and others here) one final question? I have 270pF 1000V 5mm ceramic capacitors I can use, should I just use them or should I buy multilayer capacitors for C65, C68?

appiah4 wrote on 2020-05-09, 20:20:

TubeTimeUS wrote on 2020-05-09, 15:30:

root42 wrote on 2020-05-08, 17:52:

He is pretty active on twitter. Otherwise, here is website: http://www.sonic.net/~schlae/index.html

I'm also here on Vogons but I don't check it as often as Twitter.

Yeah the ferrites aren't critical for functionality at all, they were mainly so Creative Labs could pass their FCC tests. They prevent high frequencies (30MHz+) from escaping the computer through the joystick and audio cables. You could replace them with wire jumpers and the card would work fine (although, if your neighbor is a radio ham, they might complain).

Hello there, apologies for bothering you via email I did not know you were a member..

Do you mind if I ask you (and others here) one final question? I have 270pF 1000V 5mm ceramic capacitors I can use, should I just use them or should I buy multilayer capacitors for C65, C68?

No worries. Those caps ought to work, give them a try.

Uh further complication, it appears the RP1 2.2KR resistor network is actually isolated not bussed and the one I have on order is listed as 7+1 so I bet it is bussed... Meh 😒

solder a bunch of 2.2k resistors then 😁

It would look ugly as sin 😁

I may socket these resistor networks.. that way I can jury rig something for the moment...

Good news, I sourced the resistor networks, and ordered some SAA1099 chips from China. I now have everything except the Alps potentiometer that seems impossible to source for me yet, so that will be my next problem. Maybe I can find a way to temporarily bypass it?

For now, I've started soldering onto the board. Here is where I am after two days of work: (Yes, I am a noob and slow 😁 )

R15 is the wrong value!

Just kidding. Good job! Take your time, it's supposed to be fun!

keropi wrote on 2020-05-10, 18:19:

solder a bunch of 2.2k resistors then 😁

Oh wait, you were not kidding, the reference image actually DOES have 4 2.2KR THT resistors! And it doesn't look half bad, I really didn't need to sweat it this much. 🤣

root42 wrote on 2020-05-12, 07:41:

R15 is the wrong value!

Just kidding. Good job! Take your time, it's supposed to be fun!

Wait, what? NooOoo! Oh, ok then 😁

Kinda stumped about the potentiometer, mouser charges 20 EUR for shipping to me and it's not available on sale anywhere else I can find 😒 Could I just solder a 10K resistor between two of the wholes to set it to max for the time being? Or maybe something like a 6-7K to set at near half? I don't know..

Mouser usually ships for free for orders over 50EUR. Not sure about Turkey. I bought the whole Snark Barker BOM with Mouser and had no shipping costs (albeit for two SBs).

I think it would be enough if you found a small pot with similar layout. You could alternatively solder in two resistors for the time being. A potentiometer is kind of a voltage divider, right? So only one resistor wouldn't be enough I think.

root42 wrote on 2020-05-12, 08:55:

Mouser usually ships for free for orders over 50EUR. Not sure about Turkey. I bought the whole Snark Barker BOM with Mouser and had no shipping costs (albeit for two SBs).

I think it would be enough if you found a small pot with similar layout. You could alternatively solder in two resistors for the time being. A potentiometer is kind of a voltage divider, right? So only one resistor wouldn't be enough I think.

I ordered the other stuff locally so this would be a bit steep 😒

I don't hink it's a very simple bypass, the board uses a dual gang potentiometer.

What I can make of this circuit schematic is that I can solder two 4.7KR resistors between 1A-2A and 1B-2B, the connect 3 to Ground and have it at 50%? Obviously as it is reverse logarithmic I would probably get what, 30% or so? Alternatively I could use an 8.2KR and 2.2KR but I don't know which one should go where to get around 70% volume..

I followed the traces to label the terminals above..

I quickly checked, but I don't have any leftover pots. Sorry. I might be ordering from Mouser in the next few weeks though, and might order one or two pots for you and forward them via mail envelope.

I really appreciate your help - maybe you could just send it along with the bracket eventually and I would cover the shipping and price of the pot via PayPal?

appiah4 wrote on 2020-05-12, 10:59:

I really appreciate your help - maybe you could just send it along with the bracket eventually and I would cover the shipping and price of the pot via PayPal?

Oh yeah, I have to get back on the bracket thing! Yes, that would be an option.