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Why are good capacitors so expensive, and why don't they make these any more?
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Zero999:

--- Quote from: MathWizard on December 31, 2023, 10:32:35 pm ---
--- Quote from: CatalinaWOW on December 31, 2023, 07:12:40 pm ---Perhaps you can take a baby step into SMD by buying/designing a carrier that doesn't have a ton of capacitance or inductance.  It is easy to imagine something that would end up resembling a disc capacitor. Not elegant, but lets you do SMD on a very small scale to start.

--- End quote ---
Of my SMD parts, 1206 size and sot-23 BJT's seem it fit ok between the pads on my perfboard. And all the parts I checked, matched very close to their rating. So now I'm going to make a common-base Clapp oscillator, and compare it to the through hole part version I made last week.

--- End quote ---
That's what I do, as mentioned above.

For SOT-23 transistors or ICs, I use a drill to cut the track, solder pin 3 to the uncut track and pins 1 & 2 either side of the hole when the cut in the track is. I also do the a similar thing with SOT23-5 and  SOT23-6, with the four outer pins soldered between the cut tracks. I connect the middle pins to other tracks with short pieces of thin wire.
MathWizard:
Well with standard, 1 sided ring-pad perf-board, and 1206 parts, I used my strong flux, and it got under the parts ,and there's a bit of DC leakage messing with the biasing. I used steel wool on the perfboard 1st, so I should have used my safer flux. Without extra flux the wetting takes too long, and doesn't spread the solder near as good.

And 1206 was a little over sized. So I just made an 0805 amplifier circuit, and those fit much nicer between the ring pads, without overlapping.

But what I did 1st this time, was tin a pile of pads, but that filled them all in, so I had to go back with solder wick to remove most of it. Then to get nice clean bonds, I tinned all the parts too. Then I just had to lay them in place and tack 1 side at a time, and check resistances before adding caps.

But yeah I'm quite happy with that. All my SMD parts are cheap ebay/amazon ones, and they are all way closer to their ratings. And have lower parasitic's too, are and cheaper.

I have lots of breakout boards for chips or transistors if needed. I have some Dremel accessories that might make cutting up copper clad boards easier, but I haven't tried any of them yet.
TimFox:

--- Quote from: coppercone2 on January 01, 2024, 01:27:26 am ---
--- Quote from: TimFox on December 31, 2023, 11:25:06 pm ---So that’s what they’re calling them now.
Those are “disc ceramic capacitors” in 20th-century English.
Under that name and Ceramite brand, I used that exact series for RF purposes before retirement, and they worked very well.
A factory engineer gave me the power dissipation ratings for the different sizes, but I have lost the values.

--- End quote ---

careful they have disk MLCC

those are SLCC

its a monolithic structure vs a cuban sandwich

--- End quote ---


The “disc ceramic capacitor” is a disc of ceramic dielectric material, metallized on both flat sides, with wires soldered to the metal layers, then dipped with insulation.  They are still useful for working voltages impracticable for MLCC construction.
Most ceramic caps nowadays are MLCC, with a monolithic structure stacking multiple layers of metal and ceramic.  This new term SLCC seems to be a retronym for the older construction.  A MLCC with wire leads and axial or radial construction is not a disc, but quite useful for reasonable voltages.  I like the mil version (e.g. CCR06) with molded square plastic housing, since they look appropriate when fully seated against the PCB, but they are more expensive than the conformal packaged units that work equally well, but look less neat.
Another nostalgic NP0 ceramic cap is the “dogbone” style found in Tektronix ‘scopes.
coppercone2:
look at this one.
 
IDK if its a MLCC or a SLCC misrepresented as a MLCC

https://www.meritekusa.com/products/capacitors/high-voltage-ceramic-disc-hv-series/

I also had a round blue one that did not look like the little pillow but claimed to be a MLCC, even with the SLCC shape. It was fatter then a typical disk cap, blue, but IIRC the data sheet said it was a MLCC.
Zero999:

--- Quote from: MathWizard on January 01, 2024, 05:27:18 pm ---Well with standard, 1 sided ring-pad perf-board, and 1206 parts, I used my strong flux, and it got under the parts ,and there's a bit of DC leakage messing with the biasing. I used steel wool on the perfboard 1st, so I should have used my safer flux. Without extra flux the wetting takes too long, and doesn't spread the solder near as good.

And 1206 was a little over sized. So I just made an 0805 amplifier circuit, and those fit much nicer between the ring pads, without overlapping.

But what I did 1st this time, was tin a pile of pads, but that filled them all in, so I had to go back with solder wick to remove most of it. Then to get nice clean bonds, I tinned all the parts too. Then I just had to lay them in place and tack 1 side at a time, and check resistances before adding caps.

But yeah I'm quite happy with that. All my SMD parts are cheap ebay/amazon ones, and they are all way closer to their ratings. And have lower parasitic's too, are and cheaper.

I have lots of breakout boards for chips or transistors if needed. I have some Dremel accessories that might make cutting up copper clad boards easier, but I haven't tried any of them yet.

--- End quote ---
I only use the adaptor boards for SOIC.

I fit SOT-23 parts directly to the board, with the tracks cut to make them fit. For 5 and 6 pin devices, I connect the middle pin via copper enamelled wire, shown in red on the picture.
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