Sony KV-2643R score

[freakaftr8]

Absolutely agree. Most of the vintage color sets I've picked up showed weak sleepy emission. the 8v overnight trick brought most back to life into the green.

As to Electronic M, yes I always thought that any heater without cathode use causes oxidation. I just dont understand why Sony would make a big deal of econoquick if the SS circuitry was a 8 to 10 second wait from dead cold anyway.

A far leap from a non instant on full vacuum tube tv that took 30 or more seconds to produce picture, in which yes, instant on reduced CRT life and vaccum tube life as well.

[zeno]

A few notes on all of this.
Econoquick is just a fast warm up CRT. No STBY voltage.

Almost all SS sets WITHOUT a power transformer use a flyback (FBT) winding
for the CRT filament. Some sets ground on end & others "float" it at apx 130V.
This is to keep the F & cathode close DC wise to reduce arking & H-K shorting.

Service notes.
Always look for cold joints especially if the set has a PCB for the CRT socket.
Early RCA in line CRT sets used a spring contact socket. Many had toasting & went intermintant ( RCA, Admiral, Maggy, Sears/Warwick ). The plastic key on the CRT would melt & the contacts burn. Repair was a new socket, remove key, clean & bend F pins out slightly then put the key back on.

Sets with H-K short & grounded F.
There was a rash of Sanyo built Sears with Sylvania jugs that shorted H-K.
This coinsided with mass failures of the Z0064 HV rect, divider that kept us quite busy ! They used a grounded F configuration. Repair was to isolate the
F from ground ( cut etch & run a wire). Place a 1.5 meg resistor between
the shorting K & f. Also add IIRC a .01 cap from the K to ground. This made the set usable again but you could still see when it shorted in the pix.
$50 sure beat a new set for the customer !

Low E. Caution some risk !!!
You should use a scope for this ! Measure the P-P filament first. You want to
increase the F about 20-25%. Most sets have a low value resistor in series
with the F ( apx 2 ohm 1 W ). Jump it out & watch the scope for the change in P-P.
Early sets had an "open" FBT with the core for the pulse winding exposed.
Try adding a turn to the F winding. Use the scope to watch the P-P. Again not
a perfect solution but sure beats a new CRT !

Instant on.
One of my biggest beefs. Instant on is a killer especially on all tube TV's from
all MFG's. All of us are quick to condemn it. BUT on SS sets its a different
story IMHO. Ask anyone here what CRT holds up best from the 70's. 90%
will answer Zenith chromacolor jugs. The flat chassis & E line CC2 sets both
had instant on............

I am tired, nuf sed fer now
73 Zeno
LFOD !

[freakaftr8]

Well I found a 220k ohm resistor on the H2. There is an H1 and H2. Obviously I cant read with a DVM. Could you elaborate on this low value resistor jumping?

Essentially increasing heater voltage it sounds.

I still have a focus issue on the outside perimeter of the CRT I cannot achieve with dialing focus around. also blue and red smearing from weak R and B emission although it retains good brightness and contrast even with the smearing with my chassis derived rejuvenation. lol

I know it's most likely a weak crt, just surprised it can retain a really bright raster with quite a bit of contrast, not like the usual Trinitron weak crt.

But it does exhibit the smearing as contrast level goes up. And quite a bit out of focus around the perimeter.

[zeno]

Wrong resistor. It should be just a few ohms. If not on CRT PCB trace the F
wires back to the FBT. It also may not be there at all.

Originally Posted by freakaftr8

Well I found a 220k ohm resistor on the H2. There is an H1 and H2. Obviously I cant read with a DVM. Could you elaborate on this low value resistor jumping?

Essentially increasing heater voltage it sounds.

I still have a focus issue on the outside perimeter of the CRT I cannot achieve with dialing focus around. also blue and red smearing from weak R and B emission although it retains good brightness and contrast even with the smearing with my chassis derived rejuvenation. lol

I know it's most likely a weak crt, just surprised it can retain a really bright raster with quite a bit of contrast, not like the usual Trinitron weak crt.

But it does exhibit the smearing as contrast level goes up. And quite a bit out of focus around the perimeter.