All things LA2a related

[wave]

If I'm supposed to leave the clip where it is and ohm out the diodes on the b turret side I'm getting 2Mohms if I'm not supposed to measure like that then I guess I dont get what you're saying.
Also thanks for helping me I know you must get tired of troubleshooting this stuff
:guinness: :guinness: :guinness:

 

[CJ]

No, I like trouble shooting on the net. It's a nice challenge.

OK, clip your black lead to the minus terminal of one of those filter caps.
I don't think we had a good ground, like Mr. Potatoe head was saying on page 40. Dang, I can't even spell Pototo!

Then re measure the diodes on both sides.

Make sure your red lead is not plugged into the ma socket by mistake. (do it every day at work)

 

[wave]

Clip to filter minus
Diodes on turret A side : no reading (OL)
Diodes on turret B side : I got fluctuating readings ranging from 3Mohms to 500Kohms

 

[Scenaria]

"The first toy product ever advertised on television was Mr. Potato Head. Introduced in 1952, Mr. Potato Head took advantage of TV's explosive growth to gain access to tens of millions of newly "plugged-in" households."

 

[CJ]

OK, you might have done this already, but do it one more time for a reality check.

Tape up the secondary wires from the transformer so they don't short out to the chassis. Don't tape them together!

Then re fuse and plug in the unit. Pull all the tubes first.

We just want to get a win by having nothing blow up, and having the pilot light go on.

 

[wave]

Including the center taps?

 

[CJ]

Yes. We just want to get the primary circuit working so there is something to build on.

 

[wave]

OK sorry it took so long
Tubes in, fuse in, switch on, fuse doesnt blow no pops or smoke

 

[CJ]

Are the tubes lit?
How about a pilot lamp on the front panel, if using one?
Power switch working?

 

[wave]

Nothing is lit (no tubes lit, I'm not using a pilot) but if all the secondaries are taped up how would any voltage get anywhere?
Power switch is working

 

[CJ]

OK, cool.
Lets hook up the heaters. No center tap.
Just two green wires.
Plug just one tube in for starters.

Make it the 6AQ5.

 

[wave]

OK
Heaters hooked up all tubes light up :grin:

 

[CJ]

That's one Heineken.

OK, next, hookup the secondary centertap, but not the red wires.

 

[wave]

Both centertaps?

 

[CJ]

One, then power on and if no smoke, number two.
I know it's a hassle, but .....

 

[wave]

Green one first?
(this is definitely not a hassle I'm just glad youre helping or I'd be screwed) :sam: :sam: :sam: :sam: :thumb:

 

[CJ]

OK, lets go with the green one.

This is brute force troubleshooting here, but were close to finding the smoke bomb.

 

[wave]

OK
Did green first.... no problems
Then red.. NO PROBLEMS!!!!
:sam: :sam: :sam: :sam: :thumb: :thumb:

 

[CJ]

Oh boy. Silence means you found it!
Or your internet provider took a hit.

In case everything is cool so far, ground your center taps and hook a 1 meg resistor (if you have one, 1/4 watt is ok) from one of the red wires to one of the diodes and carefully measure the ac voltage across it.

 

[wave]

I dont have a 1 Meg.
Also I thought the red secondary was 250 VDC how do I get AC across the diode?

...I have a 1 Meg pot though