electroking
09-20-2008, 08:24 PM
Hello,
This past week, I began working on my 1956 Viking (Eaton's store
brand, built by Electrohome) 21-inch set. I acquired it from an elderly
lady who claimed that the set had been retired to a corner of her
dining room in 1964, after her family bought a newer set. According
to her, the set had been working fine at the time.
So I removed the rear cover, and saw a lot of dust in a uniform thick layer
over every horizontal surface, no traces of burning or anything the like.
I removed the CRT socket, noting that the base on the tube was still
solidly glued in place. I tested the tube with a Heathkit tester, and
the needle was pegged to the max, as should be for a new tube according
to the manual. Cutoff checked OK as well.
After I put the CRT socket back in place, I studied my schematic, began
looking for electrolytic and other capacitors, and also proceeded to do
some professional work.
Earlier this evening, I felt an urge to do a smoke test, in spite of all the
warnings I have read here and elsewhere, especially in the case of a
set that has not been turned on in 44 years. With the rear cover still
off, I plugged the set, turned it on, and observed both sides. I had
rabbit ears installed, and a strong local channel tuned.
Fortunately, there were no clicks, pops or flames. I got clear sound with
no hum, but no picture at all. I just rotated the contrast and brightness
knobs, to no avail. The set was on for no more than 90 seconds I would
say. I checked that the CRT cathode was lit.
I suspect that there is no high voltage, and I am now afraid it could be
a dead flyback trans. Of course I don't intend to do any more live testing
until I have pulled the chassis and inspected underneath. Any ideas?
Also, this appears to be a 'one-piece' assembly, meaning that the CRT
is attached to the chassis rather than to the cabinet. Any advice on
pulling this? Thanks in advance.
P.S.: I thought it showed on the attached figure, but the CRT type
is 21ALP4A.
This past week, I began working on my 1956 Viking (Eaton's store
brand, built by Electrohome) 21-inch set. I acquired it from an elderly
lady who claimed that the set had been retired to a corner of her
dining room in 1964, after her family bought a newer set. According
to her, the set had been working fine at the time.
So I removed the rear cover, and saw a lot of dust in a uniform thick layer
over every horizontal surface, no traces of burning or anything the like.
I removed the CRT socket, noting that the base on the tube was still
solidly glued in place. I tested the tube with a Heathkit tester, and
the needle was pegged to the max, as should be for a new tube according
to the manual. Cutoff checked OK as well.
After I put the CRT socket back in place, I studied my schematic, began
looking for electrolytic and other capacitors, and also proceeded to do
some professional work.
Earlier this evening, I felt an urge to do a smoke test, in spite of all the
warnings I have read here and elsewhere, especially in the case of a
set that has not been turned on in 44 years. With the rear cover still
off, I plugged the set, turned it on, and observed both sides. I had
rabbit ears installed, and a strong local channel tuned.
Fortunately, there were no clicks, pops or flames. I got clear sound with
no hum, but no picture at all. I just rotated the contrast and brightness
knobs, to no avail. The set was on for no more than 90 seconds I would
say. I checked that the CRT cathode was lit.
I suspect that there is no high voltage, and I am now afraid it could be
a dead flyback trans. Of course I don't intend to do any more live testing
until I have pulled the chassis and inspected underneath. Any ideas?
Also, this appears to be a 'one-piece' assembly, meaning that the CRT
is attached to the chassis rather than to the cabinet. Any advice on
pulling this? Thanks in advance.
P.S.: I thought it showed on the attached figure, but the CRT type
is 21ALP4A.