fixmeplease
03-03-2016, 11:20 AM
RCA 21-T-8478 U (21T8478) Super Model. Photofact Set 386, folder 4, Jan 1958. Black and white TV
I picked up this Tv a couple months ago. The CRT tested ok except for the life test but I decided to give it a whirl as I really like how it blends into my corner with the angles of my paneling. Im surprised these corner tv's never caught on. As you can see the exterior is in pretty nice shape. Theres one knob a little broken up but I can live with that. No scratches on the glass front which means I never owned it, lol. The large back panel is in great shape but its missing the smaller one where the speaker is. There is a matching flip up lid on the top for controls.
Because of it being fairly difficult to work on and not wanting to damage the yoke taking it in and out (or resoldering it on countless times) I went ahead and replaced all the electro's, paper caps, bumblebees, and a fair amount of resistors, maybe 45-50 parts in all. I detached the yoke so it wouldnt get damaged as i had to flip the chassis over a hundred times. I could get at about half of the board parts from the back side and did those correctly, then did the crush method on the rest, which was a PITA. 5 tubes tested bad and I got replacements.
For some strange reason, it worked when I put it together! :) The CRT isnt real clear but its watchable and the sound is real nice. Good enough to watch news on, or other things like that. CRT is a 21DFP4 originally, but has an Emerald replacement. From my reading these were not very good CRT's.
I want to replace the seleniums which is one of my questions as I have never done it. It has 2, both .280A, RCA #104483. The replacement parts listed include Sarkes Tarzian #M500 which is silicon and are still available online at reasonable prices. Am I better off to use that part or to use a modern diode? And if modern, which number? Do I need to add another resistor? This is a hot set and in the pic of the rectifiers you can see the resistor above it is in poor looking shape. I'm still new to this stuff so it may be hard for me to understand real tech talk so I may have more questions.
My 2nd question involves the yoke. Can I add a plastic connector to the wires so that I dont have to remove it to remove the chassis? Or is that a bad idea? It solders to the chassis right now. The housing was in poor shape and I can still get it mounted and working with a part I made of styrene, but am sure I will damage it with repeated removal. The chassis removal isnt too bad except for the yoke.
Thanks in advance, and I will likely have more questions.
I picked up this Tv a couple months ago. The CRT tested ok except for the life test but I decided to give it a whirl as I really like how it blends into my corner with the angles of my paneling. Im surprised these corner tv's never caught on. As you can see the exterior is in pretty nice shape. Theres one knob a little broken up but I can live with that. No scratches on the glass front which means I never owned it, lol. The large back panel is in great shape but its missing the smaller one where the speaker is. There is a matching flip up lid on the top for controls.
Because of it being fairly difficult to work on and not wanting to damage the yoke taking it in and out (or resoldering it on countless times) I went ahead and replaced all the electro's, paper caps, bumblebees, and a fair amount of resistors, maybe 45-50 parts in all. I detached the yoke so it wouldnt get damaged as i had to flip the chassis over a hundred times. I could get at about half of the board parts from the back side and did those correctly, then did the crush method on the rest, which was a PITA. 5 tubes tested bad and I got replacements.
For some strange reason, it worked when I put it together! :) The CRT isnt real clear but its watchable and the sound is real nice. Good enough to watch news on, or other things like that. CRT is a 21DFP4 originally, but has an Emerald replacement. From my reading these were not very good CRT's.
I want to replace the seleniums which is one of my questions as I have never done it. It has 2, both .280A, RCA #104483. The replacement parts listed include Sarkes Tarzian #M500 which is silicon and are still available online at reasonable prices. Am I better off to use that part or to use a modern diode? And if modern, which number? Do I need to add another resistor? This is a hot set and in the pic of the rectifiers you can see the resistor above it is in poor looking shape. I'm still new to this stuff so it may be hard for me to understand real tech talk so I may have more questions.
My 2nd question involves the yoke. Can I add a plastic connector to the wires so that I dont have to remove it to remove the chassis? Or is that a bad idea? It solders to the chassis right now. The housing was in poor shape and I can still get it mounted and working with a part I made of styrene, but am sure I will damage it with repeated removal. The chassis removal isnt too bad except for the yoke.
Thanks in advance, and I will likely have more questions.