Welcome Guest! Be sure you know and follow the Phorum Rules before posting. Thank you and Enjoy! (January 12, 2025) x

Thread Closed

Tuning Eye Help
#16

That's the AGC action. Without an antenna, the AGC isn't in play, since all stations are weak. The radio runs in its 'full open' mode, to allow in the most signal. So, you don't see much, if any, action from the eye tube. Once you connect an antenna, the AGC starts working because of the stronger signal input. As it 'turns on', the AGC goes more negative and applies a DC voltage to the grids of one or more tubes, making them less sensitive to incoming signals. This negative DC voltage then causes your eye tube to begin to close.
#17

Thanks Brenda!.. It's always good to learn new things about radios. I ended up disconnecting R22 and now the eye tube works exactly as needed. The set is almost finished now and I am very happy with it.

The artist formerly known as Puhpow! 8)
#18

I have had the same type of problems with the tuning eye on
various radios and if is a bright green and does not move , I wait until I align the radio and then if it still does not close properly, I start with the troubleshooting.
Glad you got it going..
#19

Another thing to remember is the lower case "m" was also used to designate kilohms, just like the lower case "w" was used to designate Ohms.

That has fouled up many a schematic reader...

73DG

Pacing the cage...
#20

Thanks for that info. It doesn't take much to foul me up..

The artist formerly known as Puhpow! 8)
#21

One more possibility... Unless it's too late. Inside the tube socket cover there is usually a resistor. They OPEN UP, and the tuning eye just sits there. I don't remember the pin numbers, but it's there. It cost less than running another wire up from the chassis. I seem to remeber that the resistor sent amplified AGC voltage to the deflection plate in the tube.




Users browsing this thread: 3 Guest(s)
[-]
Recent Posts
HiFi (Chifi) tube amp build - but my own design.
It's the other forum. I'm also in DIY, but mostly read there. Honestly, I kinda jumped into this without much thought to...TV MAN — 10:43 AM
Philco 71 Code 125
Hello,  I am in need of a schematic for this radio. Mine has the three separate circular tube shields and a shadow me...dconant — 08:06 AM
Stromberg Carlson 1500 Squeal
And life just keeps getting more complicated.dconant — 07:57 AM
54C Complete Teardown/Rebuild
Hello Roy, here is this one sincerely Richardradiorich — 12:45 AM
54C Complete Teardown/Rebuild
Richard, Had grabbed it already but thank you just the same.  I find myself wanting to find some way to block out the...glyphmon — 12:03 AM
54C Complete Teardown/Rebuild
Hello roy, here is a link to the schematic . Sincerely Richardradiorich — 11:54 PM
54C Complete Teardown/Rebuild
Richard, The Silvertone 2014 also is a transformerless set, so I am incorporating a 1:1 600 ohm audio isolation transfo...glyphmon — 11:37 PM
Preliminary work on wife's Silvertone 2014
Did an alignment today which was interesting.  IF alignment went great, almost all was already spot-on.  Adjusting on th...glyphmon — 11:35 PM
54C Complete Teardown/Rebuild
The main problem with adding a Bluetooth input is that this set lacks a traditional power transformer to isolate it from...radiorich — 11:19 PM
54C Cabinet Refinish
I started stripping this cabinet before it got super chilly out because I knew I wasn't going to be able to work on ...glyphmon — 11:18 PM

[-]
Who's Online
There are currently no members online.

>