|
|
|
#1
06-01-2015, 07:41 AM
|
||||
|
||||
|
Zenith Porthole flyback question.
Hey guys, quick video explaining my questions if I need to install this replacement fly in my Zenith. Thanks for any feedback you may have.
http://youtu.be/j4WkVgW6W1E
__________________
-Al 
|
|
#2
06-01-2015, 03:55 PM
|
||||
|
||||
|
I would connect 7 as it was originally wired and not use 1.
|
|
#3
06-01-2015, 11:06 PM
|
||||
|
||||
|
Bob, did you mean connect the replacememt fly as the original one? That would mean ignoring the new tap 7 on replacement fly and keeping the damper tube and horizontal deflection coils connected to the no. 1 tap as original.
__________________
-Al
|
|
#4
06-01-2015, 11:08 PM
|
||||
|
||||
|
Or did you mean NOT use tap 1 on replacement fly and connect both damper and horiz. deflection coils both to new tap no. 7? Could you explain a bit if this is the case. Thx.
__________________
-Al
|
|
#5
06-02-2015, 08:08 AM
|
||||
|
||||
|
I checked schematics for the 1947-53 Zenith (Wallace Telaide) and did not see terminal 7 on the flys for chassis using 6W4/25W4.
The fly for J-chassis (6AX4 damper)is similar but has the additional tap, as shown on the Merit replacement diagram. K and later chassis have a different fly. Only the later G-line chassis show the tapped-winding width coil. Those show damper cathode and yoke on terminal one also. Yours is a single winding width coil.
__________________
"When resistors increase in value, they're worthless" -Dave G
|
| Audiokarma |
|
#6
06-02-2015, 10:19 AM
|
||||
|
||||
|
I suppose using 1 does make more sense after watching the video again. If that doesn't give you sufficient width and boost voltage, try tap 7.
|
|
#7
06-02-2015, 11:51 AM
|
||||
|
||||
|
Hey thanks for these posts guys. If my original fly tests bad (waiting on Eico 944 tester), I will install the replacement and keep the wiring the same as the original, ignoring new tap 7.
Windings 2-3 and 4-5 of the original fly are ohm'ing out way higher than they should be. More than double on both. THX!!!
__________________
-Al
|
|
#8
06-03-2015, 07:13 PM
|
||||
|
||||
|
Received my Eico 944 tester today. Works great! Replacememt flyback tests awesome. Original tests bad. Needle dropped out of the green to the very top of the red. Which seems to correspond to the barely visible dim raster I was getting. Time to replace my first flyback!!!!
__________________
-Al
|
|
#9
06-04-2015, 12:20 AM
|
||||
|
||||
|
Proceeded to test the yoke next. BAD! Vertical is buried in the red and horizontal is in space between green and red ranges. So will replace yoke too.
I used the tester on a known good yoke that I had as well, just to be sure. Tests that one fine - GOOD.
__________________
-Al
|
|
#10
06-05-2015, 12:48 AM
|
||||
|
||||
|
__________________
-Al
|
| Audiokarma |
|
#11
06-05-2015, 12:07 PM
|
||||
|
||||
|
If there is an AGC control try adjusting it. Also look at video anp tubes, their base voltages, and if it uses a SS video detector don't rule out it being weak or bad.
How does your HV compare to the schematic? A bad/marginal yoke could drag down the HV. It is normal for hold to be disturbed by height/linearity adjustments. The collapse to line is likely a bad spot in the pot you were turning...You might want to try cleaning it.
__________________
Tom C. Zenith: The quality stays in EVEN after the name falls off! What I want. --> http://www.videokarma.org/showpost.p...62&postcount=4
|
 |
|
|
Linear Mode
