Is This Really a 470nF 400V ceramic capacitor ?

[SevMamba]

Hi, I am trying to build an Octopus Curve Tracer from this circuit diagram (see attached file). I'm usually ok building stuff when I have a circuit diagram, but not good at all in designing circuits. I chose this design as it looks fairly simple and has a defined set of components, BUT the parts lists calls for the capacitor C1 to be a 470 nF, 400V, ceramic capacitor. I have been unable to purchase one. The symbol on the diagram shows a polarised capacitor but my research says ceramic capacitors are non-polarised. Looking for a 470nF 400V capacitor brings up a CCB type. My question is, Is This Really a 470nF 400V ceramic capacitor ? or should it be something else.
Thanks, Sev

 

[Alec_t]

Welcome to maker.pro!
Both C1 and R2 have the wrong values if they're driven by the 12V secondary of the transformer and the LED is intended as a 'power on' indicator.

 

[73's de Edd]

Sir Sev Mamba . . . . .

I tracked this circuit down to both a You Tube presentation and a foreign language write up under Scrib -d.
The circuit is the same.

The YELLOW ENCOMPASSED components are there merely for creating a pilot light
Change to the other circuit . . .below it

ADDITIONALLY . . . . .

Since you have the complete article . . . . . . .I'm still looking for GREEN boxed R11 resistor ? ? ?
PLUS . . . ." IMPROVED" . . . . . .Frankly, I can't see any difference from the 1960's circuit and using an OS-8 un triggered /free running Oscilloscope. .

73's de Edd . . . . .

 

[SevMamba]

Sir Sev Mamba . . . . .

I tracked this circuit down to both a You Tube presentation and a foreign language write up under Scrib -d.
The circuit is the same.

The YELLOW ENCOMPASSED components are there merely for creating a pilot light
Change to the other circuit . . .below it
View attachment 65050
ADDITIONALLY . . . . .

Since you have the complete article . . . . . . .I'm still looking for GREEN boxed R11 resistor ? ? ?
PLUS . . . ." IMPROVED" . . . . . .Frankly, I can't see any difference from the 1960's circuit and using an OS-8 un triggered /free running Oscilloscope. .

73's de Edd . . . . .
View attachment 65051

Thank you for your response, when looking for R11 did you mean where is it used or where can you buy a 50ohm resistor? It seems as if the article and circuit diagram are not as good as I first thought. Should I make it and hope for the best or forget it a try another one. I'm tempted to try it and use a 47ohm resistor for R11 as I cannot tell if the original writer meant 500ohn and left off a zero or didn't look up available parts when he/she calculated for a 50 ohm, or indeed really wanted a 5 ohm but typed a zero. What would you do? (No liability with an answer) Thanks

 

[73's de Edd]

I just couldn't find either R10 or R11 on my schematic.
Since the schematic I found, did not show that additional (level calibration) circuitry that you now came back with.
Use two paralleled 100 ohm resistors, as a 50 as they are READILY found.
Your suggestion of his possibly meaning 500 as a value doesn't jive, since the 1x impedance matching RF load of a scope input is 50 ohms.
Just found the WHOLE article . . . . . . . . .

http://www.arrl.org/files/file/QEX_Next_Issue/May-June2017/Ferreora.pdf

Seems. his NEW IMPROVED aspect, was just the progressively switch selected three levels of 60/50!~ AC reference injection .

 

[SevMamba]

I just couldn't find either R10 or R11 on my schematic.
Since the schematic I found, did not show that additional (level calibration) circuitry that you now came back with.
Use two paralleled 100 ohm resistors, as a 50 as they are READILY found.
Your suggestion of his possibly meaning 500 as a value doesn't jive, since the 1x impedance matching RF load of a scope input is 50 ohms.
Just found the WHOLE article . . . . . . . . .

http://www.arrl.org/files/file/QEX_Next_Issue/May-June2017/Ferreora.pdf

Seems. his NEW IMPROVED aspect, was just the progressively switch selected three levels of 60/50!~ AC reference injection .

Thank you again, I'll sort out the parts and give it a try.