Panasonic TR-5041P B/W 5" Portable - help

[demy1942]

Well, I decided to ground down the silver coaxial connector so it can fit in the back. Great picture now, thanks for helping.

[demy1942]

Picture

[demy1942]

Guess what, I broke off the brightness knob off the back after I didn't seat the case correctly, now I can't see the picture. Oh man this sucks

[demy1942]

I really messed up on this one, I am so disappointed, wow had my favorite tv all set and I put the case back on and the knobs in the back, I forgot that they had to stick through the case. I disconnected case and I wiggled them a little bit and the one knob for brightness came off and I can't get it back on. These are the two pieces. I took an alligator clip and clamped the clip onto the board where the knob goes. It does then brighten the screen to make it viewable. Oh man I don't know what to do, so mad about this, killing me.


Suggestions?
Alternatives to this knob attachment. I do have a local tv repair guy but this thing I have no way to keep it attached. Oh man this is a big bummer, going to cry:tear s:

[demy1942]

Okay this is what I did, attached a bolt to squeeze the two pieces together but now no brightness adjustemnt

[JohnCT]

Originally Posted by demy1942

Okay this is what I did, attached a bolt to squeeze the two pieces together but now no brightness adjustemnt

Do you mean the brightness is now fixed at one point or there is no brightness?

If it's the former, you can probably fit a plastic washer (like for metal TO-220 transistors) and tighten the bolt/nut just enough to provide enough contact pressure but still allow adjustment.

If there's no picture, you might have cracked the wafer.

What's the value? I might have one somewhere.

John

[demy1942]

Thanks John, I placed the bolt in there, tightened and now the picture is perfect. However, no adjustment for the brightness. I still have the turning knob for the back but not sure if I can ever attach again.

[zeno]

You can replace it with a trimmer pot of the same size & ohms.
Only thing is it will be a screw driver adjustment at that point but
it will work. These pots are delicate so dont blame yourself too much.
Lesson learned. Believe me over 40 years I broke a ton of things
from a 50 cent knob to a $300 CRT & got paid well to do it !

73 Zeno
LFOD !

[demy1942]

Do you know how I might get one of those? Trimmer pot, ohms?

Thanks

[JohnCT]

Originally Posted by demy1942

Do you know how I might get one of those? Trimmer pot, ohms?

Thanks

What's the value? I have some kicking around.

EDIT: The value is printed on the metal wiper. If it says (for instance), 102 it's a 2K. If it says 153 it's 150K, etc. The last digit being the multiplier. A 1 in the third place means multiply by 10, 2 in the third space means multiply by a hundred, a 3 means multiply by 1000 etc.

John

[zeno]

Brite control VR63 is a 500K ohms. OEM part ## is
EVLVOU15KB55 you never know you may find one.
If you can get a few from the same MFG you may be able to move the shaft over. Main thing is the ohms & a good physical fit, you can mouse it
to fit if need be.

73 Zeno
LFOD !

[demy1942]

Thanks guys for the assistance. I am not too sure about this stuff since I am a noob on fixing the tv's. However, it looks like fun and could I go to an electronic store for stuff?

[Electronic M]

Originally Posted by demy1942

Thanks guys for the assistance. I am not too sure about this stuff since I am a noob on fixing the tv's. However, it looks like fun and could I go to an electronic store for stuff?

Very few electronics stores carry potentiometers anymore. Radio Shack was probably the last big chain that sold that kind of stuff. There are some local surplus and old TV parts houses out there but it depends on where you are at...

Online is more likely to help. If the physical size of the pot is still common you might be able to source a new one from mouser or digikey... though figuring out how to correctly filter results to the best match with any reasonable efficiency is an art that could land you a purchasing job in industry, or qualify you as an engineering intern.

Any pot the same resistance and equal or higher wattage will electrically function...the closer the replacement is mechanically the more it will look and feel right to use.

Ultimately that is around a $1 part in a affordable obtainable 70s portable...If I broke one in one of my sets I'd shrug and see what I could pull out of my junk boxes.... some of us here my self included have 50s color sets where 1-10 examples are known to exist and another set of you can even find one costs a over a grand maybe even 10K....when you work on those putting a scratch or chip you can fix on something can ruin your day.

BTW: just saw your PM... my box is full so I can't send any PMs. Glad I've been able to help. I've been out of commission with the flu since Saturday night...

[JohnCT]

Originally Posted by demy1942

Thanks guys for the assistance. I am not too sure about this stuff since I am a noob on fixing the tv's. However, it looks like fun and could I go to an electronic store for stuff?

Give me a few days. There's a good chance I have one; just have to locate it...



John

[demy1942]

Thanks guys, I hope you feel better, crazy flu going around.