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  #1  
Old 09-04-2011, 11:11 PM
Red Raster's Avatar
Red Raster Red Raster is offline
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Join Date: Aug 2010
Location: Prince George B.C. Canada
Posts: 184
Out of the Doghouse

On the last post i just received a box of capacitors and started to restuff the eletrolytics and all the wax paper caps that were restuffable.


The 80uf / 450 VDC were the easiest to restuff.


One of the 80 uf capacitors reinstalled.


Done! all recapped, Some of the capacitors were not suitable canidates for restuffing,
A look of old and new.


At this stage of the restoration was the moment of truth, what
reward will i get when i power up the set? The good news is no smoke
and i have inteligent sound but no raster. Having proper B+ voltages
for the deflection circuits and a text book perfect saw tooth waveform
on the grid of the horizontal output, Hmm the horiz out tube is
suspiciously cold and is definitely not conducting. An open 100 ohm
5 watt current limiting resistor in the cathode circuit will certainly
cause this condition. (blue ceramic resistor that is open)
Now i have sound, a good raster, but no picture and no smoke!.

Well it turns out that the video if stage was starving no B+, The 6AG5s
may be small but they need to be fed. Quick trouble shooting led me
to two open resistors, a 2.5k and 6.8 k part of R 213 a three section
resistor combination. Added are two modern 10 ceramic resistors.

Here is where things really come together, a stable image that was
very easy to setup with the adjustment controls on the rear of the chasis.
As mentioned by some VK members this set is a solid performer when restored and to add that, my expirence with this set is it warms up
quickly and needs no further adjustment. Now for the scary part the Tektronics 2246 is 22 years old and at least has found re employment.


Overal this set has turned out pretty good. I would like to replace
the two multi section resistors with originals and on the cosmetic side
of things one of the wooden knobs is in rough shape and the clear
plastic tuning dial disc is split. A big round of thanks to all the VK members for
your support and input given on this fun and yet to be continued thread.
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  #2  
Old 09-05-2011, 12:49 AM
Phil Nelson's Avatar
Phil Nelson Phil Nelson is offline
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Join Date: Jan 2006
Posts: 4,030
Nice work. You're right about the set-and-forget nature of this TV. My RA-103 is the most stable vintage set in the house. DuMonts are fun to work on, too. Very well built.

Phil Nelson
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  #3  
Old 09-05-2011, 01:46 AM
DaveWM DaveWM is offline
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Join Date: Feb 2009
Location: Orlando FL
Posts: 5,607
Nice, love the string tied wires, Nice work on the stuffing of the caps. Overall a very handsome looking set.
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  #4  
Old 09-05-2011, 08:36 AM
vts1134's Avatar
vts1134 vts1134 is offline
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Join Date: Apr 2011
Location: Pittsburgh, PA
Posts: 1,534
Fantastic Work! The set looks great. This set is one my potential next projects. I hope mine goes as well as yours.
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