Sony KV-2643R score

[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 !