Hey guys.
The John broskie Octal CCDA kit arrived a couple of days ago and while l build most of it i do have a few questions..
disclaimer: I am a complete novice and a language barrier does exist here - please please please be patient with me.
the manual can be downloaded here:
http://tubecad.com/Product_PDFs/CCDA%20Octal.pdf
R18 has two slots alowing two resistor to sit in sequence - but i only recived one.. should i just place and bridge were the other should be? not sure what to do here.. after double checking this it seems the unknown resistor is actually R17 - which dosnt make too much sense (to me..). it says in the manual the R17 and R16 set the voltage to the heaters - but they are on the B+ suuply...
also, just above C7 (if you look at the picture of the board in the last page) there is a slot for a resistr and it is unmarked.. is it a test point or do i need to place a resistor there?
on page 9 there is an explantion about R9 (two resistors in parallel - R9a and R9b) and how to choose their correct value. im not sure how to go about it.. from what it says, i can either choose a shorter tube life and better sound or the other way around.. what values should i place there in order to go with the first option (better sound..). im using 6sn7.
on page 7 you can read about the how to connect the cathode resistor. i am totally confused by this. im not even sure at this point which resistor RK is or which value i use. also, im not sure if i need to go with the conventional of Positive feedback option.. the manual got me completely confused on this part (should i use a bypass cap or not, what is the bypass cap, which values.. etc..)
and finaly..
ok, is it just me or s there a substantial difference between the schematics and the PCB as far as the tube connections go?!
here is the pcb:
[IMGDEAD]https://lh5.googleusercontent.com/-0DDFlVLEQKU/UWiR-Cb8fhI/AAAAAAAABmk/j319szNTvSg/s512/IMG_20130413_015812.jpg[/IMGDEAD]
for example, R4 connects to leg 2 on the board but according the schematics it is supposed to connect to leg 1 and 6. same with R5 - connect with leg 4 on the board but leg 7 on the schematics.
what am i missing here
(i just hope im not asing too many questions at once
)
here are some pictures from the build for you guys to inspect:
https://picasaweb.google.com/111109714414066634160/OctalCCDAProject?authuser=0&feat=directlink
thank you so much for your time and help.
tank out.
The John broskie Octal CCDA kit arrived a couple of days ago and while l build most of it i do have a few questions..
disclaimer: I am a complete novice and a language barrier does exist here - please please please be patient with me.
the manual can be downloaded here:
http://tubecad.com/Product_PDFs/CCDA%20Octal.pdf
R18 has two slots alowing two resistor to sit in sequence - but i only recived one.. should i just place and bridge were the other should be? not sure what to do here.. after double checking this it seems the unknown resistor is actually R17 - which dosnt make too much sense (to me..). it says in the manual the R17 and R16 set the voltage to the heaters - but they are on the B+ suuply...
also, just above C7 (if you look at the picture of the board in the last page) there is a slot for a resistr and it is unmarked.. is it a test point or do i need to place a resistor there?
on page 9 there is an explantion about R9 (two resistors in parallel - R9a and R9b) and how to choose their correct value. im not sure how to go about it.. from what it says, i can either choose a shorter tube life and better sound or the other way around.. what values should i place there in order to go with the first option (better sound..). im using 6sn7.
on page 7 you can read about the how to connect the cathode resistor. i am totally confused by this. im not even sure at this point which resistor RK is or which value i use. also, im not sure if i need to go with the conventional of Positive feedback option.. the manual got me completely confused on this part (should i use a bypass cap or not, what is the bypass cap, which values.. etc..)
and finaly..
ok, is it just me or s there a substantial difference between the schematics and the PCB as far as the tube connections go?!
here is the pcb:
[IMGDEAD]https://lh5.googleusercontent.com/-0DDFlVLEQKU/UWiR-Cb8fhI/AAAAAAAABmk/j319szNTvSg/s512/IMG_20130413_015812.jpg[/IMGDEAD]
for example, R4 connects to leg 2 on the board but according the schematics it is supposed to connect to leg 1 and 6. same with R5 - connect with leg 4 on the board but leg 7 on the schematics.
what am i missing here

(i just hope im not asing too many questions at once
here are some pictures from the build for you guys to inspect:
https://picasaweb.google.com/111109714414066634160/OctalCCDAProject?authuser=0&feat=directlink
thank you so much for your time and help.
tank out.
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