Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5

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: 1 Guest(s)
[-]
Recent Posts
Philco 60 Squealing
All correct shields must be in place, all tubes correct no subs of any kind. Check any soldered, riveted ground conne...Chas — 01:24 PM
Philco 60 Squealing
I have recapped and replaced out of tolerance resistors and so on. Radio plays nicely on fairly strong stations. The pro...dconant — 10:55 AM
Philco 46-420 Code 121 Reception issues
Welcome Eric, I agree with Bob and far as the two main electrolytic filter capacitors did you change them yourself or w...radiorich — 11:43 PM
Philco 46-420 Code 121 Reception issues
You mentioned the Philco manual and going through the check points...just to be sure we're on the same page here's the m...klondike98 — 08:13 PM
Philco 42-1008 conversion kit
Interesting. I haven't seen that before.klondike98 — 07:02 PM
12' Philco
Yes I had looked for it on the web as well some time back and could not find it. I was glad to see it turned up in Ron'...klondike98 — 06:59 PM
Shadow Meter Bulb
Now if you had a set with a tuning light then the bulb type is important to the circuit, some sets used those prior to t...Arran — 04:58 PM
Shadow Meter Bulb
Ok. Thanks for the correction.RossH — 03:09 PM
Model 28L
For 28 you will probably need to buy a Hammond 125CSE. Or any of the series of the power you need, with SE suffix. Then ...morzh — 02:09 PM
37-60 revision 6
I am restoring a Philco 37-60 and it shows run 6 they removed the ground from G3 of the 6K7G and put the G3 to -2.5v for...bobbyd1200 — 01:01 PM

[-]
Who's Online
There are currently 3195 online users. [Complete List]
» 1 Member(s) | 3194 Guest(s)
Avatar

>