Fraudhacker - cap questions | regulator question

[jessenator]

Couple questions about a couple caps on the Fraudhacker

CAPS
1. the 5pF cap (C29) —I swear I ordered some, but didn't—I have some RadioShack grab bag 7pF caps; will those work or should I get marked-5pF caps?

2. the 33uF (C26, C27, C35) caps —I thought I was buying electrolytic caps, but apparently I have tantalums, and apparently those aren't polar? should I go back to the order place and get electros?


REG
the regulator, the 78L05— I have a bunch of the L78L05CZ regs from STM. It looks like just the I and O pins are swapped, so could I just rotate it and use it? I'm not sure if there were any other specs to look at on the original intended part (don't know what specific reg is reference). https://www.st.com/resource/en/datasheet/l78l.pdf


Thanks

[mauman]

1. Don't know, so I'll pass
2. Tantalums ARE normally polarized, there's a tiny little "+" on one side to indicate the positive leg.   Unless you bought specifically "bipolar" and then it doesn't matter.
3. Yep, it's fine, 100 mA, 30V input max, just flip it around.

[madbean]

1 - Sure, a 7pF would be fine there.
2 - Tantalum would actually work fine as well. For C26 and C27 the are arranged correctly to use tantalum as a sub. C35 could be any value. 10uF, 22uF, 47uF. Even 100uF.
3 - As long as it's a regulator the pin configuration doesn't matter so long as you put it in the right way.

[madbean]

1. Don't know, so I'll pass
2. Tantalums ARE normally polarized, there's a tiny little "+" on one side to indicate the positive leg.   Unless you bought specifically "bipolar" and then it doesn't matter.
3. Yep, it's fine, 100 mA, 30V input max, just flip it around.

Jinx, bro!

[jessenator]

2 - Tantalum would actually work fine as well. For C26 and C27 the are arranged correctly to use tantalum as a sub. C35 could be any value. 10uF, 22uF, 47uF. Even 100uF.

2. Tantalums ARE normally polarized, there's a tiny little "+" on one side to indicate the positive leg.   Unless you bought specifically "bipolar" and then it doesn't matter.

Haha! Jinx, indeed.

I thought it was really odd there were no markings on them, too.
https://www.taydaelectronics.com/33uf-16v-radial-tantalum-capacitor.html
The MK-168 doesn't show polarity :/ so I can't tell that way. They do have a longer/shorter lead, so I'll pop them in accordingly just in case.


Good to know about the ceramic cap and the regulator, too! Thanks, gents.

[mauman]

Jinx, bro!

You got me!