what's this symbol in the fairchild 670 diagram?

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Wow!! Nice pic!

Sorry for delay in replying, at the Southampton boat show...

So, I'm not sure what the groupDIY upload thing is?

Is there a link? Or am I being dumb? (few drinks in the sun!)

best
pete
 
Bloody Hell CJ, do you have a time machine? That looks like it was only just made. Our one is slightly more "grubby" inside.....
 
6386 tube data sheet
it has all the load lines included:


http://vacuumbrain.com/The_Lab/Fairchild/670_Pics/6386.pdf

Control Input
UTC 6431

6431_1.jpg




670_3.jpg



8b_1.JPG


Here is a resistor and partial cap list
Accuracy is not verified from my end.

Fairchild 670

Resistors

6.8    ½  watt  10%  1 ea.
30      ½ watt    1%    4 ea.
33      1 watt    10%  2 ea.
150    ½  watt  10%  8 ea.
180    ½  watt  10%  4 ea.
560    ½  watt  10%  4 ea.
560    1 watt    10%  4 ea.
680    ½  watt  10%  8 ea.
1000  1 watt    10%  5 ea.
2700  1 watt    10%  4 ea.
3900  1 watt    10%  2 ea.
4700  ½  watt  10%  2 ea.
10K  ½  watt  10%  1 ea.
27K  ½  watt  10%  1 ea.
27K  1 watt    10%  1 ea.
47K  ½  watt  10%  4 ea.
68K  ½  watt  10%  2 ea.
100K ½  watt  10%  5 ea.
100K 1 watt    10%  8 ea.
100K 2 watt    10%  4 ea.
150K ½  watt  10%  4 ea.
150K 1 watt    10%  1 ea.
220K ½  watt  10%  2 ea.
270K ½  watt  10%  3 ea.
470K ½  watt  10%  3 ea.
1M    ½  watt  10%  6 ea.

93 Total


Capacitors

20 pf    1 KV          4 ea.
0.05uF  400 VDC  4 ea.
0.1uF    200 VDC  2 ea.
0.1uF    400 VDC  4 ea.

2uF      200 VDC  2 ea.
4uF      150 VDC  2 ea.
4uF      440 VAC  1 ea.  (note:  probably oiled filled)
8uF      150VDC    2 ea.
20uF    150VDC    2 ea.
25uF    25VDC      1 ea.
60uF    450VDC    2 ea.
140uF  350VDC    2 ea.
250uF  50VDC      2 ea.
1000uF 15VDC      1 ea.

C109,C209  ???/200VDC  2 ea.  any help here? I think it’s 0.1
Schematics unclear

35 Total 



 
Close up of Logo:

fairchild670logo.jpg


yet another inside shot
fairchild670_10.JPG

fairchild670_6.JPG


fairchild670_2.JPG


nice overall shot...
http://vacuumbrain.com/The_Lab/Fairchild/670_Pics/wireing_a.jpg

fun with the 670 cathode current paths

cathode_670.jpg


another print, harder to read...

550kb!
http://vacuumbrain.com/The_Lab/Fairchild/670_download.jpg

transformer layout

670irona.jpg



660>670 inventor
http://vacuumbrain.com/The_Lab/Fairchild/Rein_Narma/Rein_3.jpg

660>670 inventor with slide rule  sf hyatt

http://vacuumbrain.com/The_Lab/Fairchild/Rein_Narma/Rein_2.jpg



 
no problem,
and the y-6431 data was hiding in the utc folder,

since the 6386 is now available, the only real tough part is this pesky control input.
here is some stuff on that...

UTC Y-6431

Ratio: 1:9.7 or 600:55,300 ohms @ 1000cps , open circuit
ferq response-10db rise @ 40 kcps

pri-2 ea.=43.21 and 43.34 ohms dcr each-1.05  and 1.04 henries each (Gen-Rad)
capacitance 180 pf from pin 1 to any terminal
D=0.383 (B-K Precision Handheld Bridge)

sec-2 ea. 1.667 and 1.692 k ohms dcr -100 henries ea. (Gen-Rad)
D= 0.157 (B-K)

winding data:

Core: UI31  15/32" stack

S1 red>F3 brn -500 turns #38- 4 Layers
S6 blk>F8 grn  - 4800 turns of #43- 21 Layers
S2>F4 - 500t #38 4L
S5>F7  - 4800t #43 - 21L

1 mil insulation



and the triad if interested...


Fairchild 670 Signal Amp Output = Triad HS 52

255 Turns of #31 

1425 Turnsa of #39

1425 Turns #39

255 Turns #31

50/50 Core 21 EI LAms 1/2 x 7/8 inch stack...
 
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