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At least in my admittedly (very) limited experience, the Most Repairman-Unfriendly and Remarkably Unsafe TV to Work On Award goes to the 1958 RCA 17" B&W portable I got about 10 years ago. It's pretty cool looking-- a fine example of a TV-that's-trying-to-look-like-a-car-that's-trying-to-look-like-a-jet-plane. ...Complete with two-tone blue paint job and decorative (gold-colored) "fins" on the side. Heaven help you if it needs repair though.
It's been a while, so I may have some of the details wrong, but here's what I recall. Also, I didn't have any service docs for this set, so perhaps there's a "secret" dissasembly method that I wasn't aware of.
Like many late-50's sets, it has a steel cabinet with a vertical chassis, with the tube sockets facing the back of the set. Some components are on a PC board, but it's mounted sideways with the tube sockets facing the side of the set. The limited clearance between the PC board and the side of the cabinet is made all the worse because the speaker is also mounted to the cabinet there. There's just enough room to stick a hand in there to change tubes on the PC board, but that's it. Oh, and the foil side of the board is covered with a metal shield. Did I mention that the PC board is of the typical 50's variety where a lot of the foil traces have long-ago peeled from the board itself, and now scarcely millimeters away from touching that metal shield..?
If you need to do (almost) anything besides changing a tube, then the real fun begins. As I recall, removing the chassis involves the following steps (and a lot of patience):
- Remove all the knobs (of course).
- On the inside of the set, remove the self-tapping machine screws that hold the chassis to the brackets welded to the metal cabinet. Avoid cutting yourself on the sharp edges of the cabinet lip or the metal brackets.
- No, you can't remove the chassis yet.
- Unbolt the speaker from the cabinet. Set it aside.
- You're definitely not done yet.
- Disconnect the CRT socket. Loosen the yoke and partially slide it off the CRT. Don't worry about the yoke slipping off the neck. It's not going anywhere. The yoke leads are so short the yoke will hardly move anyway.
No, there is no detachable plug/socket for the yoke.
- On second thought, tighten the yoke again. There's something else you have to do first. Remove the external screws that hold the front bezel (including the safety glass) in place. Pull off the front bezel.
- This will reveal several screws that hold the CRT in place (on a metal band/bracket, as I recall). It will also reveal the sharp edges of the front of the metal cabinet. Loosen the yoke again, and then start removing those screws. Keep your other hand at the back of the set-- don't let the CRT fall!
- Done removing the CRT mounting screws? Great! Now, work the CRT forward so as to remove it from the cabinet, while continuing to support the neck of the tube.
- Now discover that the 2nd anode (HV) cable has so little slack that you can only move the CRT about an inch or two forward. Oh, there's the HV cable; it was hidden behind the chassis where you couldn't see it. Another thing you couldn't see is that the HV cable is completely lacking the usual 'suction cup'-- or any other insulation-- at the 2nd anode terminal. So you better make darn sure that CRT is completely discharged and stays that way!
- Now you get to snake your hand into the slim space between the edge of the cabinet front and the bell of the CRT and blindly grope for the HV lead and disconnect it, all while trying not to cut yourself on the unprotected edge of the sheet metal cabinet or getting *zapped* by the unprotected HV lead.
- Having accomplished that, finish removing the CRT from the cabinet from the front. Don't relax yet, though-- you've got to keep one hand in back at the base of the CRT ready to "catch" the yoke before it falls off the CRT neck and smashes into a tube or something.
- Set the CRT aside. Now you can remove the chassis. Well, it's not quite *that* simple. It's a pretty tight fit, and you have to manuver it out the back of the cabinet over, under, and through those mounting brackets as well as the bent lip of the cabinet back.
- Now on your work table you have the chassis! ...along with a CRT, the front bezel, the speaker, and an empty cabinet. Marvel at how thin and flimsy that cabinet really is when it no longer has any internal support-- I've seen tin cans that had heavier steel than that cabinet.
- Repeat the above steps in reverse to re-install the chassis. Have fun!
I'd say it's easier to pull the chassis in the RCA 630TS (and its friends) even though that also involves removing the CRT first...
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