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38-8 mystery thing
#1

hope you can help on Tube 6F6 pin 4 their is a CAP i thank it is not on my schematic, It has a white body at one end is a org ring and at the other side of chassis by 6J5 is a yellow body and a white ring they are 2 watt in size no lettering this is proving to be very interesting with a little German in it
i have found resistors called 99k mmf or 51k mf in the schematic what does the mmf stand for
thanks
john
#2

Better let the little German out! Is it a cap or a resistor? No cap on or needed at the screen grid of the 6F6.
Terry

When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got!

Terry
#3

jstaf40 Wrote:i have found resistors called 99k mmf or 51k mf in the schematic what does the mmf stand for
mmF stands for micro-microfarad. The modern name is picofarad (pF). This is a measure of capacitance, not resistance.

--
Ron Ramirez
Ferdinand IN
#4

thanks Ron i knew about the mmf mf but what is strange is in the # 280 service bulletin on
the replacement parts list # 16,20,32,36 all are called resistors with mf & mmf after the value some thing new to me.....

And can any one tell me the value of the the resistor on my first message it's on the 6F6 PIN 4 it not on the schematic..... has a WHITE body with a ORANGE RING at one end & in front of the 6j5 on a 3 pin terminal it has a YELLOW body with a WHITE RING at one end the size looks like a 2watt i need to replace them but do not know the value hope some one can help
#5

Okay, I just looked at Bulletin 280...boy, did someone at Philco screw up on that one...everywhere you see resistors in the parts list with "mmf" or "mf," substitute the word ohms.

Are you saying a white body with orange paint on one end, or orange on one side, close to - but not on - an end of the resistor? The schematic does not show any resistor on the screen grid of the 6F6G. What does the other end of this resistor connect to?

As for the other resistor (yellow body with white ring?), it could be yellow body - white end - yellow dot (not seen because of the yellow body), which would be 490,000 ohms (490K). There is a 490K resistor in the vicinity of the 6J5G, resistor (21), which is 1/2 watt. One end connects to the junction of resistor (20) and capacitors (19D) and (24); the other end connects to ground.

--
Ron Ramirez
Ferdinand IN
#6

Ron
the yellow with white BAND i get a reading of .531 meg ohms and goes one end to ground to #24 cap to the vol cont.

the white with org BAND is 1/8" from the edge goes to 6f7 pin 4 to 6k5 pin 3 i read 114 k both of the resistors our about 1/4" and a light brown insides the only 2 like that, And i notice some other resistors the ohms were right on to the schematic,, but the color code was switched around not like today's must be philco code before today's standard
thank for your help
john




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