November 17, 2010 at 3:34 am #2051TangoForum Participant
Hello. I just thougth I’d introduce myself. I am about to embark on my first radio restoration / rescue.
About 7 or 8 years ago i was given a CGE console radio, model JK-126. 12 tubes, AM and a few shortwave bands, and I think 8 pushbutton stations. My brother had it out in Victoria and it worked there, but now it just hums, although the leads to the beam-scope (?) antenna are cut. I took a look at the power cord and saw bare copper where it disappears into the chassis and decided maybe it needed some TLC before we go any further.
At that time i got a set of replacement caps from justradios.com and for a simple reason the project stalled. (My wife hates the radio, thinks art-deco is incompatible with our home). I think its gorgeous, but who wants to rebuild a radio that has to hid in the basement?
Well, now the kids are out of the house and theoretically i have more time and maybe a spare room that I can claim, so I want to work on it this winter. The cabinet also needs refinishing including a veneer repair that a kindly nearby radio fixer convinced me I can handle. I’ve refinished lots of furniture, but not veneer and not on curved surfaces.
The first thing I am doing is disassembling it by removing the chassis, make sure that there are no surprises, and dissassemble the woodwork to the max extent. Replace the power cord. The tuner drive belt(s) look to challenge a rubiks cube for complexity, but that is a last step after the chassis is back home some months from now. Then I’ll do the caps that should be done. 28 of them. Then maybe crank it up with a dim-bulb gizmo and see whats what.
I’ve read a lot of articles on line and videos on youtube and have never seen so much conflicting information in my life. Cut the old leads and solder to them / remove the old leads entirely to make sure that you get a good connection / leave the old leads in place because dont fix what aint broke / recap the radio first thing (just the electrolytics and paper thingies) / and the last book said "get the radio working THEN recap as necessary". Huh?
Anyway, I look forward to discussing with you all as I go.
TimNovember 17, 2010 at 4:10 pm #2056TangoForum Participant
I have a technical background, but in mechanical engineering and technology, definitely not electronics and as of now I have no test equipment other than an analogue multi meter, forceps and a soldering iron. I will make a dimbulb tester, it looks pretty straightforward.
So, this is new ground for me. Once I get the chassis out and try to actually compare reality with the wiring diagram I will get a pretty good idea if I feel comfortable proceeding. If not, I will seek some advice, but I am open to unsolicited advice at all times, feel free.
I was going to add a fuse, but thanks for reminding me, also on the location suggestion, and yes I expect to completely remove any trace of that scary power cord. The radio nameplate says "170 Watts" IIRC so I was going to put in a 2A fuse to start.
I read somewhere that the resistors have to be disconnected before you can test them, which discouraged me. I havent taken the time yet to read the circuit diagram to see if that seems to make sense or not.
Thanks for the tips.
TDecember 24, 2010 at 11:22 pm #2141cvrsForum Participant
”I read somewhere that the resistors have to be disconnected before you can test them”
you can always put your meter leads across a resistor ( not powered on) and check the reading. Sure there is a possibility that there could be another way for something else to be a secondary route between the two ends of the resistor. If there were ( for example another resistor in parallel) then the meter would read low, less resistance.
As Gerry noted the resistors might drift up in value over time, you can check to see if that is the case There can be nothing else in the circuit, such as another route, that connects the two test points across the resistor that could possibly raise the resistance value, another route can only lower the resistance..
So yes you can do some preliminary checking without unsoldering anything, Then if in doubt unsolder one leg to make sure nothing else is interfering.
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