[Boatanchors] Ceramic disk caps

[Bob Hardie- W5UQ]

Guys, there are different caps for different applications. For example, 
a 1000 pfd cap in a circuit at 1 MHz is made differently to a cap in a 
60 MHz circuit and  the one in the UHF range is different yet ....plus 
the one in the microwave freqs is different yet. Take a resistor... at 
the HF freqs, it can be a regular resistor... at UHF and MW freqs, the 
resistor may need to be spread out on a ceramic plate so that the "skin 
effect" of the resistor is different to the plain ole one for HF.    
Caps are different toooooooooo.

One has to consider how the circuit was designed and what is best.  One 
can "break the rules" and of course, it just may work.  BUT it may not 
work the next time.
SO--Glen is right...  pay attention to what he says if you want to have 
"less problems" when you rebuild a radio.  Learn the rules.

Follow the rules and you will be a better boy....  Sometimes when a cap 
is bad and  I don't have the right one, I sub the wrong type just to see 
if it works better... BUT I ALWAYS put the right type in when I get it.
Do it right or IT WILL HAUNT YOU LATER.... Ahhhhhh  haaaaaaaaa haaaaaaaa 
(echoing in a chamber)......
Now...   Hey Gene, do you like to get the boys stirred up some... you 
getting bored up thar in Spring Hill?
Bob

Glen Zook wrote:
> It does matter!  You are still dealing with r.f.
>
> In the audio circuits for coupling (i.e. the 12AX7 and 6DE7) use orange drops or similar where the paper type capacitors were before.  You can use disc ceramics for the bypass capacitors in the audio circuits as well.
>
> Besides being better for r.f. disc ceramic capacitors are MUCH cheaper than orange drops, etc.
>
> Glen, K9STH
>
> Website:  http://k9sth.com
>
>
> --- On Tue, 3/3/09, WØQFC <erastber at tampabay.rr.com> wrote:
>
> My question about the disc caps came up because I am rebuilding several DX-35 and DX-40 rigs.
>  
> I understand that discs are better for bypassing in RF circuits because of their lower inductance, but in a circuits like the DX-35/40 does it really make THAT much difference?
>
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