1073 4v caps

[wells2p]

Having a hard time finding 4v caps for 1073 mic pre and eq amps eg 125u/4, 400u/4, 64u/4v.

Were these simply commonly available parts at the time or does the low voltage rating have some significance. I can’t think of any but please chime in if it matters for some reason

I looked at the EZ1290 assembly guide and noticed some substitutions were done on the electrolytics which I was able to find but interestingly they kept the 4 volt caps in the schematic. Not sure about the BOM

Thank you

 

[Khron]

Nowadays you might still find 4v caps, but more likely in the aluminium polymer ranges of ultra-low-ESR ones, meant for high-frequency high-current power supplies.

Just go with the more standard 6.3v rated ones (or higher, up to whatever still physically fits onto the PCB).

More common values would be 120uF, 390uF (or 470uF) and 68uF. Although values from the E3 series should be easiest to find.

https://en.m.wikipedia.org/wiki/E_series_of_preferred_numbers#E3

 

[wells2p]

Thank you!

 

[wells2p]

Nowadays you might still find 4v caps, but more likely in the aluminium polymer ranges of ultra-low-ESR ones, meant for high-frequency high-current power supplies.

Just go with the more standard 6.3v rated ones (or higher, up to whatever still physically fits onto the PCB).

More common values would be 120uF, 390uF (or 470uF) and 68uF. Although values from the E3 series should be easiest to find.

https://en.m.wikipedia.org/wiki/E_series_of_preferred_numbers#E3

So as long as it fits on my PCB a higher voltage is OK? For instance 10, 16, or even 25v in lieu of 4?

 

[Khron]

Yup. More never hurts; less has a greater chance of going "poof" (or "pop").

 

[wells2p]

 

[Whoops]

So as long as it fits on my PCB a higher voltage is OK? For instance 10, 16, or even 25v in lieu of 4?

Yes, that spec is the operating voltage limit, so no problems in using a cap that is rated for an higher limit.

Also new caps are smaller that older caps for the same voltage, so a 16v cap might be the same size of a 4v caps even though it’s rated (sturdier) for an higher voltage

 

[wells2p]

The other issue is not all the original electrolytic values are common anymore eg 20u 64u 80u and 125u.
Assuming 22u, 68u, 82u, and 120u are close enough and won’t have any audible affect on the cutoff frequencies?

 

[warpie]

The other issue is not all the original electrolytic values are common anymore eg 20u 64u 80u and 125u.
Assuming 22u, 68u, 82u, and 120u are close enough and won’t have any audible affect on the cutoff frequencies?

Yes. These caps have 20% tolerance anyway.