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The 200 and 201 chassis were only used in the X cabinets. That's what makes it a 201X the combination of a given chassis and a particular style cabinet. For the most part X,H, and L are consoles. B's are cathedrals and tombstones. CS, LZ,LZX, and RX are chairsets. The list goes on...
Math is not my strong suit but here's a starting point. Perhaps one of the Mike's can help out will this issue.
https://www.electronics-notes.com/articl...filter.php For now you could connect the top of the 100K resistor over the plate of the 75 to get it working.
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
(This post was last modified: 05-19-2021, 08:18 PM by
Radioroslyn.)
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bgorman, here is a website that can help you calculate the inductance you need!
https://goodcalculators.com/resonant-fre...alculator/
Ron
Bendix 0626. RCA 8BX5. RCA T64
Philco 41-250. Philco49-500
GE 201. Philco 39-25
Motorola 61X13. Philco 46-42 Crosley 52TQ
Philco 37-116. Philco 70
AK 35 Philco 46-350
Philco 620B. Zenith Transoceanic B-600
Philco 60B. Majestic 50
Philco 52-944. AK 84
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>For now you could connect the top of the 100K resistor over the plate of the 75 to get it working<
Nice, I was thinking that I could do that very thing to at least be able to test it. Learning a little more everyday from you all.
Also thanks for the info on what the different letters mean.
(This post was last modified: 05-22-2021, 09:16 PM by
bgorman.)
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Ron
Thank you so much for the link, major time saver for me.
So in the calculator, for frequency, would I use the 10 KC it supposed to create ??
and the circuit has caps #69 & #72 as well as the #71 (adjustable). would I measure the total capacitance of all 3 ?
If so, the total capacitance measures out at 370 pf
If I plug in those 2 factors
10 Khz
370 pf
It gives me 684 Millihenries Does this seem right?
(This post was last modified: 05-22-2021, 10:23 PM by
bgorman.)
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I believe 69 & 72 are there to remove any residual IF carrier frequency left after demodulation. I would just use whatever value 71 is to solve for the inductance of 70.
Ron
Bendix 0626. RCA 8BX5. RCA T64
Philco 41-250. Philco49-500
GE 201. Philco 39-25
Motorola 61X13. Philco 46-42 Crosley 52TQ
Philco 37-116. Philco 70
AK 35 Philco 46-350
Philco 620B. Zenith Transoceanic B-600
Philco 60B. Majestic 50
Philco 52-944. AK 84
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City: wentzville, mo.
Life got busy here, but back at this unit. Hoping to get this figured out and be able to move on.
So the compensating cap #71 (as it is adjusted) measures 280 pf
The trap is 10KC
If I plug those 2 values into the calculator Ron links too, it gives almost 1H inductance. I'm no expert at this so wondering if that seems right ??
I found a 1H choke at antique electronics P-T158T but its only 40 ohms. If the calculation is correct would this one work ??
Thanks
Bob
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I come up with approx. .9 H. Not being an engineer, I would give it a try with the part you found and see how it goes, it won’t hurt anything! GL.
Ron
Bendix 0626. RCA 8BX5. RCA T64
Philco 41-250. Philco49-500
GE 201. Philco 39-25
Motorola 61X13. Philco 46-42 Crosley 52TQ
Philco 37-116. Philco 70
AK 35 Philco 46-350
Philco 620B. Zenith Transoceanic B-600
Philco 60B. Majestic 50
Philco 52-944. AK 84
Posts: 29
Threads: 2
Joined: Sep 2017
City: wentzville, mo.
< I come up with approx. .9 H. Not being an engineer, I would give it a try with the part you found and see how it goes, it won’t hurt anything! GL. >
Great thank you for chiming in Ron, feel more comfortable with trying it.
Bob