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Interesting problem with Philco 38-62
#1

Ever since I've owned this radio, (almost a year), it has had come-and-go problems with the RF amp circuit. It needs a really strong antenna to work passably well. What normally works on all my other radios, you have to multiply it by five for it to work on this radio. It stopped working last night, and I immediately turned my attention to the 6A8G. I put my finger on top of the grid cap and the wire that goes to the tuning condensor and it immediately starts blaring my 1410 KHz AM transmitter tunes. I pulled the schematic, and I'm going to see if changing the tube and replacing the wax capacitors in the RF amp circuit help.

Side note, this radio has the broadcast band and 2.3 to 2.5 MC band. I'd like to make use of the band switch, since 2.3 to 2.5 is dead now. I want to turn it into a tone switch, but I bet it isn't as simple as unsoldering the wires and sticking in a capacitor that goes to the audio output across the switch.  


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Slave to an RCA Victor CTC-25
#2

Have you check the antenna transformer integrity yet? #2?

People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
#3

Yup, I agree. If substituting your body for the antenna coil results in a good signal being produced from the 6A8G, then I would suggest that there is insufficient signal getting thru' the antenna transformer into the 6A8G
#4

Oh boy. That looks like a joy to troubleshoot.

Slave to an RCA Victor CTC-25
#5

This is not bad at all.

In the coil #2 measure between pins 1-2 (25 Ohm) and 3-4-5 (2.5 ohm from the center to either end). If it checks out and the soldering / wiring is good, then we move elsewhere.

People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
#6

Okay, I can probably handle that. But not until March 12th when I get to go back to the Radio Club.

Slave to an RCA Victor CTC-25
#7

You don't have a meter at home?

People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
#8

I have a Voltohmyst, but it has issues.

Slave to an RCA Victor CTC-25
#9

As long as it can reliably show short from open, it is enough.

People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.




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