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Radiotronman 12-27-2015 07:50 PM

1 Attachment(s)
These three chassis should keep me busy awhile. It looks like the vertical section on the if/rf chassis has had some repairs before. Several bumblebee replacements and one electrolytic can has a lot of leakage underneath it too. The if/rf chassis has a few 1000v caps I'll have to order too.

Radiotronman 12-29-2015 05:07 PM

This set has an oddball value wax cap in the vertical section. It's a .06 at 1600v. Can I put a .05 and .01 in a series and be alright? They're both 1600v.

tom.j.fla 12-29-2015 05:26 PM

Hi, Not in series, but across each other. You want the value to add not divide. All the best, Tom

Radiotronman 12-29-2015 05:39 PM

Ok so in parallel, got it thanks!

Electronic M 12-29-2015 05:39 PM

Quote:

Originally Posted by tom.j.fla (Post 3152637)
Hi, Not in series, but across each other. You want the value to add not divide. All the best, Tom

To be more precise in parallel is the way you want to connect the two caps, NOT in series.

Capacitors in parallel add. Capacitors in series take on a value less than the smallest one in the string.....It is the other way around for resistors in series, but the formulas are the same IIRC.

Radiotronman 01-08-2016 08:12 AM

1 Attachment(s)
After replacing 22 electrolytics and all paper caps, excluding 1000v ones, I am getting close to a first power up on a variac! Just waiting on the 1000v caps to come in the mail any day now....I also replaced any out of tolerance resistors and any ones that looked questionable.

ChrisW6ATV 01-08-2016 04:24 PM

Looking good.

Radiotronman 01-10-2016 12:03 PM

Well first power up was a disappointment, with nothing happening. Not a single tube lit up. Back to the drawing board...

Radiotronman 01-11-2016 10:03 PM

Anyone got any ideas? The fuse in the power supply chassis is good and I've checked multiple times to make sure I've hooked all of the cables back up correctly. I'm going to do a continuity check on the on/off switch to make its not defective. I haven't seen a simple switch like that go open before, but I can't imagine why nothing is lighting up?

MIPS 01-11-2016 11:02 PM

Start as close as you can to the AC plug and work your way back until you find where the voltage drops off?
If you aren't even getting the tubes lighting it's going to be something early on. :scratch2:

bandersen 01-11-2016 11:25 PM

I've encountered problems with switches before. After many years of sitting around the contacts can oxidize. Sometimes working the switch a bunch of times can clean them up.

Electronic M 01-12-2016 01:59 AM

Check the resistance between the blades of the plug. It should be less than 200 ohms. If it ain't the switch start ohming the line wiring out.

Eric H 01-12-2016 08:34 AM

There's a lid switch on these too if I recall correctly, make sure it's connected.

Radiotronman 01-12-2016 08:58 AM

Eric,

There's a lid switch? I didn't know that, I will look up under that cabinet and see if I can find it.

Radiotronman 01-12-2016 07:40 PM

Eric was right on with the lid switch! I didn't even see it and from the inside of the cabinet it looked like another control switch. Mine was stuck and after freeing, it powered up. Every tube but the CRT filaments lit up. Now to figure that out. At least I'm moving forward!!


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