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Two Questions
#1

Hi All;
I have two questions, one pretty basic, but I need to confirm my thinking..
First, I have the Old style of Tubes, 4 and 6 pin, so when consulting a tube manual and it show the pin placement.. Is That looking down from the top, going Clockwise from pin 1 (usually Filament) arround till it gets to the other usually filament pin.. And When looking from the bottom is the Counting Counter-Clockwise starting from pin 1 ??
Secondly, I have the Old style Philco IF Cans which have a single hole for both primary and secondary adjustment of the Mica Trimmer Caps.. A screw and a nut adjustment.. Does the Trimmer Cap Go Bad and How can I tell If it has gone Bad ?? And what size is the Trimmer Cap ??
THANK YOU Marty
#2

1. Tubes' pinouts are usually given looking from the pins' side,not from the top of the tube. And they are clockwise. The same pinout will reverse if you look from the top of the tube.
Which is convenient: when you work on chassis, you look at the pins, and so the pinout is exactly what you are given in a diagram.

2. Not that I have an experience even remotely comparable to some folks here (meaning old radio restoration) but for what it's worth, I have yet to see a bad trimmer cap.
#3

Hi All;
Morzh, Thank You for your Answer..
Which I am still a little confused about and here's why.. On my Breadboard set up I have had the Tube wired up as per Your Answer, and I got the funny lower voltage across the Dropping resistor, about 50 Volts (If I remember correctly).. When I temporially shorted the resistor with a jumper clip wire, One of the Grids started to "GLOW RED" and I quickly removed the jumper..
After wiring all pins just the opposite (side to side) The Dropping resistor showed about 120 to 125 Volts just like it was suppossed to.. And after some tweaking as explained in my Oscillator posting, I got the Oscillator to work.. So looking from the Top of the Tube Down starting at pin 1 (left side) which is a filament pin.. I have plate (P), Grid 1 (G1), Grid 2 (G2) and Grids 3 and 5 (G3,5) and pin 6 final filament pin..
Am I reading your Answer correctly or If this is backwards "Why" does it work this way and not wired the other way ??
THANK YOU Marty
#4

Hi All;
I have ordered two 1C6 tubes just in case, they should be in this next week.. I also have ordered the tubes for my Precision E-200 RF Generator just in case..
THANK YOU Marty
#5

Marty

Here goes.

Go to radiomuseum, for example, and see the tube, say, 6J5G. This is one of the tubes i have on 37-116.
http://www.radiomuseum.org/tubes/tube_6j5g.html

Now the way they list the pins on the picture is from the key CLOCKWISE Mass(GND)-F(filament)-A(Anode for Plate)-Empty-Grid-Empty-Filament-K(cathode).

Now let's go to my 116 diagram which lists the tubes' voltages with the pics of the sockets with pins' names.
The note says "Socket Voltages Measured from Underside of Chassis).
This means the pins are lookled at FROM THE BOTTOM.

Now the 6J5G pins go CLOCKWISE (from the bottom):
(unmarked) - F - Plate - (empty) - Grid - (empty) - F - K(cathode).

Now as you can see the pins listed (on the Radio Museum Site) are looked at FROM THE BOTTOM and they are CLOCKWISE.

Same pinout is given here

http://www.r-type.org/pdfs/6j5-2.pdf

PS. Again, I do not know for all tubes whether the convention applies.
#6

Yes, the convention applies to all tubes. The diagram shows the bottom view of the pins, and the pins are numbered clockwise with pin 1 at the lower left.

http://www.classiccmp.org/rtellason/tubedata/1C6.pdf

When you are working on the breadboard, you are looking down from the top and everything is reversed. Pin #1 is at the lower right and the remaining pins are numbered counterclockwise.

Working on breadboards with tubes always drove me crazy just for this reason since you were always used to the chassis bottom view. Then of course came integrated circuits whose pins are diagrammed and labelled from the top view. Growing up with tubes, this required quite a bit of relearning and adjustment!
#7

Hi All;
Thank You, Mondial, And what I have is wired just the opposite of what you are stating.. I agree that looking down from the top of the tube it should be the Mirror immage of the picture in the RCA Tube book that I have, and come Monday morning, baring any other obligations, I will switch the wires back, and try it on all three tubes that I have and see If any of them will work and what my voltages are on each of the pins..
This is one of the reasons "why" I am so very much frustrated, is that it almost works, but not completely works.. And so in the back of my mind I am wondering IF it is because I have some or all or part of it wired Wrong.. I would not think I could get the Oscillator to work and the Dropping Resistor to put the correct voltage on Grid 2 (pin 4) of the 1C6 If I had it wired wrong.. I am not saying that I have it wired correctly I am trying to explain "WHY" I am confused..
So I will try all three Tubes that I have, taking down voltages on all of the Pins and recording them on paper.. Then I will reverse the wires back to what I had them wired at first, the correct way according to what I think is correct and what You (Mondail) are conveying to me and record the voltages on each pin and with each tube.. And see IF we can figure out why this circuit is acting this way..
THANK YOU Mondail for putting up with me and my ranblings and all my back and forth postings.. I hope after I post my findings it becomes perfectly clear what the correct wiring should be.. Or why it has been such a hassle for me.. I really Hope that after I re-wire the tubes it would work just like it is suppossed to work.. And that I had something I didn't see wired wrong and that was why it would not work and led me down this wild goose chase !!
THANK YOU Marty
#8

I'm a little confused (a normal state of affairs for me).

I now see you are using a 1C6 (somehow I had in my mind a 1LC6... go figure). Looking up this tube, I am seeing pins 1 and 6 as filament. From there it goes Pin 2 = Plate, Pin 3 = G2 (osc. plate), Pin 4 = G1 (osc. grid), Pin 5 = G3 & G5, Top cap = G4 (signal grid). This is from pin 1 (the first large pin) clockwise.
#9

View is from the bottom of the tube (pin end).


Attached Files Image(s)
   
#10

Hi All;
Thank You Brenda Ann for coming into this confusing state of affairs.. No, the Tube has always been a 1C6, and looking at your pin out I do see a mistake I had made i had pins 3 and 4 switched in order, I origionally had pin 3 as the Osc grid and pin 4 as the osc plate.. And that may have been my origional problem all along..
So, Monday I will re-wire the tube and wire it correctly for pins 3 and 4, along with the rest of the pins and take some voltage readings and let everyone know what I find..
Hopefully this solves the origional problem, THANK YOU Brenda Ann..
This might explain why I had the grid, not sure which one glowed RED HOT when I shorted the dropping resistor when this origionally started, and which in turn made me think I had it wired backward, and so when I rewired it the dropping resistor showed nornal readings and the Osc worked, I don't know why.. I thought it was my mis-reading of what everyone was telling me.. And possibly all along I had pins 3 and 4 switched..
And THANK YOU Mondail for trying to set me straight, I appreciate your efforts..
THANK YOU Marty




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