.001 ceramic

[bullpeters]

Hi.I need a .001 uf CERAMIC capacitor for a train wreck clone. I can buy ONE for .34c but the freight is $15!!! I don't really want to argue the very arguable need for this particular part. Its a Trainwreck clone and for once i want to try it right. Any thoughts on salvaging one or perhaps a good sort would drop one in the mail for karma,or at the least some paypal?
Bit desperate
Mick

 

[AndrewT]

Look for 1000p or 102 markings on old capacitors. The flat pancake style usually about 2mm to 6mm diameter and <1mm thick.

 

[indianajo]

old TV's, CRT monitors, and PC power supplies are full of old parts. Walk around early in the morning on garbage pickup day.
The ceramic caps are not usually what failed. I cut them up occasionally for resistors capacitors and diodes. The electrolytic caps are trash.

 

[Enzo]

You will most always run into the basic shipping charge if you order something from a supplier. One cap or a thousand is still a small package that must be shipped, doesn't cost them less for being almost empty.

How about walking into a local electronic repair shop - televisions, stereos, computers, even appliances, and ask them if they have a part they would sell you. If you walked in here, I;d probably just give you one. My sales tickets cost me 15 cents each. SO rather than use up a ticket, i ive the occasional resistor or cap away for free.

 

[geraldfryjr]

You would think that they could stuff one in an envelope and mail it to you !!!!?

jer 🙂

 

[gingertube]

Mick,

Farnell now called Element14, R.S. Electronics for mail order within Oz.

Should be a local Altronics distributor nearby which will have them.
Altronics - Your One Stop Audio Visual & Electronics Supplier

I built a trainwreck, disc ceramic is the go for that cap.
If you get desperate PM me and I'll put a couple in the post from Adelaide.

If you are a member you can see my schematics etc. here - the "Junkbox Trainwreck" built from an old Ozzie AWV PA Amplifier.
http://ampgarage.com/forum/viewtopic.php?t=17851

Cheers,
Ian

 

[bullpeters]

Thanks Ian. I will let u know. Glad for the confirmation about the cap. Thought that the ceramic might just be trainwreck nonsense. I am using 6sn7 triodes for the output, (Idea from AX84.com) Fully regulated power suppy, the bias, the heaters, everything. Powder coated the chassis. Something nice to keep.

 

[gingertube]

The "Junkbox Trainwreck" I did. For your possible interest.

Note you end up with a spare 1/2 of a 12AX7, I added a "wrinkle" of my own by using a parallel input to take advantage of that spare triode. The 2 triodes at dissimilar operating points for a bit of harmonic emphasis.

Cheers,
Ian

 

[bullpeters]

wish you hadnt shown me that. I am just connecting the last bits and i dont want to change anything now. I expect to get about 2watts flat out. I cant imagine 35 watts in my house!!
really nicely drawn schematic.Impressive

 

[Nigel Goodwin]

Thanks Ian. I will let u know. Glad for the confirmation about the cap. Thought that the ceramic might just be trainwreck nonsense.

It is nonsense - no specific need for a ceramic capacitor, any 1000pF of high enough voltage will be absolutely fine.

 

[gingertube]

Nigel may well be right.
I copied this schematic before adding my own "wrinkles".
http://www.blueguitar.org/new/schem/trainwreck/wreckxpr.pdf

It says 0.001 Ceramic parallel with 0.001 poly for that coupling cap so thats what I used.
Probably would not be able to tell the difference if you just used a single 0.0022 (2n2) poly cap.
Poly means, polyester, polypropylene, polystyrene etc. all of which may (or may not) sound a little different. I used polypropylene.

Ceramic Caps suffer from dielectric absorbtion, that is they cause distortion of their own so it is not beyond belief that it does affect the sound somewhat. You will (should) never see a ceramic coupling cap in a HiFi Amp.

Cheers,
Ian

 

[Nigel Goodwin]

Nigel may well be right.
I copied this schematic before adding my own "wrinkles".
http://www.blueguitar.org/new/schem/trainwreck/wreckxpr.pdf

Is the output transformer labelled incorrectly?. 16 ohm in the middle, and 8 ohm at the end?.

It says 0.001 Ceramic parallel with 0.001 poly for that coupling cap so thats what I used.
Probably would not be able to tell the difference if you just used a single 0.0022 (2n2) poly cap.
Poly means, polyester, polypropylene, polystyrene etc. all of which may (or may not) sound a little different. I used polypropylene.

Of course not - it's just a coupling capacitor in a low quality valve amp, neither the type of capacitor or it's value are in any way critical. Personally I probably wouldn't have even considered one that low a value, and probably used 0.01uF throughout.

Ceramic Caps suffer from dielectric absorption, that is they cause distortion of their own so it is not beyond belief that it does affect the sound somewhat. You will (should) never see a ceramic coupling cap in a HiFi Amp.

There's a lot of rubbish written about different types of capacitors causing distortion - but many of the worlds best sounding amplifiers used the supposed 'problem' capacitors and they weren't of any concern.

And it's certainly no concern for a guitar amp 😀

 

[gingertube]

Nigel,
Yes the Output Tranny taps in that linked schematic are wrong. I only copied the preamp part.
Cheers,
Ian