01-24-2022, 04:19 PM
It looks like part #12, an RF choke connected across a 10k resistor to the plate of the 1232 tube. The other end would be connected to another resistor and a 100pf cap.
40-195 Restoration
01-24-2022, 04:19 PM
It looks like part #12, an RF choke connected across a 10k resistor to the plate of the 1232 tube. The other end would be connected to another resistor and a 100pf cap.
01-24-2022, 07:07 PM
Makes sense, thank you Rod.
01-29-2022, 09:57 AM
Question, what does it mean "use loop on generator" in the instructions attached?
Also, which one of these instructions should I use for a 40-195? Thanks in advance!
01-29-2022, 10:24 AM
Create a loop antenna transmitter with a coil of about 5-6 turns of wire 4-6 inches in diameter and connect the hot side of your signal generator to one end. You now have a radio transmitter that varies the radio reception signal strength by how close it is to the receiver.
The second set of instructions can be used for the 40-195 alignment (note upper right corner).
01-29-2022, 11:04 AM
I see, thank you for the clarification Rod as this is a new procedure for me.
One question is does it also need a ground on the signal generator?
01-29-2022, 12:27 PM
Normally no. The loop is small enough to be a short and usually reduces the signal output. But you can always try an earth ground on the other end of the loop just to note the effect.
01-29-2022, 05:47 PM
Rod,
Connecting the loop to the output and tuning the signal generator to the same wavelength as the radio, say 580khz, I should hear a tone from the SG on the radio? If not, what am I doing wrong?
01-29-2022, 06:27 PM
Where are you in the alignment procedure? Make sure the band switch is on broadcast.
01-31-2022, 03:33 PM
Operation 1 was successful connecting to terminal 1 on the back of the radio using a .1mfd inline and the ground to the chassis.
Operation 2 is iffy where the signal does not seem to be very strong if at all. Operation 3 seems to work. Now to qualify something, under Connecting Aligning Instruments, I am not removing the tubes and replacing with an aligning adapter. I am not sure what it even is. I found this document for aligning Philco's which seemed easier to follow but still not much luck.
01-31-2022, 03:36 PM
I should mention that I am using an Eico 330 signal generator that seems to be in working order.
01-31-2022, 04:37 PM
I'm not sure what the aligning adapter is but I can guess. I would say it gives you the capability to use a test meter of lower ohms-per-volt to measure the AVC voltage. Meters of the day would "load" a circuit and indicate a false reading. Using a high impedance DMM or VTVM will have very little impact on the AVC voltage providing it is connected to the high side of the volume control.
02-02-2022, 06:57 PM
I am looking for some guidance with how to go through and validate voltages on the tube pins. I thought I saw someone post something with the tubes and pinnings but I am not positive.
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